OLD-Mikl's Articles

Planting a tree puts us in touch with one of the most essential parts of a tree that is often overlooked—the roots. When a seed germinates, the first part to develop is the root. The seed has stored nutrients, but if the plant is to live, it must immediately make a relationship with the nourishment of the earth. Then it can make the sprout that pushes into the sunlight to start photosynthesizing. So the first matter of importance in planting a tree is to honor its roots—their condition, their future environment and their nourishment.

But before we dig a hole, we should take into account another matter of importance, namely the elements of size and time, so the right location and choice of tree are essential to tree planting. First determine if you want a shade tree or an ornamental or fruit tree. A shade tree will dominate the landscape. It will cool the house in the summer and provide a shady refuge outdoors. It will also cost more to be pruned and will limit the sun-loving plants that will grow near it. If you do want to plant a shade tree, plant it on the south side or the west side of the house for the greatest value. The late afternoon sun in Colorado is very intense coming through the west windows late in the day. Remember: most rock garden plants, many shrubs and flowering perennials, natives and xeriscape plants need at least 6 hours of direct sun.

An ornamental tree is one that is usually 15’-30’ tall and wide and that flopwers or has ornamental fruits, fall color, attractive leaves or bark. These should also be sited for best effect. They often branch lower than a shade tree and so can provide screening. But if 8’-10’ is enough to provide a screen, it might be better to plant a big shrub. If the tree is evergreen, be careful not to plant it where it will block our valuable winter sun to the  house or where it will shade a sidewalk or entry that will be icy in the winter. Don’t plant a tree under a power line or too close to the house or the sidewalk. Look around the neighborhood to see successful spacings of trees to structures.

Now that we know where to dig the hole, let’s consider how to dig the hole. For this article, I am assuming that we are planting a tree that is in a container. Most balled and burlap trees are too heavy for a homeowner, and I will mention B&B later.

The hole should be the same depth as it is in the pot and a minimum of twice the diameter of the pot and three times the diameter is better. A tree in a 5 gallon pot will require approximately a12” deep hole, a 7 or 10 gallon tree, a few inches deeper. Most tree roots live in the top 8”-12” with some bracing roots going deeper. That is because tree roots need oxygen and the nourishment that is more available in the top of the soil. When digging the hole, I take the top 6” and put it on one side of the hole and put the lower 6” on the other side. Some people like to slope the side of the hole and maybe that is helpful.

Next we must determine what to add to the soil in which we will be planting our tree. It has become popular lately to instruct us to not use amendments, but to plant in the soil just as it is. It is claimed that if we put compost in the backfill that the tree will grow confined and confused as if in a pot or that amendments are not needed. And if I were planting a tree in Iowa soil, I might agree, but I always plant with 1/3 compost and 2/3 original soil. Certainly if we use more than 50% compost we could have problems. And if we plant in unamended soil, most trees will still grow. But these are my reasons for amending: Almost all Colorado soils are low in organic matter and nitrogen. Compost holds water to help get a tree established when it has few roots. Compost opens the structure of the soil allowing rain to penetrate to the roots and allowing air to the roots. It also allows the new hair roots to more easily push through the soil. And compost provides food for the soil life to prosper. These beneficial fungi, bacteria, earthworms etc bring water and nutrients, dissolve minerals and in many ways support the health of the tree.

Besides adding compost we can add microorganisms directly. There is always life in the soil, but we have found by experience that adding some extra at planting, supports a more rapid root development which helps a tree establish faster and to grow more successfully. The first month of a tree’s life after planting is the most critical to its success. We can use a powdered mycorrhizae, wetting the tree roots and dusting on a small amount. We can use a water soluble form and directly apply it to the roots with a watering can, or we can apply a microbe-rich compost tea or even a worm casting tea to the roots before planting. Adding mycorrhizae is most important in new developments where the soil may be trucked-in subsoil with little soil life.

Some trees like pear, apple, crabapple, aspen or birch need ample air to their roots; in poorly drained soils these trees are susceptible to fireblight, fungal diseases or root rot. Especially if the soil is a dense clay or is in a low spot that collects water, it helps to mix 10%-20% Expanded Shale into the backfill. This locally mined shale is fired in a kiln which makes it porous so that it holds both water and air and does not break down over time, like compost does. This makes Expanded Shale a true “clay-buster”. In addition, it may be helpful to add a little organic fertilizer to the backfill. Since our soils are often low in nitrogen, an organic fertilizer that is 3%-8% nitrogen can be helpful. The old warning not to fertilize when planting is only valid for chemical fertilizers that are water soluble and force top growth when the roots need to establish. Organic fertilizers are slow-release, and a half cup to a cup will provide nutrients both for the tree and for the beneficial microorganisms. All these amendments should be added to the top layer of soil taken from your hole.

So now you can take the tree out of the pot. Lift it by the trunk (maybe with a helper) and tap on the edge of the pot all around until the pot falls off. Then set the tree on the ground and tease the roots out of their confined form so they are not circling but are ready to move into the surrounding soil. If the tree has been in the container too long and you can’t pull the roots out of the circling shape, you may have to cut a few roots to open them up. Tip the tree on its side and loosen or cut the roots on the bottom. When a tree grows from a seed, it makes an open root system. So help your new tree with that in mind.

If the ground is dry, put water in the hole before planting, and let it sink in. Then sit your tree in its big hole. The depth is critical. There have been many problems with people planting too deep. This will suffocate the roots and put wet soil against the trunk bark which is not adapted to wet and can rot. This is a common problem with Balled and Burlap trees that are put into containers and “topped-off” with soil. The over-reaction to this is planting too high. This is also a problem because the roots are not designed to be in the sunlight and air, and the tree will dry out out, even if it is drought-resistant. When I interviewed the late, great tree scientist Alex Shigo in 2000 for the Colorado Gardener, he said, “Why not plant a tree at the correct depth? Where the trunk flares should be the ground level.” You can place a board across the hole level with the ground to check where the soil level will be on the trunk. Then if it is too high, dig a little deeper and if it is too low, lift out the tree and add a little soil. If you have to add a lot, tamp the soil so the tree does not settle too deep. Now wet the roots with mycorrhizae.

Then add the amended backfill soil 3”-4” at a time firming a little with your hands, adding water and then some more soil until it is filled to the proper depth. Now take the subsoil on the other side of the hole and make a little berm around the tree, the same diameter as the hole and fill that with water. If you have planted the tree in a lawn, you can place a tree ring 1” thick and 2’-3’ in diameter around the tree. They are made of recycled rubber that lets water through but keeps weeds and grass from growing near the trunk. This is very important to keep mowers and weed trimmers from damaging the young tree trunks. If not in a lawn, the berm-well can be filled with 2” of wood chip mulch. Be sure this mulch is at least 2” from the trunk, because wet mulch can rot the bark.

It can be very helpful to use a tree wrap to prevent sun scald, to prevent rabbits from eating the bark and deer from shredding the bark with their antlers in the velvet stage. The thin bark of a young tree can be damaged by our stronger winter sun, especially if the tree was grown in Oregon. In the old days when a tree was dug, the south side of the trunk was marked and then oriented in the same direction when it was planted. Paper tree wraps can hold moisture against the bark, and are only supposed to be left on through the winter. I like the plastic spiral tree wraps that shade and shield the trunk from animals, but allow air to circulate underneath.

A potted tree rarely needs staking, because the top is not that big and it is better for strong trunk development for it to flex in the wind. If there are broken branches or dead branches or stubs, these can be removed, but a young tree benefits from every leaf that photosynthesizes. If the tree is very tall and whispy, then tip no more than 10% of its height. Otherwise, leave the pruning for a later year.

A company selling Balled and Burlap (B&B) trees has advertised, “Plant a tree, not a stick”, and certainly a new containerized tree can be very small, but it has a developed root system and will begin growing immediately. Many B&B trees are successful, but when they are dug in the field, 50%-90% of their roots are left in the ground, so they are naturally stressed and can take one or two years to start growing.

Alex Shigo instructed us to “Touch Trees”. If we touch our tree to be planted with care and with the knowledge that it can live long and will often benefit others beyond our own lifetime, then we will see that it is well-planted.

Trees do a lot for us humans, so we shouldn’t forget to give them some support. When I look at the treeless ten acre lot next to our nursery, or when I see an old photo of the CU campus with bare land around Old Main, I remember why we can’t take trees for granted in Colorado. Trees really have it hard here, but there are things we can do to help them survive and thrive.

To begin, we must choose tree varieties that like Colorado conditions. The CSU website has a very valuable downloadable resource to help us, the Front Range Tree Recommendation List. 250 trees were evaluated by local experts and the trees are rated A thru D for their success. Just because you see stunning photos or have fond memories of Pin Oaks, Red Maples and Bradford Pears doesn’t mean they will thrive in our alkaline soils, violent temperture swings and the worst fireblight in the country. For example: never plant an apple or pear that is not resistant to fireblight. A Radiant Crab is rated “A”, a Royalty Crab “D” because of fireblight. And our alkaline soils make certain nutrients, like iron, less available, resulting in weakened trees of some varieties.

And it is important where you buy a tree. Trees are not well cared for in Big Box stores and a stressed tree is a poor investment. Some Balled-and Burlap trees come from Oregon or other dissimilar environments. B&B trees do better if they are locally grown. They also do better if they are not too big. People want to start with a big tree, but the bigger the trunk diameter, the more roots that are left in the ground when they are dug. A tree with a 2” trunk diameter will need less water to establish and will be less stressed than a 4” diameter tree, and will start growing faster.

With our average annual rainfall between 12” and 20”, we have to water most trees, and lawn irrigation systems are not designed for trees. Most trees want deeper and less frequent waterings than bluegrass lawns. In fact most trees would be a lot happier outside a lawn. Jack Phillips, principal of New Tree School, has said “Trees did not evolve in landscapes dominated by lawn…Progressive tree care requires a movement away from green sterility and toward a wilderness in soil.”

What Jack means is that not only does grass drink a tree’s water and starve it for oxygen, chemical lawn care starves it for organic matter and kills off the soil life that are a tree’s allies. Trees need less water in spring when we have precipitation and twice the watering in July when it is so hot and dry. Remember: soggy soils have little space for air, and trees need oxygen to their roots as much as they need water.

Because of our dry autumns, sunny winters and winter warm spells it is very helpful to trees to winter-water, especially evergreen trees and trees planted in the current year. Water early on a sunny day to give time for the water to soak in before night-time freezing. Water long enough to penetrate 6”-8”. No need to water if the ground is frozen. A sprinkler works better than a deep-root needle. Remember: Colorado is in a semi-arid region, we are a mile closer to the sun and we lack the winter cloud cover of the regions where many of us grew up, and where most of our trees originated.

Our soils are not the rich glacier deposits of the Midwest. Clay is okay, but it needs more than water to grow strong trees. There are exceptions: native oaks, Russian Hawthorn, Boxelder. But unamended Colorado soils are all deficient in organic matter and nitrogen, from a tree’s point of view. There are those that disagree with me, but I will stand my ground, based on 35 years in the tree care business.

I do not believe in using chemical fertilizers which are made from natural gas, lack micronutrients and are water soluble, pushing fast growth that is soft and susceptible to fungal diseases and sucking insects. I do believe in planting a tree with 30% compost and a little organic fertilizer. And I think periodic feeding with an organic fertilizer and minerals is good, especially if you also are giving the tree some mycorrhizae and mulching over the root zone. I favor this approach because I believe it is necessary to make up for the lack of natural pile-up of leaves and branches that feed the soil on the forest floor. Yes, there are already mycorrhizae in our poor soils, but experience shows that trees establish faster and have fewer disease problems and need less water when humans give them a good mycorrhizae supplement or compost tea. And yes, trees will grow without fertilizer, but not only will they grow faster, but trees with good nutrition will be stronger and more able to cope with Colorado’s harsh environmental conditions. The two best times to fertilize are early spring and early fall and the best time is early fall, because that is when trees are storing nutrients in their roots and stems. This is where the energy will come from if they have to make a new set of leaves after a late spring freeze or to ward off an insect or disease.

According to research done by Ralph Zentz, a Ft. Collins city forester, 70%-90% of all tree problems are abiotic. That means few tree problems are caused by insects and diseases; most are caused by environmental and cultural conditions. This is good news since it means,  we can generally support our trees without spraying anything or having to pay to have something (especially something toxic) sprayed on our trees. So choose a tree that likes Colorado, plant it in the sun or part shade if it prefers, water it deeply and infrequently and once a month in the winter, prune it correctly, and give it organic nutrition so that its soil allies will prosper. Then it will have the vitality to breathe carbon from the atmosphere and build a structure that stands the wind and snow, and provides shade, fruit, beauty and habitat.

According to some reports, Colorado weather in 2014-2015 has resulted in the deaths of 80% of our cherry, plum and peach trees. How did this happen? Does it make sense to replant? And if so, how can we reduce future losses and increase fruitful successes? This article will focus on cherry trees.

The Colorado Front Range is well known for our normally difficult gardening conditions: low day-time humidity, large day-night temperature variations, abrupt weather changes, many mild winter days with occasional extreme cold, some extremely early snows (Sept) and late snows (May/June), occasional major wind storms and common hail storms.

But in 2014, a long, mild fall kept plants green and growing into November when temperatures dropped from the 60s to well below zero in 2-3 days. When plants have not gone dormant, the water in their cells freeze, and the ice crystals rupture the cells, damage tissues and damage or kill fruit buds. If cold is more gradual, a layer of cells forms between the leaf stem and the branch, cutting off sap to the leaf. Then as the green chlorophyll diminishes, the less dominant pigments of yellow, orange, red and brown create the fall colors. Soon after, the leaf falls. If the cold occurs suddenly, the corky layer has not had time to form between the leaf stem and the branch, the leaves flash freeze and eventually fall, leaving openings into the tree through which fungal diseases can enter. This can cause serious die-back of branches and even death. This occurred around 1990 when large numbers of Siberian Elms died and died-back. And it happened again because of the November, 2014 deep freeze.

Boulder County Extension Agent Carol O’Meara, reported that the combination of the November flash freeze, followed by the Mother’s Day snow, followed by a very cool, wet May, caused damage and stresses that favored cytospera canker disease and left many fruit trees dead, damaged or fruitless.

According to the 2014 Climate Change in Colorado report, Colorado temperatures have already warmed by 2 degrees F. over the last 30 years, and could warm 2 ½ to 6 ½ degrees more by 2050. This could lead not only to drier conditions, but also to extended warmer Autumns, which could trick trees into delaying dormancy.

With these weather issues in mind, does it make sense to plant fruit trees like cherries here on the Front Range of Colorado? Of course I’m prejudiced because I have a plant nursery, but I would say, yes! Historically there have been a lot of orchards in Denver, Boulder, Lyons, Loveland and Ft. Collins. The 1935 census showed 516,000 cherry trees growing in Colorado, with one orchard in Loveland being the biggest cherry orchard west of the Mississippi. Drought, late spring freezes, 41degrees below zero in 1951, and a shortage of canning supplies caused by WWII destroyed the pie cherry industry in Colorado. However, as many of us know, tart cherries are often very productive in our area, providing wonderful eating and healthy benefits for us.

So which cherry varieties should we be growing and how should we cultivate them?

First, it is good to discuss cherry rootstock, as most cherry trees are produced by grafting in order to duplicate a named variety. It was found that Prunus mahalab was a better rootstock than Prunus mazzard, because P. mahalab produced faster growth, was more tolerant of alkaline soils and is better adapted to drier conditions. Some wilder forms of tart cherry can be reproduced by suckers, but these form thickets. In the old days some cherry orchards grew trees from seed.

The most common variety of sour cherry (Prunus cerasus) grown for the pie-cherry industry in the 30s and 40s was Montmorency. It is still very popular and usually successful. It is a cross between a sweet cherry and Nanking Cherry (Prunus tomentosa). Montmorency is very productive, very flavorful, highly valued today for its anti-inflammatory qualities, the most popular with birds (they know), and hardy to zone 4. It grows 12’ high by 15’ wide. Many Montmorency trees died or died back in the 2014 deep freeze. However it is still a good tree, and since stone fruit trees are rarely strong and healthy for more than 15 years or so, it is good to replant a new one every 10 years, anyway.

Bali Cherry is my current favorite. It is a Canadian variety, hardy to zone 3, and it did not die last year. The fruit is sweeter than Montmorency, and the tree grows to 12’. North Star Cherry is a natural dwarf to only 6’-8’ and is the easiest to net by tying the netting to the trunk which prevents birds from getting trapped. It is a good tasting tart cherry and is hardy to zone 3 or 4. Meteor is a tart cherry, zone 4, that blooms one week later than Montmorency. Mesabi is a cross between a sweet and a tart cherry. It grows 10’ high and 15’ wide, and is hardy to zone 4. These tart cherries are all self-fertile, so they do not need a pollinator. They are hardier than sweet cherries, have fewer diseases and are more tolerant of hot summers and harsh conditions.

Most Sweet Cherries, Prunus avium, are only hardy to zone 5, bloom earlier and are therefore more vulnerable to late frosts and seldom fruit here. Most sweet cherries on the Front Range died last year. Many new varieties are being bred so there is hope that one may be hardy and successful here.

There is a relatively new Canadian bush type cherry that may be useful here. The most often available are Carmine Jewel and Crimson Passion. They are hardy to zone 2 or 3, have full-sized fruit that is classified as sour, but is said to taste sweet. They grow on a 6’ bush, and are self-fertile but more productive when pollinated by Nanking Cherry.

There is also a selection of Nanking Cherry called ‘Orient’ that has a flavor superior to the species and with fruit that is slightly smaller than a tree cherry.

Cherries do best in well-drained (not wet) sandy loam soils with some organic matter, like compost. They prosper when fertilized in the fall with an organic fertilizer, and watered once a week, especially when the fruits are maturing. They appreciate some pruning but do not remove more than 15-20% yearly. You can lighten clay soils to improve their performance, by adding expanded shale to the planting mix 10-20% by volume.

If you are replanting, it best not to plant in the old cherry location. Stop watering in October to encourage dormancy, then water right before a cold period because moist soil holds heat better and the extra humidity results in the air cooling more slowly. Planting near a building, a big rock or on the north side of a building can moderate temperature swings.

Remember that home-grown fruit is fresher, can be left to ripen on the tree, which makes it sweeter, and often comes in quantities that can be shared or bartered. If a 10-20 year-old fruit tree dies in an extreme weather event, it is likely that if you plant another, it could live as long or longer. But if Climate Change does bring more extremes, pay attention to the varieties that survive and thrive in these extremes. This is the best opportunity to select the new plant variations that have adapted best.

P.S. Regarding our climate, don’t be fooled by references to The Colorado Freeze, which was established in 2014 with the hope of bringing women’s tackle football back to the Denver area.

Parsley is not merely a garnish. Besides its wide-ranging multicultural culinary uses, it has, like many culinary herbs, significant nutritional and medicinal values and important roles in the garden. And in Ancient Greece, parsley was used to crown heroes. Every part of the plant is useful.

Parsley (Petroselinum crispum) is an attractive, very cold-hardy biennial herb in the Apiaceae (bee-flower) family. It is available in flat-leaf and curled-leaf forms, both of which have rich, glossy green serrated leaves on slender stalks. In the first year, parsley continually produces a mass of foliage, which can be freely harvested as needed. Parsley usually survives our winters, and begins to grow fresh foliage the second spring. As the second summer approaches, it stops producing foliage and sends up 2’ flower stalks, which branch indefinitely, holding many flat lacy clusters of tiny yellow flowers, throughout summer. Then it makes seed, and dies. If permitted, it will self-sow and perpetuate your parsley patch forever. If you dig up your plant at the end of the first summer, then you lose the tiny yellow flowers, containing loads of nutritious nectar, that are highly attractive to honeybees, other pollinators (many species of bees and butterflies) and beneficial insects, such as Hover Flies, whose larvae eat aphids and thrips. Like many members of its family, parsley is an essential host plant for swallowtail butterfly caterpillars, so grow enough to feed them, too.

Parsley is also beneficial as a ‘companion’ plant. It is said to increase the fragrance and essential oils of roses growing near it, and to benefit the growth of chives, peppers, tomatoes, carrots and especially asparagus. Avoid planting it near mints and lettuce.

Medicinally, parsley leaves, seeds and root have been used for centuries. It has anti-inflammatory and antioxidant values for relieving stomach problems and rheumatoid arthritis. It is said to inhibit tumor formation, increase circulation and help dissolve kidney stones. Commercial parsley essential oils can be very strong and should be used with caution. Parsley is very high in Vitamin K and rich in vitamins A, C and iron. It is not only nutritious and delicious, but chewing a few fresh leaves is enough to cleanse your breath of garlic or onion odor.

For culinary use, curled-leaf parsley is tasty, but has a milder flavor and stiffer texture than flat-leaf, and is the ever-perky type used to garnish a platter. Varieties include: Triple Curled, Forest Green, Pagoda and Frisca.  But the Italian, flat-leaf type is preferred for cooking and drying. It is commonly used in soups, stews, pesto and curries, and I love it in salads with tomatoes. Varieties include: Giant of Italy, Wild Parsley, Italian Dark Green and Survivor. My wife, Eve, makes one of my favorite summer foods: Quinoa Tabbouleh, with lots of parsley. (see the recipe below). She also sprinkles it fresh over bowls of her Greek Egg-Lemon Soup. Yum!! And a sprinkling of fresh parsley over boiled potatoes, elevates them above bachelor-fare. And parsley pesto is a delicious, vitamin-packed sauce or condiment. Hundreds of years ago, parsley varieties were selected and bred for thick, carrot-like roots, which give parsley flavor to soups, etc., and are known as Hamburg parsley, or Parsley Root. The book ‘Parsley Greats’ offers 100 tasty recipes using parsley.

Parsley is easy to grow in full or part sun in most soils, but it does prefer composted soil, watered once or twice a week. Parsley even does well in containers that can be brought indoors in the winter, where it likes a cool, sunny location and some misting. It over-winters outdoors in the ground and can be mulched with straw or leaves to be harvested through most winters.

The gardener must be patient to plant parsley from seed, as it is slow to germinate. It helps to soak the seed in water overnight just before sowing in early spring, 8-10 weeks before the last frost. It can be sown in the ground, or indoors in pots. Parsley seedlings should be hardened-off and planted out when they are 2” tall.

Parsley is native to the Mediterranean region, and both wild and garden forms were known to the ancient Greeks. Heroes of the Olympic Games were crowned with olive, but for 450 years, winners of other athletic games were crowned with parsley. It was used in cooking in England before the Norman Conquest, and was brought over to America on the Mayflower.

We should all be growing and using more parsley, even if it does get caught in our teeth.

Byline: Mikl and Eve Brawner are co-owners of Harlequin’s Gardens nursery specializing in organic veggie and herb starts, pollinator-friendly, neonic-free plants, hardy roses and xeriscape.

Japanese Beetle is one of the most damaging insect pests in the Eastern and Midwestern US, but until recently, Coloradans were spared that challenge. It entered the US in 1916, but took until 2003 before a population was established in Colorado. This first infestation was in the Palisade area on the Western Slope. Even though eradication efforts were mostly successful there, established populations have been found since 2005 in Pueblo, southern Denver, Englewood, at DU and at Denver Botanic Gardens. Smaller populations are being seen now in Boulder and Jefferson County.

Japanese Beetle is a scarab type beetle about a half inch long, with a metallic green body and copper-colored covers on its wings. In its larval stage, it is a white C-shaped grub, an inch long at maturity. According to our state entomologist, Whitney Cranshaw, adults emerge from soil or turf in late June, July and early August. They only live 4-8 weeks, but can cause significant damage in that time. After mating, the female lays eggs in moist turf, the eggs hatch into grubs that eat the roots of grass. When the numbers of grubs is large, they can kill areas of the lawn. The grubs are mature by September and they burrow down and go dormant over the winter. In spring they feed for 4-6 weeks, then pupate for a few weeks before emerging as beetles.

Japanese Beetle is the most widespread turf-grass pest in the US. The adult beetles eat the foliage and flowers of over 200 species of plants including: grape, crab apple and apple, rose, linden, Norway Maple, birch, cherry, plum, apricot, peach, raspberry, vegetables and some ornamental shrubs. Virginia Creeper and strawberries are particular favorites. Veggies that are eaten are: green beans, okra, corn, asparagus and basil.

Plants that are resistant to Japanese Beetle are: lilac, spruce, chokecherry, elderberry, Bur Oak, Bittersweet Vine, boxwood, forsythia, hydrangea, juniper, mockorange, pear, pine, smokebush, snowberry, Silver Maple, Red Maple, sumac, spirea, yew; as well as coreopsis, larkspur, foxglove, Coral Bells, hosta, poppy, columbine and pansy. Many vegetables are not attractive to them. A few plants act as repellents: catnip, garlic, chives, tansy and annual geraniums.

How can we manage Japanese Beetles to reduce their damage in our gardens and farms?

Cultural Methods: Like most pests, Japanese Beetles are attracted to weaker plants, so we can support soil health with organic matter, micronutrients, minerals, sufficient water and supplemental biology like mycorrhizae and beneficial bacteria. Plant resistant varieties and natives and xeriscape plants. The beetles are very vulnerable when the grubs are small. So xeriscapes that are watered deeply and sparingly will dry out the grubs and reduce their populations. Bluegrass can be allowed to go dormant in July to save water and seriously reduce grub population. Then water normally in September to bring turf out of dormancy. Or just follow CSU advice and “water as deeply and infrequently as possible.” Dr. Michael Klein, a Ohio State U authority on Japanese Beetles has stated that “compulsive overwatering is often to blame for grub damage.” He also recommends cutting grass to a 3” height, making it less attractive to egg-laying females. And he suggests that we do everything we can to prevent adult damage early in the season, because early feeding attracts LOTS of other beetles.

Non-toxic solutions for the grubs: Milky Spore is a bacteria that only affects grubs and must be eaten to work. Apply a teaspoon amount every 4’ and water in for 15 minutes. Though said to be effective, it may take a few years for adequate protection. It is best applied in early Aug/Sept when the soil temperature is above 65 degrees. Montana Cooperative Extension says it does not provide adequate control.

Nematodes of two varieties are effective but do not work in dry conditions, may not overwinter and are pricey.

Dr. Mike Klein recommends the aerator sandals called Spikes of Death. He says that whereas they are not effective for aeration, if you wear them while Dirty Dancing on your lawn in late Spring when the grubs are near the surface, studies have shown a better know-down than from chemical insecticides.

Non-toxic solutions for the beetles; these may not give total control: insecticidal soap, diatomaceous earth, neem that contains its active ingredient azadirachtin.

Some of our Boulder customers have had success with Veggie Pharm, a solution of vegetable oil, garlic, rosemary and peppermint; and a thyme based spray with Wintergreen called Garden Insect Killer by Liquid Fence is also said to kill the beetles.

Of course hand picking is effective. A bucket of soapy water can be held under the plant while knocking the beetles off into the bucket. This is best done in the early morning when the beetles are slower.

Lower toxicity solutions: Pyola-a combination of pyrethrins and canola oil, and other pyrethroid products do break down faster than more toxic pesticides, but they are still lethal to bees, birds, fish (and cats?). There are many variations.

Higher toxicity solutions: The Colorado Dept. of Agriculture says, “Historically this insect is a target for large amounts of insecticide use.” Organophosphates as well as Neonicotinoids are used. The Palisade Colorado population was nearly eradicated using two different neonics: Merit and Arena. But because neonics kill or undermine the health of most insects including bees, earthworms, lady bugs and beneficial insects, they are not a sustainable solution. And because they are systemic and always in the plant, they do not work in an IPM (Integrated Pest Management) program. Birds that feed on the beetles can also be killed.

Traps: using floral or sex-attractant scents do attract the beetles, but are not considered a solution since they usually increase insect damage.

Japanese Beetle is yet another foreign pest that does not have natural enemies here. Since it is new to us, we will have to watch, experiment and learn more to keep their populations below damaging levels.

New sightings of Japanese Beetle should be reported to the local CSU Cooperative Extension office.

Responding to the worst drought in 100 (300?) years has been confusing, disturbing and difficult. The main unanswerable questions are, “How long is it going to last?” and “Is global warming or other conditions going to cause this kind of drought to be more common place?” Implicit in these questions is the question being asked by water utilities, city governments and members of the Green Industry: “How much money should we invest in changes that will conserve water?” If in two years the drought is over and will not be this bad again for 100 years, then why bother to reinvent our utilities and businesses? On the other hand, if water providers, city councils and the Green Industry are not proactive about water conservation, and the drought cycle lasts for a long time, consequences could be devastating, and the public could get furious.

The Colorado State legislature is facing about 30 bills this session which focus on response to our drought. Some propose increasing our water supply. These include plans to repair dams and expand storage, drill more wells into the Denver Aquifer and the controversial and very expensive Big Straw Project. Other bills focus on water conservation measures and incentives. Since there is a limit to the amount of water we can keep adding to our supply, conservation is sure to be our main solution.

On the local level, the earliest responses to our drought were extreme and understandably not well thought out. Water utilities responded with restrictions that varied widely. Boulder imposed the most severe restrictions, starting in May and only allowing outdoor watering twice a week for 15 minutes per zone. To their credit, this approach did save 28% of normal use; however trees and gardens suffered, lawns were brown, and we don’t know the long-term effects. Other water providers waited too long to impose restrictions and so ran down their reserves which will necessitate severe restrictions in 2003.

Some responses to watering restrictions were not quotable and the poor water utilities people got blasted by angry homeowners and angrier plant professionals. Some businesses did, if fact, go under; and thousands of Green Industry professionals saw their income reduced greatly. The Turf Grass Industry in particular got blamed for using so much water and “causing” our water shortage. Because of the crisis level at which things needed to be done, it was a good thing that there was an organization in place to represent the Green Industry. GreenCo is a collaborative organization formed over 10 years ago, of nine plant professional organizations including the Colorado Nursery Assn. and the Associated Landscape Contractors of Colorado. The aim of GreenCo is to share information, improve communication between members and to provide a budget for big expenses like lobbying in order to represent Green Industry issues.

Why is this of any interest to gardeners? It may be as surprising to you as it was to me, that according to many water utilities, water use is prioritized like this:

1.Indoor water use is defined as essential (regardless of inefficiency and waste).
2.Business water use is defined as essential (this includes car washes, bottling companies and golf courses).
3.Landscaping is defined as non-essential (regardless of the impact on plant related businesses and homeowner investments in landscape). Therefore in response to a drought, the non-essential uses are cut off first. This is why the only mandatory restrictions were placed on landscape use. It is, of course, unfair that one segment of the community should make the sacrifices necessary to solve the water problem of the entire community.
The Green Industry then had a meeting with the Blue Industry (the water utilities) at which it was agreed there should be no bickering and blaming, and there were several hours spent on coming up with constructive solutions and establishing open lines of communication. I attended this meeting and although it was very civilized and constructive, I was surprised that xeriscape was only mentioned once by an audience member and drip irrigation was not discussed as a solution. Apparently both subjects are controversial and lack industry-wide approval.

Early in the debate, the Green Industry was understandably defensive. I kept hearing, “Plants don’t waste water; people waste water,” which does have some truth in it. And I heard one leader proclaim that like all other businesses, the Green Industry should get as much water as it takes to do business. Of course you can’t squeeze water out of an empty reservoir. Later on, the responses got less reactive and more constructive. Boulder had a public Drought Restrictions Review meeting in August and as a result, relaxed the restrictions to include a once a month tree-watering day. Both in Ft. Collins and Greeley, advisory groups were formed of Green Industry professionals, city staff and utilities staff to help design water use policy. This was a much friendlier and more intelligent approach that may be followed in Boulder and other communities. By the end of the year, some area-wide agreements were made about restrictions. For 2003, all major Front Range water providers will share this form:

1.A centralized information source to which all utilities will report their plans for watering restrictions.
2.All restrictions will limit watering to twice a week on the same schedule. (see box insert).
3.No watering 10am-6pm. Each utility will determine its own duration of watering and any particulars regarding hand watering, drip etc.
2003 Front Range Water Restriction Schedule

Sunday: Single family with even address

Monday: Special needs and permits

Tuesday: Multi-family and commercial

Wednesday: Single families with odd address

Thursday: Single families with even address

Friday: Multi-family and commercial

Saturday: Single family with odd address

No watering 10am-6pm

Five or six years ago, GreenCo organized a special task force to prepare for a potential drought. It is called WELL: Water Efficient Leaders in Landscape, and includes representatives from CSU Coop Extension, Denver Water, Colorado Water Wise Council, GreenCo members and others. In 2002, responding to the real drought, they developed a manual for use by Green Industry professionals which includes practices that are efficient and effective for water conservation. This resource is called Best Management Practices and was made available at the end of the season to all GreenCo members. The general public can also access this information on their website: www.greenco.org. In addition, GreenCo has outlined and begun carrying out a Water Efficient Landscape Action Plan. This plan has seven steps including data collection and sharing, researching specific plant water requirements, distributing conservation materials and giving training; and providing incentives to convert to water efficient systems and technologies.

Tom Ash, who has been hired by GreenCo as a water use strategist, is proposing that we can save a lot of water by using an ET controller that will automate irrigation scheduling. He has experience with this working in California. In a semi-arid climate like ours and especially during a drought, it is good to understand ET. ET stands for “evapotranspiration” and means the water quantity that evaporates from the soil plus the water that transpires from the plants. This quantity varies with temperature, humidity, wind and sun. An ET factor is usually expressed in inches and represents the amount of irrigation required to keep plants healthy. Since these calculations are all based on a Kentucky Bluegrass lawn area, I am not clear how it would apply to the needs of a xeriscape. In any case, this figure changes every day and represents the fact that a plant’s (a lawn’s) water needs are not the same every day. The problem is that irrigation systems are set to water the same amount every day, regardless of changing conditions, like rain. Tom’s ET controller is very sophisticated and can be calibrated to include soil type and slope. A radio signal is then sent daily from the weather station to the controller to adjust the watering frequency based on current conditions. Therefore the system will not run if it has been raining, it can reduce run-off by up to 50% and overall it saves water.

When water is cheap and plentiful, as it has been, it is customary to correct for inadequate coverage, poor design and even faulty equipment by over watering, which turf will often tolerate. However when water is restricted, the importance of well designed and efficient irrigation systems becomes obvious. Therefore, even though the ET controller probably works best for big lawns, it may turn out to be a useful water conservation tool.

Colorado Springs is an example of a city that made a very constructive response to the drought. Their restrictions began in mid June and tightened in September, and they saved 18% of normal outdoor use. The Colorado Springs Utilities Conservation Office, under the direction of Ann Seymour, adjusted restrictions to make them work for large properties, and they conducted commercial irrigation audits for large landscapes to help them use water more efficiently. They also ran an incentives program giving rebates to people who buy water efficient toilets and washing machines. (Even changing the toilets can save 10,000 gallons of water per year per household.) They also sent out helpful mailings with the water bills, ran an ad campaign, put conservation messages on billboards and had meter readers place door hangers with recommendations. They did not mandate industry to use less water, but encouraged them to do so and gave awards to those who were especially successful in conserving water. As a result, their winter water use was two million gallons a day less than the previous three winters. On top of that, they are changing the water supply to their electricity generation plant. Instead of using drinking water, they will soon have a pipe from the wastewater treatment plant to serve their electrical generators, which will provide tremendous savings.

One of the more common responses to watering restrictions was: “I could take care of my plants a lot better if you just tell me how much water I can use and let me water when and as long as I see fit.” Some people actually used more water under the restrictions, because they were afraid not to water when they were allowed. This brings up the subject of the Water Budget System. According to this method, each customer is given an allocation of water based on water availability, lot size and other possible data. The amount of water actually used is measured by the water meter, and feedback is given to the customer as to how well he met the budget. This method has many advantages; here are some of them:

1.Because different irrigation systems use different amounts of water in the same time period, time-based restrictions are less fair than the budget system which accurately measures water use by the meter.
2.Because water use can be measured, there is no need for “water cops”.
3.Gardeners could water according to the needs of their plants and according to when best fits their schedules.
4.Water budgeting puts emphasis on saving water indoors, which is about 50% of our water use.
5.It would raise public awareness of water conservation, and encourage investment in water-saving toilets, washing machines and water-wise landscapes. (People who change their old toilets for the new 1.6 gallon models will save 10,000 gallons of water a year. This water could then be used to save their trees, establish a xeriscape or even plant some roses.) This system does require an investment by the city in computer software, data entry and water bill redesign. However in the long run it is a powerful tool that would encourage the efficient use of water in both normal and drought years.
One more subject deserves notice. The water utilities are businesses that sell water. If they don’t sell as much water, they don’t make as much money. And even though they have water conservation departments within the utilities, anyone can see there is an obvious conflict of interests. One way they can save water and money is to reduce the peak demand, because that brief period of extreme use requires more infrastructure than it is worth financially. In any case they must be careful not to save water too fast or they could be in economic trouble. Increasing water rates have come to some cities and will be coming to other communities; this is understandable. Raising rates on the highest level of water use is also a conservation tool.

Other drought responses: CSU and CSU Coop Extension have constructed a Drought Website at www.ext.colostate.edu/menudrought.html ; the Denver Botanic Gardens will be hosting a Water Smart Gardening Expo on February 15; the ProGreen Convention for the Green Industry offered new classes in response to the drought; and Jim Knopf has poured out his research and knowledge at countless meetings, as only someone could who has been in drought-response training for the past 20 years.

Throughout all these responses to our drought, one theme seems to stand out and ask to be named, and that is the theme of waste, of the unnecessary uses of water that we have ignored because water has been so plentiful and taken for granted. In general, we have been over watering our landscapes, and we are told more plants have died from too much water than not enough. We have been flushing a pint of pee with five gallons of drinking water. Our washing machines use more water than necessary. We have stood by the sink or the hose with the water pouring out. We have cultivated a variety of lawn grass that needs too much water for a semi-arid region. We have run our electricity generation with potable water, and we have swept our driveways with a hose instead of a broom. We have allowed water leaks to spill precious water from faucets and reservoirs—and on and on. If we just cut the waste, we would already have enough water; maybe even in a drought.

Copyright 2003 by Mikl Brawner

Drought, Water Restrictions and Gardening: How Can They Go Together?

I think we were all caught off guard by this drought, by how fast we were forced to see dying trees and brown lawns and by the difficult discipline of watering restrictions. This was especially true in Boulder and Lafayette where mandatory restrictions began in May. Actually, 2002 is the third year in a genuine drought, which some of us without city water supplies can confirm. This year all around Boulder, Red Twig Dogwoods turned brown, linden leaves were scorched, Norway Maples suffered, many viburnums were looking very stressed, and trees in medians defoliated or died. Gardeners caught in the crunch between weeks of hot, dry weather and few opportunities to water, held off most of their planting projects; some started talking about moving away to where they could garden. For Denver and other Colorado cities, next year could be much worse.

Now begins the new education about growing plants while conserving water. We have some experience with xeriscape and its seven principles, but they are no longer enough; we have to go to the next level. We are going to have to be much more careful in our plant selection, and in grouping plants of similar water needs. We are going to have to give closer attention to microclimates: distinguishing the areas that bake from the areas that get some shade, recognizing south from east, noting the protective presence of a boulder, a tree, a shed, a downspout; and mapping the movement of the sun and the reach of the wind. We are going to have to learn how to use our water most effectively. We are going to have to learn more about mulching, about anti-transpirants, and about products and amendments that hold water longer. We may even have to adjust our idea of beauty to include dormant, brown lawns; more modest displays of flowers in the summer months and even dry and drooping foliage, stress and death. We will go through a transitional period which will be frustrating and painful, but then we will figure it out and our gardens will be better adapted. Even if we get our needed snow pack this winter, water conservation will remain a vital concern.

First things first: SAVE THE TREES. Trees in general are not very drought tolerant. We didn’t have urban forests in Colorado until humans started planting them and watering them. Yes, of course, we have cottonwoods and willows along streams and some boxelders too, but most of our trees, especially shade trees, are imported. On top of that, most irrigation systems are designed for turf and assume that if trees are growing in the lawn, they will be watered. In the first place, most turf is watered too shallowly (and Boulder’s 15 minute twice a week restrictions further encourage that problem); and secondly, when lawn watering is prohibited or limited, there is no system in place to water trees except by hand, which then takes too much time to comply with restrictions. Thirdly, trees in cities often have confined root systems, and are often overplanted with grass, perennials and other trees which compete for the water.

These problems became apparent in Boulder this year as trees in small median and parking lot plantings were the first to show stress. The newly planted trees with small and reduced root systems (as with ball-and-burlap trees), and the old and stressed were the main trees to die or defoliate. How the remaining trees are cared for in the coming year or two will be a matter of life and death; they are stressed and more vulnerable to pests and diseases.

Trees do take a lot of our water, but they save water too. This summer some of the only green lawns in Boulder were under trees. If global warming is happening, we will need at least some trees to save us from the heat, to keep the gasoline in our cars from out gassing in the parking lots, and to create moderated environments in which other plants can live. At this time, I will not go into the many values that trees add to our quality of life, but let’s not let our trees die while we’re trying to figure out how to save water. Remember the trees now casting our shade are twenty to a hundred years old; it will take that long to replace them.

Some trees that require little water are: Hackberry, Golden Rain Tree, Ponderosa and Pinon pines; Bur and Gamble Oak; Russian, Toba and Washington hawthorns. Trees with somewhat low water needs are: Silver maple, Green Ash, Honeylocust and Catalpa.

This drought has brought up some new and challenging questions:

1.Do trees take more water than they save? Which ones?
2.Is bluegrass a xeriscape groundcover if we can let it go dormant in the summer?
3.If my plants are dying under the current restrictions of 15 minutes twice a week, can I water once a week for 30 minutes to save them by watering more deeply?
4.If I buy a water efficient toilet which will save 10,000 gallons in a year, why can’t I have at least 5,000 gallons more that I could use for my gardens?
5.How can I recycle or reuse my water?
It is easier to come up with questions than solutions. To be fair to the municipalities, they were caught off guard as much as we gardeners, and it will be some years before they/we figure out how best to distribute our water. Even though my low-producing well has put me on water restrictions for the past 17 years, and all my gardens are by necessity xeriscapes, I wanted to get a broader perspective on this drought, so I asked some good local gardeners how they experienced this year’s water crisis.

I interviewed Lauren Springer, Marcia Tatroe, Bob Nold, Jim Knopf and John Spaulding:

“Did you lose plants to the drought this year?” Marcia lost dozens of plants, most of which were newly planted. Lauren lost both new and established, noting as did John and Bob that the losses were due to the cumulative effect of 2 or 3 dry seasons. Jim lost a few things.

“Were the losses due to the heat or mainly to the lack of water?” Lauren and Marcia thought both heat and drought, though Lauren said mostly lack of water. John said more likely heat because he was watering adequately. And Bob said his died because he was not paying attention to them. He also mentioned that his losses of alpine plants were very low, because they can continue to grow under a wide range of hot and cold temperatures.

In a recent talk, Kelly Grummons mentioned that in general, the metabolism of a perennial slows down above 80 degrees F and nearly stops at very high temperatures. A Boulder city forester told me that the burning leaves of the Norway Maples was due to their heat sensitivity, and it seemed that vegetable gardens that were planted early thrived and those planted late in the heat grew little until temperatures cooled.

“Name plants that did well this year with limited water supply.” Jim: Zauschneria, Buffalo Grass, Hesperaloe, Melons, Blue Mist Spirea, Junipers, Apache Plume; John: roses, and annuals did better under water restrictions where maintenance companies had been over watering

Lauren: Fernbush, Saltbrush, Rabbitbrush, Artemesia versicolor, Wright’s Sacaton, Salvia pachysilla, Apache Plume; Bob said all of his rock garden plants did well; Marcia: Desert Four O’Clock, Russian Sage, Apache Plume, Mt. Mahogany, Leadplant, Desert Mahonia.

“Name plants that died or did poorly.” Lauren: Veronica teucrium, all tall penstemons, carex; Jim: Red Maples, Sugar Maples, Norway Maples, Birches, High Bush Cranberry, Red Twig Dogwood; Marcia: Potentilla atrosanguinea, Ligularia, Eryngium alpinum, Microbiota decussata.

“Do you use a mulch? What do you recommend?” John suggests 2″ of coarse mulch applied only after the soil has been thoroughly watered. He says mulch that is too fine or too thick (4—8″) will not permit water to get through. Bob uses straw or anything organic, but prefers rock as the best possible mulch, allowing water to penetrate and then holding the water for a long time. Marcia uses mulch extensively, preferring pine needles loose or shredded, and chipper chips if they are re-shredded.

John Starnes says he has good results with a 6″ deep wood chip mulch.

“What were your water restrictions and how did they affect your garden?” Lauren’s well went dry May 7 and she had only 7″ of rainfall up to September, so she mostly watered trees, roses and woody plants. Marcia could water every third day as long as she wanted until Sept. and then one hour every third day. She only applied a half inch a week and that was enough. Her dry garden was only watered 3 or 4 times all season. She would prefer a water budget, watering when and how is best for her garden. Bob said his restrictions had no impact since he is used to having no rain and watering everything by hand. Jim noted that his water use went up with the restrictions. He did not like the shallow watering which resulted from Boulder’s 15 minutes twice a week rule. He would prefer more flexibility, measuring use by the water meter.

“Share an insight from your experience of this year’s drought.” Marcia: Most of my trees are small native trees and they did fine, but I recommend putting off tree planting until we see what next years’ water supply looks like. If you do plant one, choose one under one and a half inch caliper with a large rootball, mulch it 6″ deep beyond the width of the rootball, and water it once or twice a month over the winter, and be prepared to carry gray water to it next year.

John: When lawns are installed without proper tilling depth (8—12″) and without compost amendment, they will not be just dormant after a drought, they will be patchy at best or dead in two seasons of restrictions. It is best to start lawns of all types from seed so as not to get a horizontal barrier to water and nutrient movement. Even bluegrass, if done right, can be very disease, insect and drought resistant.

Bob: My bluegrass and turf-type tall fescue were both watered 15-20 minutes every ten days, and both look green and healthy. People should not be allowed to plant trees under water restrictions. Existing water supplies can’t possibly support more trees than we already have. Proper planting in the right place saves water.

Jim: Bluegrass won’t live on two tenths of an inch of water twice a week; patches of grass and bare ground is not a lawn; a half an inch of water once a week is much better. If we had a water budget system, that would allow more opportunities and use no more water. We could then design landscapes that fit the budget.

Lauren: Take care of the trees; this is our most important group of plants. We are lucky to have gardens, and here in Colorado you have to love gardening to put up with the duress, and to struggle with the obstacles. Colorado gardeners have to be tough and optimistic.

We may be going through a painful period, restricting our plant palette, and our freedom to water as we please, but this discipline is probably good, because the earth is not growing with the human population, and we must prepare for conservation of not just water, but of all our natural resources. A friend in Italy has a sign in her kitchen: “When you use THE WATER, give thanks. Can you imagine the world without her.” And another friend, a physicist at the Solar Energy Research Institute, believes a time will come when each person will get an energy allocation as well as a water allocation; and that we will have to make some hard choices between heating the house and miles of driving, for example. Mr. Bush may believe that we can keep coming up with cheap oil and keep sending ever more carbon dioxide into the atmosphere, but I’ll bet a lot of people are beginning to get the picture. As Chief Seattle put it: “The earth does not belong to us, we belong to the earth.” Statistically, average droughts are five years long. If that is true for this drought, we get two more years to figure things out and make adjustments with the pressure of this natural discipline. However droughts can be 10–15 years long, and besides, more houses are being built and so more demand will be placed on the same amount of water.

This may sound grim, but there are plants that are surviving this drought with even less water than restrictions allow: native plants, for example. And my xeriscape got only five waterings this year and still looks all right. And if I make some improvements, it will look even better. We can all share our successes and failures with each other and our gardens will get better adapted to drier conditions. Natural Selection is a ruthless and accurate designer. If, for example, all your Sunset Hyssop (Agastache rupestris) died from drought except one, and it flourished, it may have found the perfect spot, OR if it was seed propagated, it could have a slight genetic deviation that makes it more drought tolerant. So save your seeds from your best drought survivors and share them with your friends and neighbors. A drought cycle is the best time to cull the pretend xeric plants from the truly xeric plants, as well as to discover more drought tolerant strains. If we pool our seeds and cuttings, share our discoveries and insights, and follow these with real changes in our habit patterns and in our gardening, this drought could be a great education for better use of our precious resource: THE WATER.

In future issues of Colorado Gardener, we will go into greater depth on the drought situation and into practical approaches to gardening under drought conditions.

Copyright 2003 by Mikl Brawner

You may have noticed that the word “sustainability” is cropping up frequently these days. What does this word mean?, and why is it suddenly so popular? The word “sustainability” naturally means: the ability to sustain or to endure through time. And why is this idea so relevant to gardening, farming, economics, foreign policy, trade agreements, water use and automobile and product design? I think it is because the world can no longer ignore the reality of our earth’s limits. We humans have been going through a long adolescent period and now it is getting harder and harder to ignore the necessity of growing up and taking responsibility for our actions, and for the entire earth’s children. We have been burning our candle at both ends, acting like there’s no tomorrow, assuming our resources would last forever, thinking there is place called “away” where we could throw the waste and poisons of our expedient solutions. We have put cheap products and fast profits ahead of real essential values.

Now as the temperature of our earth rises and the human population swells, ground water levels are falling, and 40% of our waterways are not safe to swim in. Herodotus knew in the fifth century BC that “Man stalks across the landscape and deserts follow.” Today deserts in China alone are expanding at a rate of 2,150 square miles a year. This is not “gloom and doom”; this is the cool reality of the condition of our earth, as we have used and abused it, especially in the last 300 years. In this situation, when cooperation is most needed, the World Bank is extending loans to big corporations to buy up water rights, to privatize our water. These people are looking at us and thinking “tsk-tsk, their end of the boat is sinking; we’d better grab both oars so we’ll be in control.”

That is why scientists, citizen groups and people with a world view that is more grown-up and responsible, are talking about sustainability. It is time for all of us to learn to manage our resources and to care for all the human and non-human inhabitants of planet earth. Mathew Fox, spiritual leader, writer and teacher, has said “Sustainability is a contemporary word for ‘justice’; it is finding the living balance.”

But what has this got to do with gardening? Everything, of course. If there is not enough water to flush the toilet, we won’t be allowed to water our plants. (We remember 2002 !) If our gardening activities require too much petroleum for gasoline engines, chemical fertilizers and pesticides, we will likewise be restricted or cut off; or prices for plants and gardening products will become luxuries that only the rich can afford. If our gardening activities pollute too much as emissions into the air and poisons into the ground and groundwater, we will be cut off or restricted. And if you think I am exaggerating, know that water is now being called “Blue Gold” and that the more water is privatized, the more expensive it will certainly become. But enough about our desperate situation.

I think gardeners, by working with nature, life and death, the seasons and the weather, are already ahead of the crowd when it comes to understanding sustainability. Gardeners are nurturers, and it is the qualities of caring and mothering that are most needed to heal our planet. Who but the most oblivious, can still believe in the ‘Man’s domination over nature’ model of civilization?

Macho methods of controlling insects and diseases with pesticides have failed. Even the mainstream in agriculture and horticulture know this now and are practicing IPM (Integrated Pest Management), and in the US more and more agricultural toxins are taken off the shelves each year. Dominating nature with dams and big machinery may bring about short-term solutions, but the more humble approaches of conservation and efficiency are being recognized as powerful approaches, even by the utility companies. Top-down methods of manipulating our economies by subsidizing the burning of coal to produce electricity, subsidizing petroleum to provide power and energy, subsidizing each cow $2 a day to provide meat, and subsidizing huge corporations, are all showing long-term negative effects on the earth and on the earth’s peoples. But although we don’t often hear about it in the corporate-owned media, there are, fortunately, a lot of good-hearted, intelligent and far-sighted folks working from the bottom up for sustainability.

In October of 2003, the combined efforts of CU Boulder, Naropa University and a local business, Sustainable Village, organized and hosted The Sustainable Resources Conference. Over a thousand people from around the world presented and attended this event. Many of the speakers are working on projects which support sustainability for the benefit of the local people. And much of the value and excitement of this conference was the informal meetings and sharing of experiences, contacts and resources. For me, attending was the best antidote to the evening news in years. It provided such hope and good news of so many people acting compassionately and ecologically. Paul Hawken, who gave the last evening address, said that the sustainability movement is the largest grass-roots movement in history. Look for this conference in October of 2004, and visit their website at www.sustainableresources.org.

Hunter Lovins, well-know as a co-founder of the Rocky Mountain Institute, also spoke at the conference. Her latest project is called Natural Capitalism Inc. She has been advising the UN International Development Organization and a division of the World Bank about sustainable development. She has also co-founded a new business school of sustainable management at Presidio World College in San Francisco.

Paolo Lugari, another main speaker, has years of experience with building a sustainable community in Columbia, called Gaviotas. He believes that if human life does not learn to recycle carbon, nitrogen and oxygen, we could actually lose our protective atmosphere. Many of his innovative engineering designs were thought impossible, but function for the sustainability of Gaviotas.

Dick Chapin, who is going strong at 86, has a company that makes and distributes inexpensive and very efficient drip irrigation systems all over the world. His aim is to help people produce their own food, even where growing vegetables was previously impossible.

Closer to home, the Colorado Springs Utilities and CSU Cooperative Extension sponsored a symposium at the end of February on sustainable landscapes now and for the future, with presentations of sustainable landscape design, plant selection, installation and maintenance, for our semi-arid climate.Visit www.csu.org .

Denver Urban Gardens (DUG) is a nonprofit organization which fosters sustainability through community gardens, gardening and composting classes, and pulling together numerous agencies and groups to provide seeds, food and community. Their advice on watering and gardening is excellent, and their spirit is uplifting. Visit them at www.dug.org.

In Boulder there is the Center for ReSource Conservation, guiding Boulder County in the sustainable use of energy and natural resources. It has a recycled building materials outlet at the ReSource sales yard, its Garden in a Box program helps people plant a designed xeriscape garden, and they organize an annual Solar and Green Built Tour of Homes. Their website is www.conservationcenter.org.

Laura Pottorff, plant pathologist at CSU recently wrote an article in the Colorado Nurseryman’s Assn. newsletter entitled “How Sustainable is the Greenhouse Industry in Colorado.” She discussed the results of a survey to determine the adoption of Integrated Pest Management (IPM) in Colorado Greenhouse Operations.

People Planet Profit is an organization aiming to improve the quality of life for the current and future generation, through social responsibility in Colorado businesses. (www.P3Colorado.org)

And just one more: The Bioneers conducted their first simulcast of their annual event at CU Boulder last October. Each year their conference gathers visionaries with practical solutions for restoring the earth. The simulcast magnetized a Boulder conference of many people in our local area also working on sustainable solutions.

These examples are just the tip of the iceberg of sustainable workings these days. Many more people are responding to both the crisis and the business opportunities of changing how we garden, live, do business and relate with our neighbors.

In the next issue, Mikl will conclude this article on sustainability with specific suggestions that can guide you in the direction of sustainable landscaping.

TIME FOR SUSTAINABILITY

In the last issue, I discussed the reasoning behind the importance of learning to manage our resources, including water, sustainably. And I mentioned several individuals and organizations that are doing good work in helping us to manage resources, provide food, and in general, take care of not just a privileged minority, but of the whole earth. The ability to sustain life into the future should be a goal we can all agree on.

Now I would like to bring this subject down to earth by making a few suggestions that can guide you in the direction of sustainable landscaping.

1.Use plants that are regionally adapted, i.e., that love to grow in Colorado: natives, xeriscape plants, most herbs, many rock garden plants and shrub roses are examples.
2.Eliminate or seriously reduce your use of pesticides, fungicides and herbicides. There are now many alternatives to toxic biocides, which are designed to kill life and don’t know when to stop killing. They destroy the natural support system of the earth: the earthworms, beneficial fungi and mycorrhizae, beneficial bacteria and beneficial insects that help maintain the health of the garden. A basic principle is: don’t use any controls unless the damage exceeds a significant level. A few pests just feed the beneficial insects. “The investment in seeds of plants that bloom through the summer, will give you more pest control that the same amount spent on pesticides.” Stuart Hill, McGill U. (This is because they support the beneficial insects.)
3.Reduce your lawn area if it is water-thirsty bluegrass, OR let it go dormant in July and August, OR convert it to native and drought-tolerant grasses, OR plant flowering groundcovers as edging along sidewalks and driveways, or on steep slopes and in shady areas where grass is not doing well.
4.Xeriscape your landscape: plant water-thrifty varieties, put plants of like water needs together, use efficient irrigation methods and mulch. This may sound like a lot of work and money, but so much can be done a little at a time. It can be fun and you’ll be better prepared for the next dry spell or drought.
5.Don’t just feed the plants; feed the soil. More and more research is showing that the old NPK (nitrogen, phosphorus, potassium) formula has limited significance. Even though it is true that these elements are important to fertility and plant growth, equally important is the soil life: the millions of soil bacteria, soil fungi/mycorrhizae, earthworms, etc., that break down organic matter into plant food and make minerals and even water more available to the plants. So feed these little guys what they need, which is organic matter: compost, manure (if it is low in salts), shredded leaves, coffee grounds, etc. Learn how to compost; turn your garbage into gold. This is one of the true alchemies of sustainability.
These are just a few suggestions. If you would like to share other practical solutions for sustainable landscaping, send them to the Colorado Gardener at .

The world may be at a crisis level; we may be losing 10,000 species a year. And we may feel helpless that our government won’t sign the Kyoto Protocol or the Earth Charter (www.earthcharter.org), but we have more power than we think. Where we shop and how we shop is also whom we support and what we support. We can vote with our dollars to design out toxicity and waste in manufacturing and in our environment. If we want our children to inherit the earth, we can do this.

We can change our landscapes so they require less water. We can rely more and more on renewable resources. We can change our standard of beauty from the Eastern (English) image of the lush green perfectly mowed lawn where only one kind of plant is allowed, to a western image of a lush mix of silvers, blues and greens with flowering perennial plants, native grasses and tough shrubs. We can do this not only because we don’t want our landscapes to crash when there is a water shortage; we can also do it so there is more water left to grow food, and for drinking water for people in Mexico. Mathew Fox said at the Sustainable Resources Conference, “Compassion is not about feeling sorry for others, but about feeling together with others.”

What each of us does in her/his own private garden, makes global ripples. We need to recognize that “what comes around goes around”, and that as our world gets smaller and smaller, we inadvertently influence, poison or support each other by our purchases and by our actions. Our survival as a human species and as a planet, is dependent on us growing up to a more global and ecological perspective. Changing our mind, our view and our habits is never easy. But we gardeners are accustomed to working with the realm of living things sustained through time, and we love to learn what’s new.

Waterwise Shade Trees 40—75′

Natives

1. Populus acuminata-Lanceleaf Cottonwood
2. Salix amygdaloides-Peachleaf Willow
3. Celtis occidentalis-Western Hackberry
4. Fraxinus pennsylvanica-Green Ash
5. Pinus ponderosa-Ponderosa Pine
6. Pinus flexilis-Limber Pine
7. Pinus contorta var. latifolia-Lodgepole Pine
8. Pseudotsuga manziesii var. glauca- Rocky Mt. Douglas Fir <!–[if !supportEmptyParas]–>

Non-Natives

1. Catalpa speciosa- Western Catalpa
2. Gleditsia triacanthos- Honeylocust
3. Quercus macrocarpa-Burr Oak
4. Gymnocladus dioicus-Kentucky Coffee Tree
5. Acer saccharinum-Silver Maple
6. Aesculus hippocastanum-Horsechstnut
7. Trash Trees”: Black Locust, Siberian Elm, Tree of Heaven, Boxelder (a native) are serviceable as frontier trees
Waterwise Ornamental Trees 15—40′

Natives

1. Acer glabrum-Rocky Mt. Maple
2. Celtis douglasii-Canyon Hackberry
3. Acer grandidentatum-Bigtooth Maple
4. Fraxinus anomala-Singleleaf Ash
5. Prunus americana-American Plum
6. Prunus virginia-Chokecherry
7. Quercus gambelii-Gambel Oak
8. Quercus undulata-Wavyleaf Oak
9. Robinia neomexicana-New Mexico Locust
10.Ptelea trifoliata-Hoptree; Wafer Ash
11.Populus tremuloides-Quaking Aspen
12.Pinus edulis-Colorado Pinon Pine
13.Pinus aristata var aristata-Colorado Bristlecone Pine
14.Juniperus scopulorum-Rocky Mt. Juniper
15.Juniperus monosperma-Oneseed Juniper
16.Cupressus arizonicus-Arizona Cypress
Non-Native Ornamental Trees 15—40′

1. Acer ginnala-Ginnala Maple
2. Crataegus ambigua-Russian Hawthorn
3. Crataegus ‘Toba’-Toba Hawthorn
4. Crataegus phaenopyrum-Washington Hawthorn
5. Morus alba tatarica-Russian Mulberry
6. Pyrus ussuriensis-Ussurian Pear
7. Koelreuteria paniculata-Golden Rain Tree
8. Prunus padus-May Day Tree
9. Sophora japonica-Japanese Pagoda Tree
10.Syringa pekinensis-Peking Lilac
11.Syringa reticulata-Japanese Tree Lilac
12.Rhus typhina-Staghorn Sumac
13.Aesculus glabra-Ohio Buckeye
14.Cotinus obovatus-Smokebush
Copyright 2003

Roses are certainly one of the world’s most beloved flowers, and yet many people have given up on them because they have gotten the reputation of needing frequent spraying, feeding and fussing. They got this reputation because for decades, hybrid tea and floribunda roses were bred mostly for special colors, a particular flower form and repeat flowering. Their value was judged more for the exhibition table than for the garden. Now, as more people have become aware of the dangers of pesticides and as the trend has moved to “care-free” shrub roses for the garden, rose breeding has shifted in the last ten years towards more sustainability. Now Texas A&M has a program to test and promote “Earth Kind Roses”, and the rose “Knock Out” has recently taken the rose world by storm, not because it is such a beautiful flower, but because it repeats so well and requires no disease control. Even I, who am mostly interested in xeriscape, natives and Colorado-adapted plants, have come to specialize also in roses because I have been won over by more than a hundred varieties that measure up to my strict requirements for Colorado sustainability.There can be no objective standards for sustainability since all gardeners have different standards, different gardens and varying time and effort available for gardening. But I will offer one approach. To begin with, a sustainable rose shouldn’t act like an annual. Maybe a hundred years lifespan is a bit much to expect, but I think a sustainable rose should perform well for at least ten years.

Secondly, a sustainable rose should be resistant to diseases and have few pest problems. We gardeners should not have to put on a protective suit and spray poisons every 3 or 4 weeks to have nice roses. I think we shouldn’t have to spray more than one or two (maybe 3) times a year, and then we should only spray with water or a mild, non-toxic type of spray. We are fortunate in Colorado to have low humidity and therefore fewer fungus diseases. And more and more varieties are available that are disease resistant.

Another quality of a sustainable rose is that it should be a strong plant that doesn’t need to be pumped up every few weeks with a chemical fertilizer. Chemical fertilizers can be harmful to our soil life and can induce pest and disease problems because fast growth leads to soft tissues; and as the price of petroleum goes up, so will the price of petroleum-derived fertilizers. At Harlequin’s Gardens nursery, we feed our display roses twice a year with a good quality organic fertilizer. Wild (Species) roses don’t need feeding, and the spring-only bloomers only need one feeding a year. Repeat-blooming roses perform better when they are fed twice a year.

A sustainable rose should be able to survive difficult conditions and still perform reasonably well. In Colorado that means a rose has to be able to handle wind, heavy clay and lean soils, some drought, heat, intense ultraviolet radiation, and rapid temperature changes. Many roses that do well in other parts of the country will not pass these tests. There are, however, roses growing in cemeteries and alleys that have survived here for decades, others that have persevered through wars and neglect since the Middle Ages, and also modern shrub roses that thrive here. Of course, what is sustainable and what a rose can endure is relative to the particular location and to the amount of care the gardener wants to give.

And the last characteristic of a sustainable rose is that it must be cold hardy. Many Hybrid Tea and Floribunda roses that are hardy enough for the East and West Coast and the South, won’t pass the ten year test in Colorado, but a few will. And beware the “hardy to Zone 5″ promise, because many companies and authors that are unsure of hardiness will say “Zone 5″. Even if a rose will survive 20 below zero, survival depends on when the freeze comes. If a rose has gone dormant and has acclimated to cold temperatures, it is ready to handle a deep freeze. But if the rose is still growing and blooming late in the fall (like we love to see in the Hybrid Teas and Floribundas), or if it begins growing too early in the spring, then our rapidly changing Colorado temperatures can cause considerable die-back or even death.

This brings up the subject of own-root roses. Most of the Hybrid Tea and Floribunda roses that are available commercially are grafted. A single bud from a rose is grafted onto the stem of a seedling rose. This quickly produces a rose for sale, but has numerous drawbacks in terms of sustainability. The graft union is the most cold-sensitive part of the plant, so if it freezes and the upper rose dies, only the root-stock will come up in the spring, not the rose you bought. Also when the entire plant grows from one stem, it cannot renew itself from the root if the stem gets damaged or diseased or gets too old. However if a rose is grown from a cutting and produces its own roots, then it can renew itself possibly for a hundred years. It has more resistance to cold, it generally produces more flowers because it has multiple stems coming from the root, and if it should die back to the ground or get accidently cut off, the variety you bought will sprout from the root. It used to be hard to find own-root roses, but by gardeners’ demand, they are becoming more common. Nearly all Canadian-bred roses are produced on their own roots, because Agriculture Canada has done field trials that prove the higher success rates of own-root roses in cold climates.

Now I would like to give a few examples of roses that are sustainable in Colorado. There are several species of roses that are native to Colorado including Rosa woodsii and Rosa acicularis, but even these need proper siting and/or some water. And truthfully, though species roses are beautiful, many survive by suckering aggressively so are mostly valuable for wildlife areas, the back corner and for bank stabilization. There are other species roses that are well adapted to Colorado, like Rosa eglanteria and Rosa glauca. Rosa glauca, the Redleaf Rose, may seed a little, but it does not sucker aggressively. It has a high American Rose Society rating because it looks good in all seasons. Foremost is its foliage which is a very unusual and beautiful reddish-purple all season long. The spring blooms are small, mauve flowers and following them are copious red hips that last into winter and are showy against the snow. It will grow 5—5′ or a little bigger, is tolerant of poor soil, shade and some drought.

Also sustainable are many of the heirloom roses. The Gallicas can sucker like a wild rose, but usually not as aggressively. They would be my choice to plant by a grave stone, since their suckering can help them evade lawn mowers and herbicides. One of my favorites is Complicata. It is a 7—7′ shrub with long arching canes and large 4″ bright pink single flowers. Yes, it only blooms in the spring, but I pair mine with an old-fashioned Mockorange, and when they bloom together, the effect is stunning. It appreciates the little care I give it, but could undoubtedly survive on its own. Other heirlooms that ask little and give a lot are the Alba roses, like Felicite Parmentier; the Damasks, like Madame Hardy; the Mosses like William Lobb; and the ferny-leafed roses like Father Hugo. Don’t discount these sustainable beauties, just because they are only spring blooming; they are often tougher than the repeaters.

There are also heirloom roses that repeat their flowering and are sustainable. One of these is Sydonie. It is a vigorous 5—6′ shrub with very double medium pink flowers that are very fragrant. It is hardy and has a very reliable and profuse repeat bloom. (It was said to be the favorite rose of Dr. William Campbell, who founded the High Country Rosarium). Others include Rose de Rescht, Marchesa Boccella and Stanwell Perpetual.

The early climbing roses were the ramblers which, though almost all bloom only in the spring, make up for it with huge volumes of blooms. One of these is Paul’s Himalayan Musk. I warn people that it has vicious hooked thorns and covers trees and small buildings, but the pendulous clusters of sweetly fragrant lavender-pink blossoms and the romance of it makes them ignore my warnings. I get to suffer through pruning the one pictured, which overwhelms the apple tree at our house where it stops traffic when in bloom. Francis E. Lester and Lawrence Johnston are also reliable ramblers.

In the group called Shrub Roses, there are many that are sustainable. One of the oldest and best in that category is Seafoam. It grows 3′ high and 4′ wide and has small double white flowers that repeat all season. It is very tough and tolerates difficult conditions well. During the drought of 2002, I saw one in a median strip where nearly everything else had died, and Seafoam was still blooming. Golden Wings and Linda Campbell are other sustainable shrub roses.

The Canadian Roses are classified as shrub roses, but we give them a separated category. They were bred in Canada to be repeat flowering, disease resistant and very cold hardy to at least Zone 3. Two years ago when winter conditions caused many roses to die back, the Canadians had little damage. In particular, most of the best climbing roses for Colorado are Canadian Roses. Two favorites are John Cabot, growing 8—10′ with orchid pink flowers, and Henry Kelsey, growing 6—8′ with red semi-double blooms which fade to a pink-red. Both tolerate some shade, poor soil and stingy watering. Other good Canadian roses are Morden Blush, Winnepeg Parks, John Davis and Morden Sunrise.

David Austin’s English Roses are neither the hardiest, nor the most disease resistant, but on their own roots, many have performed very well in Colorado. They have really beautiful flowers and are often wonderfully fragrant and most repeat very well, so they are worth a little extra work. We have been growing Abraham Darby at the Boulder-Dushanbe Teahouse for 8 years very successfully. It makes a dense shrub 5′ tall and wide with 4—5″ voluptuous double flowers that are a soft-pink shading to apricot in the center. The fragrance is a strong old rose mixed with a delicious fruitiness. It has excellent repeat bloom and has proved a strong performer. Golden Celebration, Jude the Obscure, Wise Portia, Wenlock and others have done well here.

Like the native roses, the “Found Roses” have survived decades of Colorado’s trials by fire and ice. These are roses salvaged from cemeteries, alleys and old homesteads, which are lost to commerce, obscure or unknown. Most only bloom in the spring, but have proved their sustainability and worth. One of these is Desiree Parmentier. It is found in many local communities, growing 4′ high and up to 6′ wide. The medium pink blooms are very double with a green eye, and are deeply and powerfully fragrant with old rose perfume. It may only bloom for 4 weeks but tolerates poor soil, drought, considerable shade and is completely winter hardy. It does sucker a little, and you may think “Oh, I don’t want a roses that sucker, they are a nuisance.” And you may be right. But suckering is a very sustaining strategy. For example, if the roots find more water east of the original plant, the sucker that comes up on the east side will prosper and move the plant in a more sustainable direction. Other enduring “Found Roses” are “Banshee”, “Fairmount Proserpine”, and “Pine Street Tricolor”.

These are but a few of the roses that can glorify our gardens sustainably. They may be a little more trouble than hardwood shrubs, but their other qualities reward us for our efforts. Roses grow quickly and recover from damage quickly, their beauty can touch our hearts, their fragrance can melt into our soul, and many can flower repeatedly. Now we can find these qualities in sustainable roses that are easier to maintain and whose care is kinder to our Earth.

Normally when we think of fungi relating to plants, what comes to mind is infection and disease: powdery mildew, blackspot, slime flux and canker; Oh, NO!! However there is a growing awareness of the far more extensive benefits that fungi contribute to our world. Decomposing fungi are primary agents in the composting process which to us recyclers is the magic of turning garbage into gold. Not only do our plants love the rich humus and organic matter, but pesticides and herbicides are also broken down. Much of the body of soil itself is made up of fungi, especially loamy, well-aerated soil. And then there are the symbiotic fungi, the ones forming mutually beneficial relationships with plants. These associations of absorbing roots with fungal mycelium are known as mycorrhizae, from “mycor”- fungus and “rhiza”-root. Even though these beneficial relationships were discovered in 1885, it is not widely known today that 95 % of all plants on earth intermingle their roots with mycorrhizal fungi.

Vera Evenson, local author of Mushrooms of Colorado, has called this interweaving of various species of trees’ roots with various species of fungi “a marriage underground.” She explained that fungi lack the chlorophyll which allows green plants to make their own food out of sunlight, carbon dioxide and water in the process of photosynthesis. Instead they are more like animals in that they must get their nutrition from already-made carbohydrates and amino acids. And so for millions of years, fungi have made relationships with plants: some parasitic which can harm or kill the host plants; some saprophytic, living off the tissues of dead plants; and some symbiotic, like the mycorrhizal fungi which benefit plants. Of these, most enter the cells of absorbing roots forming endomycorrhizae, and some form sheathes on the roots forming ectomycorrhizae.

To think of these mycorrhizal fungi as “infecting” the roots of plants is to underestimate the mutual evolution that derived these specialized relationships. The natural world is a highly competitive environment where few of the seeds that germinate reach maturity and fewer still live long and vigorous lives. One of the primary structures of survival for a plant is an extensive root system, and here is where the mycorrhizal fungi expand the concept of “survival of the fittest.” Usually we think of this Darwinian concept as symbolizing the struggle of the mightiest to the top of the gene pool. However all sorts of alternative strategies have proved successful: the skunk, the turtle, the tapeworm and the human, to name a few. In this case, the successful strategy was non-aggressive mutual aid.

Millions of years ago trees were putting out roots into lean soils and there, beneath the earth, these roots met with the hollow, threadlike mycelium of fungi; and both were looking for food. The fungal mycelium being more branching, fine and extensive are far more efficient than roots in contacting the soil, expanding the surface of a root sometimes by 700%. Therefore in economic terms (which a surviving plant is desperate to consider), an investment of 10-20% of its carbohydrates, vitamins and amino acids in the development of symbiotic fungi will give a return of over 100 times the value of that investment in root-like development. Plus these mycorrhizal fungi are able to mobilize complex nutrients otherwise unavailable to plants. The trees, of course, made the obvious right choice: “Give the little suckers a place at the table.!” Thus began the marriage made in earth.

This marriage continues today to benefit plants. Dr. Donald H. Marx, a leading scientist who founded the Institute for Mycorrhizal Research and Development for the US Forest Service stated that through this alliance with plants:1) the fungi bring water, sometimes from as far as 30′ away, to the roots making the plants more drought-tolerant. 2)the fungi bring minerals essential to plant health to the roots: phosphorus, nitrogen, zinc, manganese and copper. 3) the fungi present physical and sometimes antibiotic barriers to root pathogens, thereby preventing diseases. 4) they increase the tolerance of plants to extremes in soil temperatures and pH. 5) they increase the longevity of absorbing roots. 6) they help plants tolerate stresses like transplant shock, soil compaction, soil toxins and heavy metals.

Dr. Marx points out that even though mycorrhizae are already present in city soils, both the numbers of species and the numbers of fungi present are less than one fourth of what they should be for good plant health. In addition, native mycorrhizae typically only benefit native plant species. For these reasons, and  because of the many stresses on plants in urban settings, why not introduce supportive fungi? He believes this is especially important for newly planted balled-and-burlap trees that are dug in the fields, which reduces their root system by 70%-90%. Here the fungal mycelium can form a “secondary root system” much more quickly than the actual roots, to prevent stress-related diseases and pest problems. The addition of mycorrhizae in a multiple-species cocktail has been the most beneficial reclaiming mine sites, deserts and arid locations, nutrient-poor and depleted soils and subsoils as are found around many new homes. Dr. Marx added that sticking a tree into a barren soil is like trying to raise a polar bear in Florida.

Paul Stamets, another pioneering mycologist and author of Mycelium Running, acknowledges dramatic benefits from these fungi. He has studied how a continuous network of one mushroom can connect many acres of a forest, creating a kind of “web” intelligence where the “mycelium guards the forest’s overall health, budgeting and multi-directionally allocating nutrients.” This is not an airy-fairy idea. Because the fungus is connected to the whole area, it has an interest in the prosperity of the whole forest, upon which it is dependent.

Rob Reinsvold, a mycologist and biologist teaching at the University of Northern Colorado in Greeley, believes that if the mycorrhizae already present in the soil are given more supportive conditions, they will populate in larger numbers. Conditions which support mycorrhizae also support other beneficials like soil bacteria and earthworms. These conditions include: mulching, incorporating composted organic matter, keeping the soil moist but not soggy, fertilization with slow-release organic fertilizers or low doses more frequently, and avoiding habitual use of fungicides and pesticides.

Just in the last 10 years many companies have sprung up selling mycorrhizal fungi products to nurseries and gardeners. However there are many differences of opinion as to their effectiveness. Lakshri Sridharan, who has a PhD in microbiology says, “Initial investment on mycorrhizae may appear to be a little expensive, but inoculations with mycorrhizae will save money on water bills, chemical fertilizers, pesticides or fungicides.” But Christina Wells at Clemson University said of her research, “In general we found little benefit from mycorrhizal products, as all products purchased through typical consumer channels contained no living inoculum.” One of the problems is that mycorrhizae are living beings that may dry out on the shelf of a garden center or overheat in direct sunlight.

From my own research, there appears to be several atypical sources for mycorrhizae that may have good viability. Some of these are: Organica Biotech, Plant Health Care, Inc., Mycorrhizal Applications, Inc.,  BioLynceus and Eco-Cycle Compost Tea.

But the latest hot tip comes from Tom Selvig, a heartful microbiologist with many years of experience in the field. He says that mycorrhizae can be increased the most rapidly in association with photosynthetic bacteria that can not only fix atmospheric nitrogen, but also change raw materials into sugars that feed the fungi. These bacteria can rapidly adapt to new environment and can dramatically improve conditions for fungi and plants. He emphasizes that it is not just elements like N-P-K that support plant life; it is biological life.

There seems to be a theme already characterizing the 21st Century: nothing stands alone; everything is interconnected. If a boat is sinking, it isn’t “his” boat it is our boat. Likewise the more we learn about how soil life works, the better we can design sustainable systems for plants, and therefore, for us humans who are dependent on plants. Mycorrhizae may indeed be very beneficial for plants, especially in stressful conditions, like much of the West, and especially if temperatures are rising. But we must not forget that fungi are just one of many populations of microorganisms that constitute soil life. These emerging revelations emphasize the old gardening dictum: “Feed the soil, not the plants.”

At our nursery it is not unusual for people to ask us for plants that “bloom all the time”. And we have to admit that most perennial plants only have one sexual cycle per season, and that for a garden to have truly continuous bloom, we must include spring-blooming plants, summer-blooming plants and fall-blooming plants.

In addition, there are a few other important issues to mention regarding the quest for long-blooming perennials. One is that “long-blooming” should be included in the larger subject of “long seasonal interest” which can include foliage color, interesting textures, contrasting forms, evergreen and ever-silver, sculptural elements, fall color, and attractive fruits, seeds and bark. It is also relevant that long-blooming can sometimes mean short-lived because the plants’ strategy to produce a lot of flowers resulting in a lot of seed, can exhaust the plants.

Also, as the country song goes, “Spring would be a dreary season, if there was only Spring.” Change is exciting; only if some things stop blooming does visual space open up to appreciate the emergence of a new bloomer. And opening to seasonal change helps us to internalize Nature’s wisdom of cycles, so we don’t expect constant blooming from ourselves and others. And lastly, bloom time can be lengthened with cultural methods such as watering adequately during bloom time, increasing soil fertility for some species, and not for others; and removing spent flowers before seed takes energy from the parent plant.

However, there ARE perennials that have exceptionally long bloom times. Here are five good ones that are easy to grow and that thrive in the Denver metro area:

Erodium chrysanthum, Yellow Storksbill, makes a compact mound of lacy gray-green leaves, 6″ high and 12″-24″ in diameter. The typically pale citron-yellow, five-petaled, geranium-like flowers rise a few inches above the foliage on thin stems. The spring bloom is strongest, followed by some reblooming the rest of the summer. Supposedly there is a female form with sulfur yellow flowers that blooms even more freely. This is a very drought tolerant plant that although it is not well known, has a history of dependable success in the Denver area. Yellow Storksbill is also an elegant and well-behaved plant for the front of the border, along a path or as a specimen. Its gentle texture and subtle color makes it a good foil for bolder colors and forms such as Scabiosa caucasica (Blue Pincushion Flower and Aquilegia chrysantha (‘Denver Gold Columbine’)

Plumbago (Ceratostigma plumbaginoides) is a tough and drought tolerant ground cover that blooms a very long time from summer into fall, and then dazzles us with deep red fall foliage color. The flowers are an intense dark blue. The attractive shiny green foliage disappears in winter and doesn’t return until early May. This is a long-lived and dependable plant in a variety of soil types and in part-shade or full sun. It grows 6″-10″ high and spreads 24″-36″ or more into drifts that can weave with other plants. It has exceptional value underneath trees in dry shade.

Geranium ‘Rozanne’ was chosen as the 2008 Perennial Plant of the Year because of its large violet-blue flowers that bloom “continuously” from late spring to mid fall. The flower is 2 ½” in diameter with purple-violet veins and showy white centers. It can grow 12″-24″ high and wide and its dark green leaves turn red in the fall. It was discovered in England, but the Perennial Plant Association chooses plants that are adapted to a wide range of climates and conditions, and it is claimed to be heat and drought tolerant. It has been tested in the US and is said to have one of the longest bloom times of any of the hardy geraniums. Like most hardy geraniums, ‘Rozanne’ has no serious pests and requires little maintenance except to shear it 3″ in August. It could even be a good candidate for a container.

Chocolate Flower, Berlandiera lyrata, is a native of southern Colorado and the Southwest that blooms from early May through the summer. Its bright golden yellow daisy flowers really do perfume the air with the fragrance of chocolate. This pest-free plant grows to 12″-16″ high and can be 18″-30″ wide. It withstands heat waves, full sun, drought and a variety of soil types. However, Chocolate Flower does not stand over-watering, so if the flowers droop in the afternoon, understand that this reflex is a natural reaction, not a cry for water. The seed heads are ornamental and can lead to some self-seeding. This is a good plant for a xeriscape, shrub border or meadow.

Papaver croceum is a very attractive form of Iceland Poppy, Papaver nudicaule, which has naturalized in the Colorado mountains around old mine sites. The form available locally blooms from early spring through the summer with 2″ bright lemon yellow, cupped poppies on wiry stems 12″-16″ tall. The gray-green hairy foliage makes an attractive evergreen rosette. This lovely and delicate flower is drought tolerant, adaptable and even holds up to the wind. It can be grown in full sun or part-shade and can form charming colonies if allowed to self-sow.

LIST OF LONG-BLOOMING PERENNIALS

Gaillardia aristata – Indian Blanket Flower

Oenothera caespitosa – Tufted Evening Primrose

Oenothera macrocarpa – ‘Silver Blade’ etc

Mirabilis multiflora – Desert Four O’Clock

Calylophus hartwegii – Sundrops

Viola Corsica – Corsican Viola

Hymenoxys scaposa – Sundancer Daisy

Datura wrightii – Sacred Datura, Angel’s Trumpet

Gaura lindheimeri – Whirling Butterflies

Linum flavum – Golden Flax

Penstemon rostriflorus – Bridges’ Penstemon

Penstemon richardsonii – Richard’s Penstemon

Penstemon mexicale ‘Red Rocks’

Penstemon pinifolius – Pineleaf Penstemon

Saponaria ‘Max Frei’- Max Frei Soapwort

Dianthus nardiformis

Argemone polyanthemos – Native Prickly Poppy

Callirhoe involucrata – Prairie Winecups

Diascia integerrima ‘Coral Canyon’

Salvia greggii – ‘Furman’s Red’ & ‘Wild Thing’

Glaucium acutidentatum, G.flavum etc

Sphaeralcea – the taller species

Scutellaria supina

I know of one lilac that has some repeat flowering in the fall, but I’m not aware of any spireas, mockoranges, shrub honeysuckles, forsythias, serviceberries, butterfly bushes, rabbitbrushes, cotoneasters, or other shrubs that repeat their flowering cycle. Why is it, then, that many gardeners demand continuous flowering roses ? We want them, of course, because they exist.

The fixation on constant flowering is encouraged with annuals, which, of course, don’t really start blooming until late spring or summer and then the first winter, they die. And seasoned gardeners know that the search for perennials that “bloom all season” leads to the proper selection of many species that will bloom in succession. So when we hear of roses that bloom from May or June through September, we think we have found the holy grail. However there are qualities besides repeat flowering which could entice us to cultivate the so-called “once-blooming” roses. I would like to share these not-so-obvious reasons with you.

For several hundred years, before anyone understood the functions of the different parts of a flower and how to manipulate them to create hybrids, roses were selected for the beauty of their bloom, fragrance, color, shrub form and hardiness. It was not until the mid 1700s that roses began to be bred for repeat flowering, and this achievement has been made with some significant costs. It is important not only what breeders select for, but also what they don’t select for.

So before we leap to the conclusion that repeat bloomers are superior to the “once-bloomers”, take a look at some other qualities. For example, when a rose has only one bloom period, it often produces as many or more flowers than a “continuous” bloomer will make in a season. This means that when it is in bloom, the spring bloomer will create a floral effect, which is not only beautiful, but exuberant, breath-taking, atmospheric, magnificent and splendorous. Such environmental effects can be experienced by the spring-blooming “Banshee”, Fruhlingsgold, Alba Suaveolens, Complicata, Paul’s Himalayan Musk, Scharlachglut and Father Hugo, and the summer-blooming Rosa setigera.

Not only do these masses of roses create powerful romantic and sensual effects, but many “once-bloomers” capture the heart with the exquisite beauty of their flower forms. Whereas the Meidiland roses create masses of color that are very impressive from a distance, the individual flowers lack the great beauty of many of the heirloom roses. For instance, I know few women who would choose a bouquet of Meidiland flowers over the classics Madame Hardy, Felicite’ Parmentier, William Lobb, Constance Spry, Ispahan, Reine des Violettes, Belle de Crecy and Variegata di Bologna.

And then there is fragrance. The modern urge for more flowering forgot for the most part to include fragrance. We have become a very visual society, and fragrance was thought for many years to be less important in rose breeding than color. Consequently the heirloom roses are generally more fragrant that the hybrid teas, floribundas and landscape roses. And the intensity of the scent is only part of the experience; the quality of the scent is very important. Fragrance is difficult to rate and to define because it is so individualistic. A scent that is strong to one person may not be perceptible to another, and a fragrance one person finds pleasant, will be unpleasant in the nostrils of another. However many of the “once-bloomers” have fragrances which have great universal appeal at a fundamental level. For instance, it is not unusual for someone smelling the very fragrant hybrid tea rose ‘Double Delight’ to say “That’s very nice”, but upon smelling the Apothecary’s Rose to exclaim simply, “Whoa !!”. This old rose, also known as Rosa gallica officinalis, was grown in Medieval monasteries for its medicinal values in treating emotional disorders as well as for its anti-bacterial properties. The healing and calming effects of its smell are not lost on the modern nose or the modern lifestyle. Other “once-bloomers” with enthralling, ecstatic, delicious, rich perfumes are Fantin Latour, Kazanlik, Felicite’ Parmentier, Rosa spinosissima, Belle de Crecy, Desire’ Parmentier, and Ispahan.

Other qualities often left out of modern rose breeding have been cold hardiness and the abilities to tolerate drought, heat, wind and poor soil. Recently, Jamanouchi Pharmaceutical Co. sold Jackson and Perkins to the firm Wassertein and Co. which specializes in leveraged buyout investments. You know these owners are not, and have not been, interested in breeding well-adapted roses for Colorado. And so for years, many roses were bred that were weak and disease-prone plants with beautiful flowers. They required a lot of spraying. Now the trend is toward disease-resistance. Good.

It is very often the “once blooming” roses that are so strong and adaptable to drought, wind, poor soil and neglect. Why is that? Because they are not expending more energies to continue flowering. They can produce their seed, then go into the R&R mode and recover, and focus on photosynthesis. This prepares them better for early freezes; and their vitality makes them more disease-resistant or more disease-tolerant.

Since the repeat flowering genes came originally from the China roses which were not very cold hardy, the modern hybrid tea and floribunda roses can die back considerably in cold climates and cold winters. In contrast, those old-fashioned roses, which have survived a hundred or more years of cultivation through extreme weather patterns, wars and neglect, are usually well adapted to Colorado conditions. If they get an insect or disease problem and you don’t have the time or inclination to do anything about it, they will survive. If you go through a divorce, spend a sabbatical year in Europe, have a baby or are pinned down by your job for a year or more, these roses could still be alive when you return to gardening. Examples of these tough roses are Banshee, Alba Suaveolens, Eglanteria, Madame Plantier, Rosa Mundi, Eddie’s Jewel, Rosa glauca, Cardinal de Richelieu, Maiden’s Blush and Nuits de Young.

And in recent years, rose enthusiasts have found roses with lost identities still thriving in cemeteries, on road sides, and at abandoned homesteads. These “found” roses are proven winners that often were bred in the 19th and 20th century but were dropped from the trade because they did not repeat. Examples of the found roses fill Fairmount Cemetery in Denver and Columbia Cemetery in Boulder. They can be sometimes purchased under such names in double quotes, as “Banshee”, “Dark Red Rambler”, “Fairmount Flouncy Pink”, or “The Yarmouth Rambler”.

In the last 15 years or so, some real progress has been made in rose breeding to select for beautiful flower form and fragrance, as in the roses of David Austin. These may be less tough and less cold hardy than ideal, but still useful. And there has been progress in cold hardiness and disease resistance in the Canadian roses and modern shrub roses, but many of these are lacking in fragrance. Of course, these roses do repeat, and many of them are worthy of growing in our gardens. We can even love them.

However it is unkind and unfair to dismiss the roses, which lack repeat flowering under the label of “once-blooming”. Describing these many wonderful roses by what they lack rather than by what values they possess, is like describing myself as “the old guy with balding hair and a missing tooth.” Instead, we could define Paul’s Himalayan Musk as “The Perfumed Winnebago Blocker”, and Rosa setigera as “The Return Of Spring’s Glory”, “Banshee” as “Fragrant Deer Fencing”, Felicite’ Parmentier as “A Foolish Man’s Winning Apology”, Lawrence Johnston as “The Yellow Wall of Blousy Blossoms”, William Lobb as “An Amazing Piece of Colour”, and the Apothecary’s Rose as “Knits Up the Raveled Sleeve of Care”.

What is it? How bad is it? What do we do about it?

Emerald Ash Borer is an invasive beetle that found its way from China or eastern Asia to the US, stowing away in shipping crates. It was first identified in 2002 and has since spread to 22 states. In September 2013, Emerald Ash Borer (EAB) was discovered in the city of Boulder, which is the first known presence in Colorado. Since then a team has been stripping the bark from samplings of ash trees in Boulder to determine the extent of its spread. It is suspected that EAB has been in Boulder for three to four years.
The beautiful, emerald green beetle is only a half inch long and an eighth inch wide. The adult causes little damage feeding on leaves. It lays eggs in bark crevices starting in the upper branches of ash trees which then hatch mid-May to mid-June. The tiny larvae then bore into the tree and feed on the inner bark. This damages a tree’s capacity to transport water and nutrients and within 2-4 years, the tree will die. Spread of the infestation is at first very slow, but as more and more trees are affected, the spread becomes very rapid. It only harms ash (Fraxinus) trees.
This beetle is responsible for the deaths of tens of millions of ash trees around the US. It is considered by some to be one of the most destructive tree pests ever seen in North America, worse than Dutch Elm Disease. As an exotic invader, the only natural enemies are woodpeckers and certain parasitic insects, but these cannot slow the spread of EAB.
Ash trees have been planted in great numbers in Colorado, because they are tough and tolerant of our difficult conditions. Green Ash, Fraxinus pennsylvanica, is by far the most common ash here. It makes a strong, fairly fast-growing shade tree that tolerates poor soil, some drought, wind and cold. The second most popular is the Autumn Purple Ash, Fraxinus americana, with gorgeous reddish purple fall color. This species is not as tough or well-adapted to Colorado, but has been doing well under cultivation. Right now around 12% of the city trees in Boulder and 14% in Longmont are ash trees, which amounts to about 7,800 trees. In the Denver Metro area there are about a million and a half ash trees. This does not include the trees growing on private property. If even half of these trees die, it will have a profound impact on our shade, temperature (inside buildings at least) and quality of life.
At present there is a quarantine in effect for Boulder County and the city of Erie. Nurseries within these areas are not allowed to sell or move ash trees out of the quarantine area, and are required to keep records of names and addresses of the buyers. Also, all hardwood firewood (regardless of species) cannot be moved outside the quarantine area. Firewood is probably responsible for EAB entry into Colorado, so it is best not to move it very far and to burn or debark it before spring hatching. Ash makes a high quality firewood.
What can be done about this destructive pest? I interviewed two city foresters, three arborists, an Extension entomologist and a director from the CO. Dept of Ag. All of them are waiting for the final word from State Entomologist Whitney Cranshaw who is dancing as fast as he can to learn from the experiences and studies done in the Midwest, and to prepare his report which is expected to be published about the same time as this magazine issue.
In the meantime, here is what I have learned and heard: Everybody agrees that prevention is the best strategy. Once 40% (some say 30%) of a tree is dead from Emerald Ash Borer, it is not wise to invest in treatment. Mitch Yurgert, director of the CO. Dept. of Agriculture Division of Plant Industry, recommended that people begin by determining the value of the ash trees on their property. Ash trees that are unhealthy, broken, growing under wires or not valuable for shade, may not be worth the expense of treating them.
Ken Wicklund, city forester of Longmont said there are some beautiful ash trees in parks and along streets that he will try to save. He said our trees are stressed and may be very vulnerable to EAB. Since Longmont is 12 miles from Boulder, and since the beetle rarely travels more than a half mile to a mile a year, he is not going to start treatments yet. One of the chemical treatments he is looking at is Tree-age because one injection can last 2 or 3 years, which would be more economical.
Steve Pfeiffer, a Boulder arborist who has been doing tree injections for many years, indicated that most of the EAB treatments were injections into the base of the tree, and in his experience, ash trees are especially difficult to treat, because they do not take up the chemicals very rapidly. Our dry soils add to the problem, so watering a tree prior to treatment might be helpful. Pfeiffer likes to use soil injections of nutritional materials and beneficial mycorrhizae and bacteria to help support tree health.
Robert Brudenell, certified arborist, with The Natural Way believes that watering the trees will not only help with injections, but will help keep the trees healthy which will improve the trees’ ability to survive the damage done by the beetle even with treatment. He says EAB will attack even healthy trees and believes that without treatment, ash trees will die. He will be using TreeAzin, a neem derivative, but believes Tree-age is more effective and will be using this too.
Fred Berkelhammer, President of Berkelhammer Tree Experts, is wary of a pesticide over-reaction to the Emerald Ash Borer. He says that as valuable as our trees are, it is the overall health of the earth that we must keep in mind. He is concerned that Merit and other neonicotinoid pesticides that are recommended for EAB are very toxic to bees. He is planning to use TreeAzin (after flowering) because it will not harm bees and because it biodegrades quickly.
Kathleen Alexander, city forester for the city of Boulder, says that the effect of Emerald Ash Borer could be very bad, but that it is good that it was discovered before it had spread very far. Now she and the whole state of Colorado are starting to prepare. Once the state entomologist’s report is completed, she will have a clearer direction for what to do. She said that since this is an invasive species, there are no natural predators and if an ash tree is not treated, it will die. It is best for home-owners to evaluate the worth of their ash trees, and start planting replacement trees for those that will not be treated.
Carol O’Meara, horticultural entomologist with CSU Extension in Boulder County, told me “I’ve gotten to be a pretty good stripper.” She and a group of professionals have been stripping the bark from 766 samples of ash trees to determine how far EAB has spread. They have determined so far that the beetle is within a four mile area. She said that the Emerald Ash Borer is far worse than the Lilac-Ash Borer a pest that has bothered our ash trees for decades. It multiplies very rapidly and the sheer numbers of beetles will girdle and kill a tree within 3 or 4 years. Unfortunately the only way to save a tree is with pesticides. She is unclear whether bees visit ash flowers and might be harmed by the pesticides. She is very impressed by the level of support to Colorado from other states that have experience dealing with this pest.
A USDA report stated that insecticides “…will need to be applied on a regular basis, possibly several times within one growing season, and even then might not completely prevent the EAB from attacking an ash tree.” The most effective insecticides for EAB seem to be tree trunk injections. The reports I read said that one injection of Imidacloprid per year or one injection of Tree-age every two years were recommended. TreeAzin, a bio-pesticide made from Neem, is also injected into the trunk. All give “varying degrees of EAB control”. Soil drenches and soil injections are believed to have “too many unintended consequences.” If treatments are applied as a soil drench under an ash tree, any flowering plants under that tree could carry the poison and harm honey bees and other pollinators. Other pesticides are used as trunk sprays and leaf sprays.
Most of the pesticides registered for EAB are systemic, which means the poison travels through all parts of the tree so it kills the beetle (and anything else) wherever it may be feeding. If the object is to kill, this sounds good, but what about the collateral damage to bees, ladybugs and woodpeckers? And what happens to the poison that falls from the ash trees as pollen, seeds and leaves?
Imidacloprid (in products like Merit, Adonis, CoreTect and Bayer Advanced Shrub and Tree Control) is a neonicotinoid pesticide which acts on the central nervous system of insects “with much lower toxicity to mammals.” Currently it is the most widely used insecticide in the world. The European Food Safety Authority has stated that “neonicotinoids pose an unacceptably high risk to bees.” And their use has been somewhat restricted in Europe. Ladybugs that eat aphids from plants treated with imidacloprid “showed reduced survival and reproduction.” The chemical can last for months or years in the soil where it is “acutely toxic to earthworms” and very toxic to beneficial insects. (from the National Pesticide Information Center). Even if ash flowers are not very attractive to bees, the copious pollen will blow all over and as pollen is nutritious could be eaten by many beings.
One of the most effective and long lasting treatments for EAB is Tree-age. This is the insecticide Emamectin benzoate. “While emamectin benzoate is more toxic to invertebrates (like insects) than to mammals, the underlying mechanism of action…is common to both groups of organisms. Neurotoxicity is clearly the primary and critical effect…including neurodegenerative changes in the brain, spinal cord, peripheral nerves and sensory nerves…changes in body weight…reproductive effects…” It is “…over 600 times more toxic to bees than to the most sensitive mammalian species…” (USDA Forest Service Report).
These are just two of chemical treatments for EAB. Space does not permit further discussion about these chemicals, but it seems there are ample reasons for us to question their use. I was an arborist for 30 years and spent much of my life in trees and caring for trees, but I have to ask: Are our ash trees worth poisoning our environment by treating thousands of trees in our communities? Are these poisons going to get into our water supply? Will they kill our soil life? Will they reduce our beneficial insects causing more pest problems? Will we have to keep ash leaves out of our composts and veggie gardens? Perhaps the bio-pesticide TreeAzin will give adequate control if begun before the beetle damage has gone very far. We need to learn more and really think this through.
In the meantime, as many of those I interviewed suggested, we can start to plant replacement trees. I am including a list of shade trees in a publication done by the Colorado Nursery and Greenhouse Association. Hundreds of trees were rated “A through F”. Here is the list of trees over 30’ that were rated “A”:
Big Tooth Maple; Common Horsechestnut (Buckeye); Western Catalpa; Honeylocusts-Imperial, Shademaster and Skyline; Kentucky Coffeetree; Western Hackberry; Callery Pears: Aristocrat, Cleveland Select, Redspire; Bur Oak; English Oak; Chinkapin Oak; Lindens: Legend, American Sentry, Redmond, Greenspire; Colorado Blue Spruce; Austrian Pine; Southwestern White Pine.
It is also useful to consider whether you actually need a shade tree to replace an ash. Trees on the north and east sides of a building are usually not that necessary for shade. Big trees are more expensive to maintain and take the sun from flowering plants and many grasses. Greater value may be gained by planting smaller ornamental or fruit trees.
Losing thousands of ash trees will have a big impact on our community and will be very painful, but treating thousands of ash trees with nerve toxins could also have a big impact on our community of humans and other beings. Please consider the big picture in your responses to this crisis.

For more information: www.eabcolorado.com or www.emeraldashborer.info
If you suspect Emerald Ash Borer contact 1-866-322-4512

Elderberry is a remarkable shrub or small tree of several species and many forms and colors of foliage, flowers and berries. It has been found in Stone Age and Bronze Age excavations, was one of the sacred trees of the Druids, and has been used as a medicinal herb by early Europeans, native Americans and modern herbalists. However it has not been popular in landscapes until recently when selections have been made for special leaf colors and textures. And now home-food and food-medicine gardeners want elderberries because scientific research has verified herbal lore that elderberries have major health benefits. A recent article in the Wall Street Journal pictured elderberry with seven other berries as “nutritional royalty.”
Elderberry (Sambucus sp.) is a fast-growing shrub with compound leaves, large clusters of ususally white flowers and bunches of small berries. Most grow large, to 10’-12’, and some larger. The wood has a soft, pithy center which means branches are more breakable and trunks may not be long-lived. These qualities have led some authors to the conclusion that elderberry is a big, coarse, sloppy shrub for the wild garden. However, with some proper pruning and selecting the right cultivar for the site, elderberry can offer some outstanding values to gardeners in Colorado.
A Fast Screen: Like roses and raspberries, the pithy center of elderberry’s stem allows it to grow fast. Many people plant poplars and cottonwoods for a fast screen, only to discover they grow far too big and are expensive to maintain. American Elderberry, Sambucus canadensis, grows quickly to 10’-12’ and is not difficult to maintain at that height. I have seen ‘Sutherland Golden’ Elder grow to 12’ where it functions beautifully to screen a neighbor’s high deck, providing complete privacy. If the object is to hide a garage or a parking lot, Sambucus nigra, the European Elder can grow 15’-20’ with dense branching clear to the ground.
Colorful Foliage and Fine Texture: Many yellow forms of elderberry are very effective and beautiful. This is unusual since yellow foliage can look sick or will sunburn in Colorado, or result in a weak plant because of too little chlorophyll. The yellow form of American Elder, S. canadensis ‘Aurea’ is a strong and beautiful, large shrub to 10’. I have seen many examples of this form growing over a 6’ fence and looking attractive from both sides. ‘Sutherland Golden’ Elder is a cutleaf form with beautiful lacy, yellow foliage. The yellow does turn more green in the summer, which is a smart move.
Sambucus nigra, the Black Elder, has very dark green foliage that shows off its white flowers beautifully. There is a cutleaf form, ‘Laciniata’ that has a fine, lacy texture that is very attractive. And there is a new form ‘Black Lace’ with finely cut dark purple foliage that grows 8’-10’ and has pink buds that open to creamy pink flowers. This form is so elegant that it has been used as a cold-tolerant substitute for Japanese Maple. Another form, ‘Madonna’, has strong gold margins on the leaves and only grows 3’-5’ high and wide, and is best grown in some shade.
When growing elder for colorful foliage, it is sometimes recommended to cut the shrub to the ground in early Spring to produce a smaller bush with intensely colored foliage.
Flowers: The flowers of elderberry are very small, but are held in large, dense clusters, sometimes 6”-8” in diameter, flat-topped with S. canadensis and mounding with Sambucus pubens. These flowers are a creamy white, creamy pink and sometimes pink, with a mildly musky fragrance, blooming in May to June. The pink flowers of ‘Thundercloud’ Elderberry arise from red buds and show up beautifully against its chocolate-purple foliage. ‘Black Beauty’ has pink flowers showing up against purple black foliage. These flowers are an important nectar source for bees and butterflies.
Elder flowers are best known for their flavorful and medicinal uses in tea, a floral champagne, fritters, cordials, vinegars, floral waters, ointments, and even as a spring tonic.
Fruit: The berries of the blue to black-fruiting species have a long history of culinary, nutritional and medicinal uses. The berries are only an eighth to a quarter of an inch in diameter, but form large bunches, like grapes, often weighing down the branches. Some people believe that the berries should be cooked before eating (and that is probably wise) to neutralize a slightly toxic effect. Others say fully ripe berries are not at all toxic.
Nutritionally, elderberries are high in potassium, have three times the protein of blueberries, and are rich in vitamin C, calcium, beta-carotene and phosphorus. The berries of Black Elder, Sambucus nigra, are used in many elderberry syrups, used for building the immune system and especially for fighting viruses in flu and laryngitis. American Indian tribes used American Elder in much the same way. Local herbalist and educator, Brigitte Mars, in her book Elder wrote, “It would be difficult to think of any other herb that can serve so many functions and help the body find the balance of health in so many ways.” (She lists 32 different medicinal functions of Elder.)
The fruit is also used in pies, cobblers, and wine. The best culinary elderberries are selections of Sambucus canadensis. ‘Adams’ was selected for large berries on a vigorous, productive shrub. ‘Johns’ is even bigger, producing more fruits and earlier, being especially good for jelly and wine. It is a good pollinator for ‘Adams’. ‘Nova’ is only 6’ high and wide that will set fruit even planted alone. It’s fruit is said to be sweeter. ‘York’ ripens later than ‘Nova’ and is said to be self-fertile, producing the largest berries.
It is difficult to find the final word about what Elders need for pollination. The USDA declares: “While some claim that two or more cultivars are needed for optimal fruit production, a planting of a single cultivar will produce good results.” But my single specimen of Sambucus nigra has been barren for 15 years except when flowers of another plant were shaken over my flowers. The surest answer is: grow two plants of the same species but of different varieties.
We should warn you that it is better to avoid eating the red berries of our native species, Sambucus pubens (aka S. microbotrys and S. racemosa), because of their known toxicity. Whether black or red, elderberries are loved by 120 species of birds that can be attracted with Elder to live in our yards because it is liked for nesting as well as food.
Insecticidal Leaves: The leaves of Elder are toxic and therefore can be used to deter mice and voles. And four handfuls of leaves simmered in a quart of water and strained, can be sprayed to rid plants of aphids and caterpillars. American Indians put elder leaves behind the ears to repel mosquitos.
And More: Elders like water and can live in a wet spot where other shrubs would die, but they can grow on the dry side too. They like composted soil, but are not fussy about pH or fertilizer, as long as they are not bone dry. They are known to be good for compost piles, both providing shade from drying out and also because the root excretions support the composting process. The pithy stems of Elder were burned out by the American Indians to make the stems of their sacred pipes, and native solitary bees like those soft centered stems for nesting sites.
Elderberry can provide the Colorado gardener with so much. To enhance their beauty, prune out the dead, broken and crossing branches. Shape them and give them some water and compost. They in turn will provide screening, attractive foliage and flowers, berries for food and medicine and bring Nature into our environment. It is no wonder that this amazing plant has been revered for thousands of years.

Most of us think of gooseberries as the small, green, sour fruits in a gooseberry pie. I remember, as a kid, thinking that they were only fit for a goose. But now I have had the pleasure of eating several varieties that are delicious, right off the bush, when fully ripe. Europeans have had a couple centuries to cultivate and breed Ribes uva-crispa,(grossularia) which is the European Gooseberry. The European varieties are said to be better tasting than American ones but more prone to disease here in the US, and it is reported that most European yards contain a couple of gooseberry bushes. Americans have a less than positive view of gooseberries, and it is rare to find them in stores and even in farmers markets. One problem is that the native American gooseberries ( Ribes hirtellum being the most common) are mouth-puckering sour. American Indian children of the Omaha tribe invented a game where the two sides competed to see which team had the most players who did not make a face when eating the unripe wild gooseberries. And Americans have not bred improved varieties like the Europeans. Now, however, crosses between the American and the European varieties are resulting in some delicious and disease-resistant new fruits for the home gardener.

Gooseberries and their relatives, the currants, are some of the easiest and most successful plants for the home gardener. They do not have fussy requirements like blueberries, don’t run like raspberries, are productive for 25 years unlike strawberries, produce fruit early and annually and take up far less space than a fruit tree. Herb Gundell, former CSU Extension director and Denver Post gardening editor for 39 years has said of gooseberries and currants that they “…will absolutely require nothing in the way of soil, maintenance or care. They will produce in any kind of condition, even if the weather is the most forbidding, even in years when we have no fruit at all on the trees.” And gooseberries are extremely healthy as they are high in antioxidants, anthocyanins, fiber, potassium, and Vitamins C and A, etc.

Lewis Hill, a famous fruit explorer, nurseryman and garden writer has stated that his favorite pie is a gooseberry pie. And people do make pies from both the ripe and unripe berries. It is also common to use gooseberries in jams, jellies, juices and preserves. Michael Phillips in his recent book The Holistic Orchard gives this receipe for gooseberry butter: “Heat the berries until the skins pop, then force them through a colander, add sugar in equal proportion to the pulp and simmer until thick.” There are many varieties that are delicious right off the bush, with vanilla ice cream, in smoothies and in granola.

Gooseberries grow naturally in cooler climates, so in our hotter western temperatures, it is better to grow them where they get morning sun and shade from the afternoon sun, and perhaps even better in filtered shade, except in the mountains. When temperatures are over 86 degrees F., some varieties will drop their leaves. And the fruit can sunburn especially if exposed by overpruning. It is recommended to mulch deeply around them with 3”-4” of fine wood chip mulch which holds the moisture and keeps the soil cooler. Whereas they can still produce with little care, they will bear more fruit if the soil is amended annually with a dairy cow manure compost or the local chicken manure fertilizer Nature Cycle and maybe some Greensand or banana peels for potassium.

For best production, it is good to prune gooseberries. Thin out the shoots to 9 or 12 and remove canes older than 4 years (they have dark brown bark). Do not cut to the ground as they fruit on wood that is at least one year old. Keep the center open enough to allow for picking, but leave some branching to shade the sun-burn sensitive fruit. Remove growth that touches the ground, and compact leggy growth. Gooseberries start bearing after a year old, but may take 4-5 years to attain full production. While they are self-fertile, planting more than one variety can boost yields.
Some eastern states are still worried about the White Pine Blister Rust that is carried by some Ribes including gooseberries. The ban was lifted in 1960 and the problem is mostly from native wild species; the newer cultivated varieties are said not to spread the disease, which is not a problem in the west.

Did I mention thorns? For full disclosure, you should know that some gooseberries have a few thorns and some have a lot of big thorns. Thorns are some protection against wildlife eating the fruit and browsing the shrubs. Gooseberry bushes can also function as a barrier to control traffic across the yard, and can even keep out dogs and other animals. A couple years ago I discovered that thorny roses at the base of my plum tree kept out the raccoons so this year I am planning to plant gooseberries at the base of my grape arbor to see if that will keep the raccoons from my grapes. By adding a couple of new posts and 2x4s I will use the grapes to give my gooseberries some shade.
Gooseberry varieties I have tried and like are:

Invicta-an English variety that produces very large, white fruit that is very sweet and delicious. The 3’-4’ shrubs are very thorny and very productive. It is resistant to mildew.

Hinnomaki Red-a selection from Finland that is popular with its tart skin and sweet flesh. The fruits are dark red and begin fruiting the first year.

Camanche (Red Jacket)-and English variety that was rated as the best gooseberry at the USDA Cheyenne Horticultural Station, and picked as a Plant Select winner in 2001. It is very hardy and productive with large, red sweet/tart and juicy fruit. This one may need part shade to be healthy and happy.

Others I am planting this year are:

Captivator- a cross between European and American species that is nearly thornless with large, deep pink fruit that is sweet when ripe. It is mildew resistant.

Pixwell-an old variety that is very hardy and even drought resistant. It has fruit that is green turning to pink, that is sweet when ripe and has few thorns. May be better cooked.

Tasti Berry- a cross between a European Black Currant and a gooseberry. In a taste test at Ft. Collins Wholesale nursery, it scored “most delicious”. Sweet and thorny; 3’-4’

On my list to get are:
Black Velvet: sweet, dark red, highly valued
Welcome: good flavor with few thorns
Poorman: very sweet red, very productive, very thorny
Hinnomaki Yellow: aromatic, sweet, yellow-green, with an apricot aftertaste
Jewel: a Polish cultivar with peach-colored fruit, very sweet and productive

Be brave, try a couple gooseberries. On the thorny ones use a leather glove on one hand to hold back the branches while you pick with the other. Kids are said not to like sour fruits but they love sweet/tart gooseberries and currants, especially since they are at kid-height. You will appreciate their success. And their wild self-protective chemistry will support your health and immune system. Since we can’t buy them, let’s grow them. Empower your food garden.

Plants have evolved to time their seed germination, flowering and fruit/seed formation within particular temperature ranges (often regulated by day length). Their distribution geographically is also limited by high and low temperatures. Extreme conditions affect plant performance, survival and reproduction. In 2012, in the Denver-Boulder area, we had record-setting high temperatures: We tied the all-time high of 105 degrees Fahrenheit, and June was the hottest on record. We endured 73 days over 90 degrees and 13 days of 100 degrees or more (in the last 140 years, there have been only 83 days of  100 degree temperatures in the Denver area). And because drought accompanied the heat, 62 of Colorado’s 64 counties were declared crop disaster areas by the US Secretary of Agriculture.

In our own gardens and yards, some plants performed poorly even though we could water them. Tomatoes, for example, will drop blossoms and not set fruit if temperatures are over 90 degrees. In Arizona where temperatures soared above 120 degrees, some plants died even with irrigation. Whether global climate change is a long-term or a short-term cycle, we gardeners are going to have to learn some new tricks.

High heat affects plants in many ways. Seeds may not be able to germinate, fruits or seeds may not form or will drop before maturing. Growth can be stunted, plants can die or be weakened and attract pests and diseases. These observable reactions occur because of the adverse affect high heat has on internal and microscopic activities within the plants. Problems arise in photosynthesis, the formation of hormones, enzymes and defense chemicals; in the intake of water and carbon dioxide, in weakening of the cell membranes etc.

Plants do have natural systems that respond to heat problems. Transpiration is a mechanism in plants to cool themselves by “pumping” water out through the leaves for a kind of swamp-cooler effect. (See Colorado Gardener issue XX  for an article on transpiration) But high heat can cause a plant to exhaust water supplies in this process; or the plant closes its leaf pores (stomata) to prevent water loss, but in so doing reduces the potential for taking in carbon dioxide which is needed for photosynthesis. Plants can also make “heat-shock proteins” which reduce problems with over-heating, but these strategies do take resources away from other plant needs like growth, flowering and fruiting. Some native plant communities have already started shifting northward where temperatures are cooler. And natural selection is undoubtedly giving preference to plants with increased heat and drought tolerance, like ones with deep or wide-spread roots.

But what can we gardeners do to respond to hotter temperatures? And what if these changes last for years and/or become more extreme? A discussion of solutions is frustrated by the fact that the world is investing far more in the problem than in solutions, so at the present, we know little about what to do. Here are some ideas.

We can choose, select and breed plants that show a tolerance for high heat. We can trade success stories with our friends and neighbors and we can learn from communities further south that are already dealing with very high temperatures. Because high heat often goes along with higher water needs and less precipitation, we need to choose, select and breed plants that tolerate drier conditions too. These have to be genuine xeriscape plants for dry, low-humidity Colorado, not xeriscape for Virginia or Iowa.

We will have to develop our skills at soil building to provide nutrition and organic matter that will retain moisture and let rain penetrate to lower depths. Improving soil health also means cultivating the microorganisms that bring water and nutrients to plant roots and that build organic matter and improve soil structure. Supporting the health and vitality of plants is just as important in responding to heat stress as supplying water. Chemical fertilizers, with their strong salts, have more potential for burning plants in hot, dry conditions, so organic fertilizers are preferable.

We can provide conditions that help to keep the soil cooler. Mulching with local wood chips or partially composted bark, or even fine gravel will insulate the soil, keeping it cooler and reducing evaporation. Planting in partial shade can benefit even some sun-loving plants. In 2012 several gardeners reported better success with tomatoes grown in partial shade than in full sun, and many reported failures in growing tomatoes in containers in full sun where the soil gets especially hot. Watering the soil also helps to cool it.

We can also build shading structures to protect plants from heat, especially from the west, which can be particularly hot in the late afternoon. These structures, whether made from lath, shade cloth or the light fabric row covers, need to be high enough to allow good movement of air or they can trap heat.

Other techniques, like foliar feeding plants early in the morning during hot weather, the use of anti-transpirants (like Wilt-Pruf), inoculating with mycorrhizae, early planting in protecting structures, protection from wind, planting next to a rock, and even preconditioning plants under different environmental stresses; all may be somewhat helpful. Whereas it is important for us to seek local solutions in order to be able to have beautiful landscapes and be able to produce good food locally, we cannot ignore the environmental and global effects of practices that waste water, like “fracking” and inefficient irrigation of crops, and that produce greenhouse gases, like the burning of petroleum and the production of chemical fertilizers.

Here is a small list of plants that are known to be more tolerant of heat:

Most of our native plains plants and shrubs including:

Sumacs

Penstemons

Rabbitbrushes

Desert Four O’Clock

Saltbrush

Heterotheca

Artemisias (Sages)

Thelesperma

Gambel Oak

Sulfur Flower (Eriogonums)

Mt. Mahoganies

Blackfoot Daisy

Buffaloberry

Prickly Poppy

Leadplant

Blue Flax

Yuccas

Gaillardia

Cacti

Liatris

SW Natives including

Apache Plume

Red Yuccca-Hersperaloe

Desert Willow-Chilopsis

Fern Bush

Agaves

Cacti

New Mexican Privet

Sphaeralceas-Globe Mallow

Well-Adapted Plants like:

Lilacs Sedums Oregano

Butterfly Bushes

Germanders

Hibiscus

Nanking Cherry

Aethionemas

Paronychia

Blue Velvet Honeysuckle

Salvias

Erodiums

Rose of Sharon

Ruellia

Acantholimons

Boxwoods in shade

Gaura

Plumbago

Junipers

Hollyhock

Dianthus

Many shrub and heirloom Roses

Rosemary

Limonium

(not hybrid teas)

Hymenoxys

Rue

Smoke Tree (Cotinus)

Coreopsis lanceolata

Barberry

Trumpet Vine

Blue Mist Spirea

Silver Lace Vine

Veggies-little is known

Tepary beans

Cherokee Purple Tomato

Swiss Chard

Eggplants

Arkansas Traveler Tomato

Chili Peppers

Cucumbers

Valley Girl Tomato

Purple Calabash Tomato

Melons

Aurora Tomato

New Zealand Spinach

Annuals

Four O’Clocks

Purple Fountain Grass

Cape Aloe (houseplant)

Celosia

Petunias

Dichondra-Silver Falls

Zinnia

Lantana

Caster Bean

Asparagus Vine

Marigold

Gazania

Cleome

Morning  Glory

Cosmos

Amaranth

          In the mile-high, sunny and dry west, silver is more valuable in the garden than gold. Gold and variegated foliage effects may be a gardener’s delight in the moist, shady and cloudy east and northwest, but here many of those leaves burn while silver leaves reflect heat and ultraviolet rays. The silver color of plant leaves is caused by fine hairs, microscopic scales or a waxy substance. These structural adaptations improve the drought tolerance of plants by cooling and by reducing water loss through transpiration.

          At the same time, I have heard silver plants referred to as “social facilitators”, because silver can help harmonize other colors, softening some colors, intensifying others and contrasting and enlivening foliage greens. Here are descriptions of silver plants for the western garden. Some are common, some are hard to find, some require dry conditions or good drainage, but all will help light up a sunny, western garden while reducing the need for water.

          Snow in Summer, Cerastium tomentosa, is common but could be better used. It is very silvery when grown in full sun with little water. The early foliage looks the best, then the flower stems extend and the plant is smothered in 1” white flowers in spring. Then the plant flops and looks sloppy. If it is sheared back immediately to 2”, the clean silvery mat returns. My favorite Cerastium is C. candidissimum. It is a very compact form only half an inch high and 12” wide with very silvery leaves and small white flowers on 2” stems. It also appreciates shearing, and a deep drink after blooming. This is a drought tolerant, elegant gem.

          There are several species of Pussytoes. All are low gray-silver mats with short stalks of furry flowers that thrive in dry shade. Antennaria rosea has pinkish flowers. Antennaria parvifolia has cream-white flowers and is the most drought-tolerant. The A. parvifolia variety ‘McClintock’ is mostly flowerless and therefore works better between flagstones. Pussytoes can look good both in naturalistic and formal settings.

          Of course the Artemisia sages are famous for their silvery, western look. Big Sage, Artemisia tridentata grows into a 6’-8’ coarse shrub with its famous aromatic foliage that freshens the atmosphere after a rain. Artemisia filifolia, Sand Sage, is a native of theBoulderCountyplains. It has very silvery, thread-like leaves on branched 3’-4’ woody stems. The flowers are not significant, but as the flowering stems elongate, they wave in the breezes, dancing with any nearby grasses. Both these natives make attractive backdrops for red or blue penstemons, Russian Sage or Salvias. A popular landscape Artemisia is A. schmidtiana, known as Silver Mound Artemisia which makes an 18” mound. It is famous for its fine-textured silver foliage and its tendency to fall open and look sad in wet, hot conditions. The ‘Silver King’, ‘Silver Queen’ and ‘Valerie Finnis’ selections of the native Artemisia ludoviciana can be dazzling, but they spread in dry ground like mints spread in moist soil. Artemisia ‘PowisCastle’ makes a shrub-like form 30” high and wide with dissected silvery leaves. It rarely flowers, which is better for the foliage form. Cut it back to a foot tall every fall or spring for best appearance. Just because Artemisias are called sages, don’t try to make your turkey stuffing with them; it will taste like turpentine. Instead, use them to make pungent smudges.

          There are three silver tansies that deserve a place in the western garden. Tanacetum niveum, the Snow Daisy, is an 18”-24” tall perennial with fine-textured silver foliage that looks and smells a lot like Feverfew. In late spring, it is covered with masses of 1” white, daisy-like flowers. Once the flowers are faded, quickly dead-head them because they can self-sow very profusely. Deer and rabbits do not eat this plant.

          Plant Select has promoted Partridge Feather, Tanacetum densum. It has silvery, feather-like leaves that form a groundcover 6” high and 2’-3’ in diameter. Yellow, button-like flowers rise on short stems above the foliage. It performs well in hot summers and dry soils, and dies out from wet conditions. Occasional spots die out for unknown reasons, but they recover quickly if you rub out the dead area with a gloved hand.

          Another attractive Tanacetum, T. albipannosum is a newcomer that grows to 18” x18” with silvery feather-like leaves and big white daisies with yellow centers.

          There are several silver Salvias and Plant Select has promoted three of them. Salvia argentea makes a 2’ rosette with huge, woolly silver leaves “…like rhubarb wearing an ermine coat.” The white flowers can be left to form their loose candelabra or removed to keep the foliage looking better. Salvia daghestanica, Platinum Sage, makes a low-growing mat of rosettes that looks good as a xeriscape edging or a compact feature in a dry rock garden. The purple flowers are dramatic against the silver  leaves. It likes sun, good drainage and good air circulation. Salvia  pachyphylla, Mojave Sage, has silvery green foliage that is very aromatic  and semi-evergreen. The form is shrub-like, with woody stems. The flowers are striking with their violet blue against mauve bracts. This Salvia has been difficult for some people to grow. It is very drought- tolerant, and stunning where successful.

          Hieracium lanatum has fuzzy, very silvery 4” leaves with wavy margins. It stays a modest plant, 8” high by 10” wide. The dandelion-like flowers are nickel-sized and bloom on tall thin stems. It has proved very hardy and long-lived for us in a south- facing terraced bed for over 12 years.

          At our nursery, Harlequin’s Gardens, we discovered a silver leafed form of Teucrium in a group we were growing from seed. We are calling it Teucrium cossonii ‘Silverado’. It forms a dense mat about 4”-8” high and 16”-24” wide of very silvery aromatic foliage. The sweet pineapple fragrance is unattractive to deer, rabbits and grasshoppers. In summer it blooms just above the foliage with pink-lavender flowers. The foliage is just as beautiful in winter as in summer.

          Some silvers are almost white. This is the case with Verbascum bombyciferum. The first year, it grows a pretty, innocent rosette that shines with silvery-white down. The second year it sends up 4’-6’ candelabras of silvery-white fur punctuated with soft yellow flowers. These flower stalks sometimes take on fantastic wild shapes. It is a biennial. It’s cousin, Verbascum wiedemannianum, also has white-silver rosettes the first year, but the second year deep purple spikes of flowers shoot up in early spring. This is also a biennial. Verbascums must have two plants to make seeds, and they will make many seedlings which will sport themselves around, where some will have to be weeded and some will put themselves in the most glorious spots.

          There are many silver stars, but Lonicera ‘Kintzley’s Ghost’ shines like cascading silver dollars. This remarkable honeysuckle with small yellow flowers was discovered by plant-enthusiast, Scott Skogerboe, in Ft.Collins. It was picked by Plant Select as a winner. The “silver dollars” are round leaves with the stem growing through the center that turn a brilliant silver-white and light up the 10’-15’ vine until frost.    

It is probably best to stay away from silver leafed trees. Russian Olive is truly a noxious weed in our water ways. Silver Poplar can send up suckers 30’ away and loves to colonize neighborhoods, and even Sea Buckthorn with its orange, edible berries is thorny and suckering. Our native Silver Buffaloberry, Shepherdia argentea, is more like a big shrub to 10’-14’. It is worth growing, but you need both male and female trees to get the good-tasting red fruit. It does have some thorns, but can make a striking specimen if given a little bonsai pruning.

Because silver-leafed plants are mostly adapted to hot, sunny and drier conditions, they are more difficult to site in non-xeriscapes. Ideally we plant all our low-water plants together and our higher water plants together. If you must plant a silver plant that is fussy about good drainage where it will get irrigated more than once a week, put it on a south-facing slope or where it will get late afternoon sun. Besides being drought tolerant, many silver plants have winter color and are resistant to animal feeding because they are woolly or pungent.

Other silver plants worth searching out are: Inula verbascifolia, Sideritis scardica, Anthemis marschalliana, Hymenoxys argentea, Centaurea bella, Stachys inflata, Stachys byzantina (Lamb’s Ears), Artemisia versicolor ‘Sea Foam’, and Oenothera macrocarpa ‘Silver Blade’.

by Mikl Brawner

A newer science that’s not tied to petroleum profits is emerging to challenge the industrial approach to agriculture and gardening. Enormously powerful, politically connected giants like Monsanto, Bayer, and Dupont will continue to make money, but after 60 years of dominance, the “Better Living Through Chemistry” model can no longer hide its fatal flaws. Mountains of evidence now point to the downside of chemical agriculture: poisoning the earth, driving global climate change, causing major health problems, killing pollinators, destroying the life of the soil. The good news is that a more long-range, wholistic view called Biological Agriculture and Gardening is starting to take its place.

This “new” method is based on an entirely different paradigm or model of plant culture. Instead of the bellicose mentality that birthed the pesticide-fungicide-herbicide and chemical fertilizer approach, the biological approach taps the same cooperative relationships that Nature herself has long employed successfully for survival and sustainability. Instead of seeing bacteria as germs, fungi as diseases, and insects and weeds as pests, the biological model sees Nature as brilliantly creative and diverse, and basically good. The scientific truth is that few insects, bacteria and fungi are harmful; most are beneficial or essential to plant development, plant health, and subsequently for human health.

Instead of blaming Nature for symptoms of poor plant health that result from bad management, and instead of looking at soil, plants, and human health as separate, the biological approach sees the soil as a living ecosystem interconnected with the lives of plants – chemically, biologically and systematically.  Whereas the chemical approach regards soil as the dirt that holds the plant up so chemical fertilizers can deliver NPK (nitrogen, phosphorus, potassium) nutrients, the biological view is that soil is actually billions of living beings that have evolved with plants to function as their digestive and immune system.  Long absent from the chemical equation is the vital role of micronutrients which, although not needed in large quantities, are critical in helping plants to produce complete compounds and essential oils that are important for natural defense.

In order to better understand this biological method and the soil science upon which it depends, I attended the Acres USA Conference in Columbus, OH in December. Founded 40 years ago by the late Charles Walters, Acres USA magazine has been an education vehicle for farmers, ranchers, and orchardists who have rejected the chemical method, and who seek practical solutions and products to succeed with a non-toxic, more realistic approach.

I attended talks taught by farmers and consultants to farmers who are applying these ideas to hundreds of acres, so they have to be economically sustainable as well as ecological. If some of these principles sound airy-fairy, know that they are grounded in practical application and science.  Great strides have been made in the last 10-15 years in the study of soil biology and the soil food web. Many of us in horticulture consider it common sense that plants evolved with soil organisms and microorganisms over millions of years. Their natural intelligence to survive has developed a complex system of mutual benefit.

Soil functions as plants’ digestive system by breaking down raw and complex materials, both organic and mineral, into simpler forms that can be absorbed and metabolized by the plants. The mere presence of a nutrient like phosphorus does not mean that it exists in a form plants can use.  Because this digestive process is carried out by diverse populations of soil organisms, the biological method includes introducing naturally occurring soil bacteria and beneficial fungi that have been propagated in a laboratory, and providing organic matter and minerals that support and increase the microorganisms already present in soil.  As they break down materials, beneficial bacteria and beneficial fungi also release various acids, which are by-products of their metabolism. These acids dissolve minerals and chelate them (make them available).

Beneficial fungi known as mycorrhizae function as extensions of a plant’s root system, increasing the absorbing area up to 700 times to bring in more water and nutrients. In exchange, plants are very generous with the nutrients they produce during photosynthesis, sending them out through their roots for their partner fungi.  Some fungi produce antibiotic substances to protect plants from diseases, while others out-compete pathogenic fungi on the leaf surfaces.

These symbiotic relationships profit both the above- and below-ground populations of what can be viewed as a single ecosystem, almost like the diverse organs of a single organism.

John Kempf, a young rising star in the biological movement, referred to the soil as the digestive system of plants. Like other speakers at the Acres conference, John is focused on soil chemistry. He uses various instruments and soil-testing labs to understand specific soils and to measure the effects of various soil treatments. His investigations show clearly that there is a direct relationship between the organic content and mineral balance in the soil and the vitality of the microbial populations. And further, they show that the health of these soil life populations is directly connected to the nutrition and health of the plants, which is directly connected to the nutrition and health of humans and animals eating those plants.

BIOLOGICAL  THINKING

Soil Building Reduces the Need for Pest Management • Insects and plant disease organisms have simple digestive systems that cannot break down complex carbohydrates, proteins, and plant oils. If a plant is sufficiently well-nourished to store complete carbohydrates, it will not be attacked by pathogens like fusarium blight; when plants are healthy enough to store complete proteins, insects like aphids, corn earworm and cabbage looper will no longer be able to eat them; when plants can store complete lipids (plant oils), powdery mildew, late blight and fireblight cease to attack them; and when plants are able to build complex essential oils, they have a high level of tolerance to environmental stresses and cannot be attacked by beetles.

This is not a theory; it is based on field experience. It means pest resistance or immunity can be achieved through nutrition. Plant nutrition depends on a proper balance of nutrients and a strong microbial community to digest the nutrients and make them plant-available.  Over time, soil building could replace or reduce other forms of pest management.

Compost Teas Greatly Increase Soil Microbes • Compost tea is a method for rapidly increasing populations of beneficial soil microorganisms, and for digesting organic fertilizers like fish hydrolase into a more valuable plant food. The process requires a high level of aeration to support the soil microbes, and offers a local source for soil innoculant and plant fertilizer.

Compost & Worm Teas Prevent Plant Damage • Worm casting and compost teas sprayed on the foliage of plants have been found to prevent fungus problems and even some insect damage.

Plants & Soil Are One, Don’t Compete • Plants send as much as 60%-80% of the nutrients they produce during photosynthesis to the community of beneficial bacteria and beneficial fungi in the neighborhood of their root zones. To human thinking, this is “giving away the farm,” but plants and their soil community are so interconnected and interdependent, they do not see themselves as competing or separate. It is how they have adapted to survive.

Plants Communicate Through Fungal Networks • As insects hatch and begin to feed on plants, the plant chemistry changes. A “wound signal” moves into the root zone with the normal nutrient “leakage.” This chemical signal is then carried through the vast network of fungal mycelium to hundreds or thousands of other plants that “read” the signal and begin to change their chemistry to be offensive or even lethal to the insects. This natural defense system works best when there is a strong microbial population, and when plants have enough nutrition to build their defense chemicals.

Microbes R Us • The idea that soil microbes are the digestive system of plants is not unique. Termites can’t digest cellulose in the wood they eat, but bacteria in their guts can. Plant roots of legumes cannot “fix” or capture nitrogen from the air, but the bacteria in their roots can. Animals also have beneficial bacteria and fungi living in our digestive systems, which are essential to our well-being. Interspecies cohabitation is common in nature. Paul Hawkin once said, there are so many microorganisms living in and on our human bodies, we should refer to ourselves as We, not I.

Distinct Bacteria Types in Humans • German researchers recently discovered three separate “families” of bacteria living in human guts. These “enterotypes” are as distinct as blood types and may explain why medicines and nutrients affect people differently.

Compost Benefits are Biological, not Chemical • Chemists have never been able to explain why compost, which is usually less than 1% NPK, has such a strong beneficial effect on plants. The answer is biological, not chemical. Compost feeds the soil life, dynamically increasing the availability of nutrients in the soil, and the microorganisms. New patents for non-toxic biological fungicides and insecticides that can replace petrochemical products are on the rise.

Invest in Long Blooming Flowers for Pest Control • An investment in seeds of flowers that bloom through the summer will provide more pest control (attracting beneficial insects) than the same investment in pesticides.

“Push-Pull” with Repellant and Trap Plants • Push-pull technology developed in Kenya and adopted by 46,000 small farmers, uses biological thinking. Maize is intercropped with repellant plants and surrounded by an attractive trap plant in the border. A destructive pest is “pushed” by the repellant plant and “pulled” by the attractant plant. which together protects the maize.

The system also reduces a prevalent weed, reduces erosion, increases soil organic matter, fixes nitrogen, conserves soil moisture and supports beneficial insects.

Brilliant solutions to problems of survival have been selected by Nature over time. These solutions follow basic principles: life creates conditions that support life; life changes and adapts. Following these principles naturally leads to sustainability and efficiency. Especially now, with the leverage of petroleum becoming less reliable, we can learn to support our farming and gardening with biological solutions.  However, this is still a new science and work needs to be done to learn about and apply it in the most practical, economical, and local ways.

Most of us in Colorado know that Agave is the source of tequilla and Agave sweetener, but fewer have seen it growing here. Even more rare is the sight of Agave in bloom. The Century Plant doesn’t really take 100 years to bloom, but it does seem to take forever. After 13 years, my Agave parryi, whose bold and armed rosette finally achieved 31” in diameter and 16” tall, began this May to push up a bloom stalk. Then it skyrocketed 3”-4” A DAY until it reached eleven and half feet tall with a candelabra  of rich yellow flowers. Eclectic horticulturist Bob Nold says in his book High and Dry, “Their flowering, mostly, is as spectacular a thing as the plant kingdom has invented….”

This spectacle not only attracted visitors like a zoo, but it magnetized an oriole to sup at its cups of nectar, as well as hundreds of bees and wasps. Hummingbirds are supposed to be attracted, though we didn’t see any, as are moths, flies and in some areas, bats. Even after the freshness of the flowers has faded, it is still worth a visit to see.

I asked Panayoti Kelaidis, director of outreach at Denver Botanic Gardens and master horticulturist, if Agave is well-adapted to Colorado conditions. He answered that some varieties do well in the Denver-Metro-Boulder area,including Agave parryi, A.neomexicana and A. havardiana. Other species are possible if established in favorable conditions and in a good year, including Agave lechiguilla, A. polyanthaflora, A. utahensis and A. deserti. Panayoti mentioned that favorable conditions include a rich, gravelly soil with some compost and a gravel mulch in full sun, especially on the south side of a rock. Wet and windy sites should be avoided. Mr. Kelaidis added that there are 6 Agaves in bloom at DBG this year, of three species. Plants grown from seed collected in cold-winter areas are most likely to succeed here.

One might assume that Agaves need no supplemental water, like cacti, but that is not correct. Nold says, in nature, Agaves often get summer monsoon rain in the late summer, and suggests a little summer irrigation. He also mentions that dry clay is OK, but a mulch of leaves or other organic matter is often fatal.
Jim Knopf, Boulder xeriscape mentor and landscape architect, said he has grown several varieties, but none of them has bloomed yet. He believes a hot location is good and that winter snow cover that melts off is beneficial. His research found corroboration for my theory that last winter’s sudden below zero cold snap damaged some plants and may have shocked mine (and others) into blooming in order to procreate.  Mr. Knopf mentioned that he has been growing Agave lechiguilla (commonly called Shin Dagger) for ten years, and has been trying for two years to dig it out. Agaves propagate not only from seed but from “pups” that pop up dangerously from the root with their sharp spine leading the way. For the Agave, this is an important point, because after the long wait, and spectacular bloom, the main rosette will die.

Even without the gorgeous flowers, the evergreen rosette of the Agave makes a wonderful architectural feature in a Colorado garden, especially in winter. And it is fascinating to behold the imprints of the neighboring pads, as the rosette unfolds from the center. This plant is not recommended to grow around young children, but it is a delight and a wonder in the xeriscape garden.
Further information about Agaves can be found in Robert Nold’s book High and Dry. Plants of hardy varieties can be found at Timberline Gardens, Harlequin’s Gardens and Paulino’s.

Plant Select is a 25 year old cooperative program combining the efforts of Denver Botanic Garden, Colorado State University and some members of the local green industry. Their intention is to chose, propagate and promote plants that are well-adapted to Colorado conditions, colorful and are either little known or underutilized. The 2011 choices are a particularly excellent group.
Baby Blue Rabbitbrush, Chrysothamnus (Ericameria) nauseosus var. nauseosus is one of the finest native shrubs for the home garden and has tremendous potential in commercial plantings. Claude Barr, author of Jewels of the Plains, calls this species “the gem of the tribe”. It is a native of Colorado from 5000’-9000’ , and sowed itself on our windblown North Boulder property. Unlike the taller, looser, blue and green rabbitbrushes, Dwarf Blue Rabbitbrush grows to a compact mound only 24” high and 30” wide. The fine textured foliage is silvery blue and can grow quite densely. The golden yellow flowers cover the domed form through the fall, making a show that is not only attractive to humans but collects bees, butterflies and beneficial soldier beetles. It is not browsed by deer or rabbits, but the rabbits do like to hide under them.
This tough beauty loves the sun and needs no water once established. In fact, it is better to water it no more than once a week in order to keep the form tight. It does have a tendency for the thin stems to fall open from the weight of flowers and seeds, so it is best to shear off the flowers, cutting 2”-4” after they have finished blooming.
David Salman of High Country Gardens discovered ‘Blonde Ambition’ grass in New Mexico. This larger selection of the native Blue Grama Grass, Bouteloua gracilis, grows to 30”-36”. The seed heads are a chartreuse color that ages to blonde, and they hold up well in the winter garden. Blue Grama has been given the name “Eye-Lash Grass” because of the dainty horizontal flower/seed heads. ‘Blonde Ambition’ is cold hardy to zone 4 and is tolerant of most soils. It is good for xeriscape gardens, requiring little water, and it is low maintenance, needing only to be cut to 2” high each spring. It loves the sun and looks good with other ornamental grasses and taller dryland perennials.
Amsonia jonesii, the Colorado Desert Blue Star, is a western native perennial that has clusters of blue star flowers at the ends of its 10”-14” stems. It blooms from April to June. The color of these ½” tubular flowers must be variable, because descriptions range from sapphire blue, through powder blue to ivory. The autumn color of the foliage is a clear yellow.
The form is upright and mounding to 12”-15” wide. I am glad to learn that although this plant is long-lived, it is slow to develop, and may take 5 years to become glorious. It is reassuring that my bashful 3 year old specimen may need nothing more than time. Desert Blue Star is said to be attractive to bees, but not to rabbits and deer.
Russian Hawthorn, Crataegus ambigua, has been in Colorado for some time, but is not well known and often difficult to obtain. At our nursery, Harlequin’s Gardens, we have a demonstration garden of mostly native shrubs that has not been watered since 2002. The non-native exception in this unwatered garden is Russian Hawthorn which is perfectly adapted to Colorado conditions. It is usually a dense tree, 12’-15’ high and wide with horizontal branching and a rounded form. It’s white flowers smother the branches in April/May and great quantities of round red fruits follow. These make a wonderful show, are usually not messy and are often eaten by the birds. The fall color is a golden yellow.
Like most Hawthorns, Russian Hawthorn does have thorns, but I have not found them difficult to work around. However it is a good idea to thin crowding branches when they are small, because to extract a branch once it is mature is a very difficult job. This is a wonderful small tree for a screen, a specimen, for a wildlife garden or for a very dry and
windy site up to 8000’.
One of my favorite native penstemons is Grand Mesa Beardtongue, Penstemon mensarum. The color of the 2’-3’ spikes of flowers is a rich cobalt blue that glows May to June. The evergreen leaves form a loose mat. It has been long-lived and reliable in two locations for us, and in one eastern location, it is only watered once a month. Bob Nold, in his indispensible book, Penstemons, suggests that it not be grown too dry.
Like many penstemons, Grand Mesa Beardtongue has more impact in a group, so plant two or three 12”-15” apart, or crush the dried seed capsules in your gloved hand in late summer and press the seeds into the surrounding ground to encourage a colony. Especially in clay soils, it is best to water no more than once a week and to grow it in full sun. It can be grown up to 9500’.
‘Avalanche’ White Sun Daisy is a South African Osteospermum which I have not yet grown because it is a new introduction. The large daisy flowers are bright white with a yellow and black-dotted eye, that are very long blooming from April to late summer. ‘Avalanche’ grows as an evergreen mat 8”-12” high and 10”-15” wide. In the evening, these blooms fold up, revealing the coppery back of the petals. Two earlier Plant Select Osteospermums have not been long-lived for me, but this one is said to be a  superior, longer blooming and longer lived variety. It is reported to grow in dry conditions up to 9000’. It may be better to plant it where it gets winter sun, perhaps with a fine gravel mulch to avoid fungus problems.
A great choice for 2011 Plant Select was Erodium chrysanthum, because it is one tough beauty. It has been in the Harlequin’s Favorites display garden for five years. The silvery green ferny foliage is dense and evergreen, and the five-petalled, geranium-like flowers bloom heavily in spring, then sporadically all summer. The flower color is a sweet pale yellow/cream. Whoever named it “Golden Storksbill” must have been looking at the name “chrysanthum” (meaning “gold”) and not at the flower.
This is a very drought tolerant perennial that is easy to grow and holds up for a long time. It looks delicate and petite, but has a big taproot and can grow from 10” to 24” in diameter and only 6”-8” in height. Erodium chrysanthum excels as a specimen, as a  ground cover, in a group, or along a path. She will make your thumb look green.
‘Avalanche’ White Sun Daisy will have to prove itself to me, but all the others in this year’s Plant Select pick live up to their promotion as being Durable Plants for the Garden.

I used to be prejudiced against grasses because I associated grasses with the American monoculture of Kentucky Bluegrass that we all know as “the lawn”. But after testing many kinds of xeriscape plants for over 20 years I finally realized that most sustainable ecosystems have grasses mixed with the other plants. And I also came to appreciate that grasses are strongly self-replicating and that they can be more easily grown from seed than most perennials, so that installation and maintenance costs could be much less. I still think low-water shrubs and Colorado-adapted perennials have an essential place in a sustainable landscape, but I have been wondering how grasses could fit in. Of course Piet Oudolf and Kurt Bluemel have shown the potential for using grasses in a garden, but their examples look well watered and seem like they would be high maintenance. The prairie model so successful in Wisconsin and the Midwest focuses on tall-grass prairie that is out of place here, and so I have been wondering how grasses could be used in a Colorado-sustainable landscape.

Then John Greenlee, who had written The Encyclopedia of Ornamental Grasses in 1992, came out recently with The American Meadow Garden. This very inspiring book, by a man who has left the lawn far behind, is a banner for what could be a new movement in western landscape design, and an ecological alternative to the archaic and energy-intensive lawn. Instead of clipped, uniform, controlled, fussed-over but abused turf, think naturalistic, rhythmic, sensual, diverse and relaxed; plus habitat for birds, butterflies, bees and beneficial insects.

A meadow does not have to be expansive, it can be an opening between trees, a secret space to lie in and listen to the sounds of life. Obviously the naturalist in me is aroused by the image of the meadow. It could take many forms depending on individual styles and tastes: more tall grasses, more short grasses, a mowed area amongst unmowed grasses, wildflowers mixed with grasses, shrubs, small trees, a path mowed to meander through the meadow, etc.

But before we get too carried away by romantic pictures, we gardeners want to know if the amount of work to build and maintain a meadow is worth it. Greenlee’s  The American Meadow Garden book devotes just 35 pages to how to make a meadow, and little of his experience is in Colorado. The Kentucky Bluegrass lawn has had decades of time to develop the methods, materials and machinery to install and manage that grass system. And the meadow idea is too new to project clearly how much work and energy might really be required. Greenlee says meadows require less maintenance than lawns; Lauren Springer-Ogden thinks there is more maintenance, but worth it. Part of the unknown is how much wildness we and the neighbors will tolerate.

A big question for me is, Which plants would be appropriate for a Colorado meadow? Which grasses, wildflowers, and adapted native and non-native perennials and shrubs would require little water, little fertilizer, and very little or no pest management? In other words, how can we design a human-made ecosystem for the American West that is largely sustainable?

I talked with Lynn Riedel, passionate plant ecologist at Boulder City Open Space and Mt. Parks, to get some ideas about which plants are already growing sustainably in our area. Her suggestions for native low-water grasses that could function in a Colorado meadow are: Sun Sedge (Carex pennsylvanica), Rocky Mt. Bluegrass (Poa agassiziensis), Sporobolus heterolepis and Alkali Sacaton (Sporobolus airoides) as well as Buffalo Grass, Blue Grama and Muhlenbergia montana. Not all of these are  available yet from local sources. And her suggestions for forbs (herbaceous perennial wildflowers that grow naturally with grasses) are: Native Blue Flax (Linum lewisii), Stiff Sunflower (Helianthus rigida), Dwarf Sunflower (Helianthus pumilus), Mt. Harebell (Campanula rotundifolia), Blanket Flower (Gaillardia aristata), Dotted Gayfeather (Liatris punctata), Mexican Hat ( Ratibida columnifera) as well as Fringed Sage (Artemisia frigida), Artemisia ludoviciana, Yellow Paintbrush (Castelleja sessiliflora), Aster macheranthera, various Eriogonums, Heterotheca villosa, Senecio spartioides and Thelesperma megapotamicum.

I also interviewed David Buckner, renowned grassland ecologist and soils expert, about his suggestions for how to create a naturalistic meadow ecology for this part of Colorado. David’s company ESCO applies plant ecology to practical problems of revegetation and restoration. I asked him what percentage of native land below 6000’ is covered with grasses and he said 90%-95%. He added, “In the arid west, grasses are intensely superior in our shallow soils because grasses have a fine and dense root system that is ready to grab any water that falls on them.” And I asked him if it makes sense to mix both cool-season grasses and warm-season grasses, and he answered, “Definitely, from both a biological standpoint and an aesthetic point of view.”

Cool-season grasses like Kentucky Bluegrass and the fescues start growing in early spring and resume growing in the cool fall, but go dormant in the hot summer unless they are watered a lot. Warm season grasses, like Buffalo Grass and Blue Grama, don’t begin to grow until the soil warms to 60 degrees or so, thrive in the summer and go dormant in the fall. So mixing the two types together could mean a longer season of green without the huge summer water bills.

David Buckner’s suggestions for low-water meadow grasses include: Buffalo Grass, Blue Grama, Sideoats Grama, Carex duriuscula, Festuca rubra, Poa compressa, Russian Wild Rye, Green Needle Grass, Alkali sacaton and Sheep Fescue. He also suggested the importance of mowing as a substitute for grazing or burning which will result in a more dense covering of the ground, more biomass and increased biodiversity. This mowing should be done at least once a year in early spring. Aeration and once-a-year fertilizing could substitute for other activities of the grazing animals that evolved with grasses.

Another excellent local resource is Don Hijar, owner and manager of Pawnee Buttes Seed Company in Greeley. He also thinks a mix of warm and cool season grasses would make a better meadow, and he agreed with Buckner that the vigor of grasses declines without mowing, burning or grazing. He said the healthiest ecosystem is a diverse mix of grasses, forbs and shrubs. He thinks meadows could be a good ecological substitute for lawns, but he is concerned that Kentucky Bluegrass might crowd out seeded native grasses if people water too much or mow too low or too often. Customers at our nursery tried out three meadow mixes that Hijar designed for us, so we look forward to their feedback.

My exploration into the potential of a Sustainable Meadow alternative to the lawn, barely scratched the surface of local knowledge and the specifics of how to remove or convert a lawn area and plant and maintain a meadow. It will need years of development, as did the lawn, with appropriate varieties, machinery and methodology. But certain points do stand out:

1) The current lawn of highly water and fertilized Kentucky Bluegrass (or even fescues) is not sustainable because it requires too much water, fertilizers, weed killers, gasoline-powered machinery, etc.

2) Grasses do have sustainable potential in our landscapes. As Lauren Springer-Ogden has said, “Grasses are the most successful plant group on earth; plus grasses are adapted to steppe regions like we have in Colorado because this land used to be shortgrass prairie.” And Gail Haggard of Plants of the Southwest seed company has written: “Grasses build the foundation for life. They bind the earth, preventing water and wind erosion. They are the base of the land food chain….”

3) The search is on for alternatives to the lawn. Besides Greenlee’s book another book was released in 2010: Urban and Suburban Meadows by Catherine Zimmerman. And The Ladybird Johnson Wildflower Center is trialing native grass seed mixes for drought and disease resistance.

4) People are gaining a broader vision of the purposes of landscapes. They are no longer just pretty pictures to be seen, but are appreciated as an environment. Greenlee has said, “A meadow is a habitat for birds, a way to reduce the use of water and herbicides—creating one is giving something back to nature.”

5) A meadow could be an opportunity to express an aesthetic and a view toward nature that is less about tight control than respect for the intelligence and will of nature. Garden writer and grasses expert Rick Darke wrote, “Inviting wildness into our garden doesn’t mean inviting chaos—it means relinquishing sufficient control to allow plants to find their ideal niches and to evolve into real communities sustained by fertile, dynamic relationships

So let’s try some meadows. Take “before and after” photos. Maybe in two years, I will write another article in the Colorado Gardener about Colorado Meadows.

by Mikl Brawner

Plants have many important functions, like making leaves, making flowers and seeds, growing, storing starches in the roots etc, but we humans are usually unaware of the vital function of transpiration.

It is estimated that 98% of a plants energy is used in the work of transpiration. How does this process work? and why is it so essential to a plant?

Water moves from the soil into plant roots, up through the sapwood into the leaves. The water, warmed by the sun, turns into vapor (evaporates), and passes out through thousands of tiny pores (stomata) mostly on the underside of the leaf surface. This is transpiration. It has two main functions: cooling the plant and pumping water and minerals to the leaves for photosynthesis.

Plants need to cool themselves for several reasons. When temperatures are too high, energy systems (metabolic functions) slow, and growth and flowering slows or stops. In extreme heat, plants are severely stressed and can die. Sometimes heat will cause bubbles to form that block the flow of water, leading to dehydration. Transpiration is an evaporative cooling system that brings down the temperature of plants, but since it leads to water loss, it must be accurately regulated. The ingenious system that regulates this function consists of a guard cell on each side of the tiny pores (stomata). When water moves into the guard cells, they swell and arch open; as water moves out, the guard cells relax and close. The guard cells are sensitive to light intensity, temperature, wind, relative humidity and carbon dioxide concentrations inside the leaf.

The stomata (pores) must open to take in carbon dioxide for photosynthesis (especially important on mornings of sunny days). And the more they are open, the more plants transpire and lose water. So watering plants early in the morning will support plant energy, especially on hot summer days.

What causes water to rise up through a plant (sometimes 100 feet or more) against the force of gravity? This is achieved by the pumping action of transpiration, which is another ingenious system. It depends on the tiny (capillary) xylem water channels, the extremely strong cohesive (bonding) properties of water molecules, and a sucking force created when water at the top of the channels evaporates. Like sucking on a soda straw, transpiration causes a negative pressure which lifts the column of water to the leaf surface.

As plants transpire, the soil becomes dryer. Then in summer, if the soil becomes very dry, plants cannot transpire enough to keep cool. In desperation plants may start losing leaves or completely defoliate as a way to keep transpiration from dehydrating the plant. Here in the West, in order to help our plants keep cool and keep them photosynthesizing, we can give them extra water in the hottest, driest months. We can plant wind breaks and trees and shrubs that will offer a little shade, and we can mulch to keep soil moisture from evaporating. Evergreens, especially broadleaf evergreens, are very vulnerable to the West’s intense winter sun. Because they have leaves, they continue to transpire in the winter, and can dehydrate. This is especially true for any evergreen that is planted in the fall, but critical for fall-planted ball-and-burlap evergreen trees. So water evergreens once or twice a month in winter.

Transpiration is an elegant, sustainable natural design that performs its vital functions without electricity, without fossil fuels and without moving parts. It does not pollute or use excessive resources. It actually adds moisture to the atmosphere and contributes to rainfall.

Other interesting facts about Transpiration:

1. A leaf transpires about 90% of the water evaporated from a water surface of the same area—even though the combined area of stomatal pores is only 1-2% of the total leaf area.
2. Transpiration rates are highest in leaves that are stiff with turgor (water pressure). When leaves wilt, they offer less surface area to sun exposure, and thus will transpire less, saving water. Watch a tough, drought-tolerant plant like lilac when temperatures are high for a demonstration of this water-saving strategy.
3. Succulents save water by opening the stomata pores at night to reduce transpiration and to take in carbon dioxide which is stored in their leaves until the next day when they can photosynthesize.
4. Cacti, since they don’t have leaves, only have a few stomata in their green stems and so transpire very little.
5. Many xeric plants have small leaves, silvery reflective leaves, hairy leaves and/or produce essential oils which are all strategies to reduce transpiration by reducing evaporation.
6. In the summer, a large maple tree can transpire 50-60 gallons of water per hour into the atmosphere. This adds to the humidity which in the West helps us to feel more comfortable, is less drying for our skin and reduces bronchial problems in our lungs. It also helps to cool our environment. Where there are large areas of trees, the combined effect of their transpiration can create a super-saturated condition in the clouds, which can result in rain or snow. The Snows of Kilimanjaro have disappeared primarily because deforestation has reduced local transpiration, resulting in less (or no) snowfall.
7. Anti-transpirant products, like Wilt-Pruf, can reduce transpiration by covering the stomata pores, but that also limits photosynthesis. They can be valuable sprayed on evergreens to get them through their first winter in your landscape.

References: Plant Survival by Brian Capon; Reaching for the Sun by John King; Dictionary of Botany-Ed. Elizabeth Tootill

By Mikl Brawner

          “You can join the fight to save the honeybees by planting a pollinator-supporting garden.” This is a recommendation made by a Penn. State Master Gardener program. Is this weird? Not at all. The European Parliament has approved creating bee “recovery zones” across the Continent. These recovery zones will provide bees with nectar and pollen in areas that are free from pesticides. Why is it a big deal that honeybee populations around the world are declining? One reason is that one third of the human diet comes from plants that are pollinated by honeybees. Another reason is that honeybees may be the “canary in the coal mine”; just the first to show that there is a problem that hasn’t yet surfaced in other pollinators and other beings.

          We have been told that the problem is “colony-collapse disorder”, and that this is related to pesticides and stress-induced weaknesses. Besides writing to the EPA and local governments to restrict or ban the use of chemicals that harm bees, what else can we do? We can provide nectar and pollen-producing gardens that support pollinators without poisoning them.

          Some suggestions to help you create pollinator-friendly gardens are: 1) plant patches of the same flowering plant, 4’x4’ is a good size. This will make a visual impact and make it easier for bees to locate. 2) put out water in shallow dishes or bird baths with gravel and sand 3) leave cleanup of the garden until spring to help non-honeybee pollinators overwinter 4) plant natives that have evolved with local native pollinators 5) plant different varieties that bloom from early spring to late fall  6) avoid the use of many hybrid varieties with double flowers that lack pollen and nectar, and 7) do not apply toxic pesticides.

          Here are a few bee-friendly plants that love growing in Colorado:

The Mahonia tribe offer nectar, pollen and support for brood-rearing for bees, as well as a wide variety of forms for the gardener. All are evergreen, well-adapted to Colorado’s soils and climate and tolerant of drought. Their holly-like foliage is thick and waxy, helping them to tolerate wind and even winter sun. Our native Mahonia repens grows to only 8”-16” tall and makes a usually loose groundcover under pines or in filtered shade. Mahonia aquifolium, the Oregon Grape Holly is one of our easiest-to-grow broad-leafed evergreen shrubs. Besides having deep-green Holly-like leaves with purple winter color, it also produces blue berries that are preceded by fragrant yellow flowers in April and May. This 5’ spreading shrub is very tough and drought tolerant, and can grow in sun or shade, clay or gravel, moist or dry, once established. There is a compact variety that only grows to two and half feet high.

          Even the more unusual Desert Mahonias, Mahonia fremontii and M. haematocarpa are well-adapted here and are very popular with bees for their abundant, sweet-scented yellow flowers which can perfume a garden to the delight of gardeners, as well.

          Fruit trees depend on honeybees and other bee species for pollination, and, in turn, provide important support for bees. Apricots, with their very early pink blooms are important for bee brood-rearing, even if they seldom make apricots. At 30’ they are one of the largest and longest-lived of the stone-fruits, and they are drought tolerant. Early this April, my wife, Eve, and I watched a hummingbird feeding ecstatically in a blooming Apricot. Another blooming Apricot was so full of bees you could hear the tree humming form a distance. (Maybe we’ll get some apricots this year.)

          Cherries and plums are also valuable for early nectar and brood-rearing. The wild plum is especially valuable because of its colony-forming habit and strong sweet fragrance which bees find very attractive. Apples and Crab Apples also provide great masses of blooms for bees. Make sure you buy Fireblight-resistant varieties because the bacteria that causes this very damaging disease is spread by bees from flower to flower.

          For summer bloom, the Blue Mist Spirea, Caryopteris x clandonensis, has great appeal to bees, butterflies and gardeners. There are several cultivars ranging from two feet to four feet high and wide. All provide profuse lavender to rich blue flowers that bloom for a long time in mid to late summer. ‘Dark Knight’ is 4’x4’ with gray-green leaves and dark blue flowers, ‘Longwood’ is 2’-3’ high and 3’ wide with bluish-violet flowers and may die to the ground in a cold winter. ‘First Choice’ blooms earlier than the others with dark purple-blue flowers. There are a couple gold-leaved cultivars; one is ‘Worcester Gold’ with lavender-blue flowers and is only 2’ high. Every spring cut them back by one third or more.

          The Blue Mist Spireas are not  true Spireas, but the flowers have a resemblance to Spirea. They are very useful deer-resistant, xeriscape shrubs that can make a good single specimen, can be lined up to make a hedge or massed to simply fill and weed-smother a large area. Beware of their seedlings which can be numerous, but easy to dig in their first year. The beautiful blue flowers in the heat of the summer are a welcome sight and the bees really appreciate them when little else is in bloom.

          People often ask at our nursery for one of those magical plants that expresses its sexuality all season long by blooming continuously. Besides the boring explanation that we must plant different varieties with over-lapping bloom-times, another answer is “catmints.” Catmints provide “continuous” bloom if flowering stems are sheared off when they are nearly spent. Then they will provide nectar and pollen over a very long season. Catmint is not the same as Catnip, Nepeta cataria, which is a self-sustaining plant of weedy habit beloved by cats. The catmints are much better garden plants. In 2007 Nepeta x faassenii (N. racemosa) ‘Walker’s Low’ was named Perennial Plant of the Year for its lovely gray-green foliage and lavender-blue flowers that keep on coming. It has no disease or pest problems, is resistant to both deer and rabbits and is sterile so it doesn’t make a nuisance of itself (like Nepeta mussinii which seeds a lot). It is not, however, very low; it can grow 18”-30” high and wide. Similar to ‘Walker’s Low’ but lower and seeding some is the also beautiful Nepeta x fassinii. “Little Trudy” is a dwarf catmint that was found at Little Valley Nursery in Denver, and was chosen in 2008 for the Plant Select Program. It has silvery foliage with lavender blooms that continue for a long time. ‘Little Trudy’ is only 8”-10” high and 12”-16” wide. ‘Six Hills Giant’ is another popular cultivar that grows 2’-3’ tall and wide, and ‘Souvenir d’ Andre Chaudron’ is a Nepeta siberica variety that is very beautiful, long blooming, grows to 18” and requires moderate water.

          Support the honeybees, and plan for a long season of blooms both for the bees and other pollinators, the beneficial insects and for yourself and the neighbors.

Other good bee plants are:
Veronicas, Thymes, Winter Savories, the Mints, Basil, Lavender, Hyssop, Rosemary, Yarrows, Gaillardias, Asters, Campanulas, Mums, Coreopsis, Erigerons, Bee Balm, Dandelion, Sumac, Sand Cherry, Mock Orange, Maples, Redbud, Lilacs, Serviceberries, Cotoneasters, Hawthorns, Willows, Tomatoes, Peppers, Beans, Corn, Cucumbers, Melons

THIS WEEK: 3 Great Classes

June 12, Saturday 1:30pm: Opportunities and Tricks of Xeriscape with Mikl Brawner There are advantages to gardening with less water, and tricks that will improve your success. Mikl’s xeriscape experience of over 20 years has taught him tricks that will cost you a lot less than it cost him. $15

June 13, Sunday 10am: Backyard Beekeeping with Julie Finley. Learn honeybee culture and the plants that support them. Visit our Top Bar hives to learn a great system for natural and small scale beekeeping. Julie buzzes with 14 years experience.She’s a honey $10

 June 13, Sunday 1:30pm: Top 40 Fragrant Roses with Eve Brawner: A Nose-on Class. The enchanting fragrances of roses have been lost in many modern varieties. Eve will share her long experience searching out the truly fragrant varieties, heirloom & modern  $10

GARDENING WITHOUT CHEMICALS

          How can we deal with all the bugs and diseases without using toxic poisons, and how can our gardens really produce without high-powered chemical fertilizers? Many people wanting to garden sustainably are asking these questions. And it is not easy to find the answers, partly because the answers are not simple. I want to admit this up front, but don’t be scared off, because it’s not that hard to garden sustainably once you get the hang of it. However you must know that you can’t just exchange a slam-bam chemical approach for a slam-bam sustainable approach.

          I started investigating this whole subject 35 years ago when I took over the management of a small apple orchard in Iowa. I attended a  Fruit Growers’ Assn. Conference held at the prestigious Iowa State University Agriculture School. It quickly became clear that the professors were acting as agents for the pesticide and chemical fertilizer companies whose salesmen filled the trade show. I was told there are two crops nobody can grow without lots of chemicals: apples and cotton. And they scoffed at an old-timer who told the group that he used geese to remove weeds instead of herbicides. The experience convinced me that I could not trust the university professors’ recommendations. That was when I took the organic road. Later I learned that most land grant universities were subsidized by chemical companies to test their products.

          So the first lesson for us on the subject of gardening without chemicals is: Don’t believe the people telling you that you can’t garden without chemicals, because most of them have something to gain by saying so. This was radical thinking in 1975. Now you may be wondering why make a point of something that is so obvious.

          This historical anecdote is valuable because it shows where we are coming from, and the forces that still influence us, though now they may be green-washed with clever names and slogans, using terms like “green” and “organic” when they have only added a few organic items to their chemical line. My point is: no matter what products or services are called, get the complete list of ingredients or products, especially if a professional is going to spray or apply something on your property. It may not be lethal to adults, but is it hazardous to infants, dogs, cats, bees, fish, frogs, beneficial insects or soil microorganisms?

          The truly sustainable products and companies will take the whole eco-system into consideration, and will talk more about supporting life that destroying life, more about balancing an eco-system rather than about killing an enemy, and more about teaching you a method than selling you a silver bullet.

          I admit, there is something very satisfying (to the ego) about spraying some bugs that are devouring our tomatoes and watching them drop dead at our feet, or sprinkling some granules on the lawn and seeing it bright green, thick and tall only a week later. Wow! Aren’t these crowd pleasers? The problem is, our instant gratification has been coming at a high price to our environment, because of the not-so-instant and often hidden consequences. Pesticides are designed to kill, but they don’t know when to stop killing. Quick-green-up chemical fertilizers that are not completely absorbed by the plants flow into our ground water, create dead zones in our seas, and change our atmosphere. On top of these effects is the tremendous pollution released in the manufacturing of these products.

          So what are the alternatives? I have been asking that question, researching the answers and testing them in my gardens and nursery for 35 years. Sustainability has recently reached a new level with new products and research surfacing every year, and it is hard to keep up with all the new developments. It is obvious, though, that we are now getting a clearer view of the organic path, and that we are far better equipped to garden organically than ever before. In addition, the word is out that organic gardening can not only give us a cleaner world and healthier food, but it can also significantly support the reduction of greenhouse gases.

          One of the most important themes of gardening organically and sustainably is: strong and healthy plants have few pests, and strong and healthy plants come from strong and healthy soil. As Wendell Berry, farmer and eloquent spokesman for sustainable agriculture, has explained: if a soil is deficient in a healthy soil life, the plants growing on that soil will also be deficient, and the animals and humans eating those plants will also be deficient. This is why I say that we cannot just switch from a chemical silver bullet to an organic silver bullet. A significant part of any sustainable solution is understanding the cyclical nature of nutrient sharing. We humans must do our share to give, not just take, from the nutrient cycle.

          The short answer to how to have a healthy soil life is to follow Naure’s example of returning organic matter to the soil every year, by mulching and adding composts and organic fertilizers. This process may take more time and care, like preparing a home-cooked meal from scratch, whereas using chemical fertilizers is like dining at the 7-11 on high fructose corn syrup, processed food and other imitation food stuffs. Chemical fertilizers are derived from petroleum. They are known to burn microorganisms and have been shown to require as much as ten times more water to prevent burning of plants. In addition their manufacture and use releases nitrous oxide, the most ozone-depleting substance made by man, and 300 times more potent as a greenhouse gas than carbon dioxide.

There are now many locally-produced sources of good organic soil amendments and fertilizers which are good for the plants, and responsible for far less greenhouse gas emissions.

Another important theme in organic/sustainable gardening is using plants that are well-adapted to our area. Sure, if you just love astilbe or rhododendrons, you can make a special area for them. But the majority of plants for the Front Range of Colorado should be water-thrifty and tolerant of alkaline soils, hot summers, cold winters, strong wind and rapidly changing conditions. They should also be resistant to our common pest and disease problems. Why plant a Jonathan apple, for example, that will be weakened by fireblight, require spraying and/or higher maintenance, when there are apple varieties resistant to fireblight. And we should focus on ornamentals, vegetables and fruits that flower or ripen in our shorter growing season. I would love to grow Maximillian Sunflower, but it doesn’t bloom until October and is often smashed by snow. And I would love to grow a Braeburn apple, but it usually won’t mature within our growing season. Natives, of course, are well-adapted to our conditions, but so are many other plants.

Then there is the theme of right-plant-in-the-right-place. A Russian Sage is bullet-proof, right? Not if you plant it in the shade. And iceplants that love sun may melt if they get too much hot late afternoon sun. So plants need to be given conditions specific to their natures or they will be stressed and diseased, attract pests, look bad or die. This is part of the challenge and fun of gardening: we have to get to know our plants and nurture them in the right way, even if that means reducing the water or fertilizer.

Another theme of organic/sustainable gardening is monitoring pests and diseases and evaluating them. Although it is another job to learn to recognize different insects and diseases, it is also part of the magic of creation which we get to tune into. When we learn to tell the difference between a rose slug and a ladybug larva, it can help us to see when nothing needs to be done, because Nature is taking care of the pests. And we can learn to not panic at the mere presence of a pest; we can look to see if the damage level merits intervention. I purposely leave small populations of pests in my garden to attract and feed beneficial insects.

Controlling pests brings up another organic theme which is: If damage levels are too high to be tolerated, use the least toxic, least invasive method that will support you plants. Some diseases can be eliminated by reducing water or by watering in the morning so the soil can dry before nightfall when humidity can condense on leaves. Some insects can be blasted off with a strong stream of water. Some sucking insects can be discouraged by spraying the leaves with seaweed (kelp) which toughens the leaf surface. Home-made (and commercial) sprays made from chili powder, garlic, eucalyptus etc can repel insects.

When pests need to be killed, my favorite method is horticultural oil. It is a mechanical pesticide, meaning that it is not at all poisonous and acts by coating soft-bodied insects with oil and suffocating them. It must be sprayed on the pest to be effective. I like this control because it has no effect on beneficial insects, bees, birds or soil organisms. I like the Pure Spray brand because it can be sprayed on the leaves without any burning. Horticultural oils cannot be sprayed over water with fish.

Insecticidal soaps are also popular because of their very low toxicity and negligible environmental impact. They act by dessication and must be sprayed directly on the pest to be effective. Both insecticidal oils and soaps may have to be reapplied to reduce larger populations and egg hatches. There are many Neem products that vary greatly in their strength. Neem works as an anti-feedant and disrupts insect development. It can be effective also against powdery mildew. Neem is an active ingredient in my toothpaste, so it has a very low toxicity when applied as directed.

Although it breaks down very quickly, I don’t recommend using Pyrethrum since even the powdered flowers of the Pyrethrum daisy are quite toxic, effecting beneficial insects and even cats. The synthetic pyrethrins and pyrethroids are more potent and longer lasting and therefore more dangerous. There are so many “soft pesticides” on the market that I can’t talk about all of them, but I am wary of Spinosad which effects the nervous system of insects and may harm bees.

Among the fungicides, the only one I recommend is Green Cure which is a potassium bicarbonate product, very similar to baking soda and not harmful to beneficial fungi in the soil. It is very effective, though the appearance may not change for a while. Even baking soda reduces some fungus problems, as does horticultural oil. Many fungus problems can be controlled culturally by reducing water, watering in the morning, using drip irrigation instead of overhead watering, improving air circulation or light exposure, aerating the soil mechanically or adding soil amendments.

One of the best pest controls is a diverse population of plants that support beneficial insects. It is especially good to grow plants with clusters of small flowers that provide nectar. Stuart Hill, a professor at McGill University, once said, “An investment in seeds of plants that will flower through the summer will give more pest control than that same investment in pesticides.”

The least toxic herbicides are horticultural vinegar, certain soaps and clove oil products. These are all most effective on annual weeds sprayed on hot, sunny days. Some perennial weeds can be controlled when used on small weeds or with repeated applications. Boiling water works where no valuable plants are nearby, as in between flagstones. Flaming by scorching the leaves is effective, but uses propane. Hand weeding is most effective when done before weeds get big enough to feed their roots.

Roundup and the glyphosates are NOT nontoxic. It may be unrealistic to say “never use them”, but almost never use them. Problems with cracking bark have been linked to the use of glyphosates near woody plants, and Roundup has been shown to be extremely lethal to amphibians like toads and frogs. In addition between 1984 and 1990, glyphosate was the third most reported cause of pesticide illness among agricultural workers; and the most reported cause by landscape workers. (See the sidebar)

Last on my list of themes of organic and sustainable gardening is “a naturalistic attitude,” as opposed to a “control freak” attitude. Learn to accept a certain level of damage. Trying to dominate Nature with complete control is unrealistic and unfriendly. Being OK with 10%-20% damage will make your life much more relaxed and require less time and money spent on maintenance. From a little distance, it may not even be noticeable. It is important to understand that only a small percentage of insects and fungi are pests and many are beneficial. It is also good to recognize that gardens with bugs support birds and beneficial insects.

Our reward for using a non-toxic approach to gardening are gardens and landscapes we are not afraid to touch and eat and let the children play in. Our soils and plants are genuinely healthier and our food is more nutritious. We support a world environment that is healthier and more diverse, with fewer greenhouse gases and a more peaceful people. Instead of contributing to an environmental global crisis, organic gardening and farming are becoming part of the healing of our planet.

SIDEBAR:

 Roundup and Glyphosates

Since it was introduced in 1974 by Monsanto, it has been applied to more land area than any other active ingredient. This may be due to the advertised perception that it is essentially harmless since it biodegrades so quickly. It is my understanding that the safety of Roundup was based on tests performed on glyphosate alone, and it is coming to light that other ingredients added to these herbicides are responsible for some of the dangerous side-effects. Hannah Mathers, Ohio State University nursery and landscape specialist, tested many glyphosate products and discovered that it is the surfactants, known as “adjuvant loads” that cause bark splitting of woody plants if sprayed within 30’ of their trunks. This can be a serious problem since it takes years to break down the chemical once it is taken up by the shrub or tree. Other problems associated with the use of glyphosate herbicides include witch’s broom, stunting, growth problems, dead branches, and death. Ms. Mathers recommends using glyphosate products that do not contain the adjuvant load: Backdraft, Campaign, Expert, Extreme, Fallowmaster, Fallow Star, Fieldmaster, Glypro, Landmaster BW, Land Star, ReadyMaster Atz, Rodeo, Roundup Custom, and RU SoluGran.

In addition the Weed Science Society of America has warned that overuse of glyphosate has led to resistance in nine species of weeds, requiring higher doses for control or lacking any control. Their conclusion is that we need to find other methods of control.

And as mentioned in the main article, between 1984 and 1990 glyphosate use was the most commonly reported cause of pesticide illness among landscape workers and the third most common cause among agricultural workers.

Other resources:

Pesticide Action Network  www.panna.org

Audubon Society guide to home pesticides: www.but.ly/pesticidechart

Beyond Pesticides: www.bit.ly/lawncare

(Also, Jane, the data about pesticide illnesses in my last paragraph came from a Heritage Rose Soc newsletter with no sources)