My Garden and the Bugs That Share It My Garden and the Bugs That Share ItBy J. "Gus" Guzinski(Reprinted from the Daylily Journal by permission of the author.)
My personal approach to pest control is based on the desire to keep my garden healthy--healthy for the plants, healthy for my family and healthy for the sundry living things that share the garden with me. I also don't want this to be more work than necessary.
I decided that my pesticide usage would be minimal. I am not convinced that heavy use of pesticides makes for less work for a gardener. It might or might not produce more attractive flowers but it can have other consequences over time. I plan to garden for many years and hope to watch my garden get better every year. If I undertook a massive spraying program and had perfect flowers one year, I would then spent the rest of my life trying to match past perfection. My chemical usage and the work that entails would probably increase year after year.
The Chemical HabitSome time ago I received a letter from a woman who was seeking advice on what to do next for her garden. She had sprayed her daylilies--she thought they had spider mites--and then realized that she had measured the unnamed chemical in tablespoons and not teaspoons. When her daylilies started to look poorly, she then mixed several different chemicals that she had stored in her garage, a little was in each bottle, and sprayed again. At this point, her daylilies were clearly dying. She took a leaf to the Cooperative Extension Service and was told that her daylilies had a fungus. She wanted to know what to do.I confess that my reply was more honest than kind. My advice was to cease spraying and allow her plants and her soil to recover. Some daylilies would survive and, after the garden healed the worst damage, she could start again. The fungus that was found was probably one of the kind that grow on dead leaves. Dead plants are supposed to rot and she had done a pretty good job at killing her daylilies.
This story illustrates the importance of knowing what you are doing when you use chemical sprays. I advise everyone who uses chemical pesticides to take a course from your local extension service to learn proper safety, both for plants and for people. An acquaintance of mine has medical problems which he believes were caused or exacerbated by inhaling pesticides. In the past, he had become violently ill after using them. Although this is not proof of the harm of pesticides, an inexpensive respirator would be so much safer.
That you can easily purchase a pesticide does not mean it is safe. In a garden center, I looked through the section for insecticides for indoor use to discover that one of them had an ingredient that could not be sprayed outdoors legally. I find it difficult to believe that this insecticide should be sprayed inside an inclosed space where you cannot help but inhale it.
It is not necessarily true that easily obtainable pesticides are less dangerous than "restricted" pesticides. For example, Malathion is also available as a restricted pesticide; the only difference from the household product is the size of the container. And it is important to remember that many pesticides are toxic. Some such as Cygon-2E are nerve toxins in humans. Others such as Sevin are known carcinogens in rats. I suppose that one obviously should not spray them on rats.
Using Only EnoughPesticide usage is also one of degree. There are those who spray on a routine basis with the strongest pesticides they can legally buy. This is trying to keep a garden free of living things other than plants. It is an endless task but a gardener's personal choice. I am leery of a garden in which nothing from the animal kingdom is alive. I am a member of that kingdom.
There are those who spray "when necessary." One of the most important things to know is what you are trying to kill. With daylilies everything is blamed on thrips, whether or not thrips are present. It is important to determine the cause of the problem; it might not be thrips. Many an innocent ladybug and assassin bug has been murdered while trying to feed on pests damaging the flowers in a garden.
There are those who never spray with anything. They are braver than I am, or more clever, or simply better gardeners.
Having decided to minimize my use of chemical sprays, I needed to determine when and what to use. Not all chemicals are safe for daylilies. Some damage daylilies and some have not been tested on daylilies. It has been published repeatedly in the Journal that Kelthane( checkthis) and other insecticides with the same active ingredient damage daylilies. You should only use pesticides specifically labeled for daylilies. This data is on the label. In fact, it is against the law to use a pesticide on a plant for which it is not labeled. You may be subject to fines for violation of federal law.
This is true for herbicides as well as insecticides. If you examine an herbicide package containing trifluralin as the active ingredient, you will see that daylilies are absent from the list of plants for which it is approved. Preen(R) and Treflan(R) contain this compound. Surflan(R) and Eptam(R) do list daylilies as approved plants on the label. I assume this difference in the labels in purposeful. As with any pesticide, it is necessary to use the chemical following directions and to check the results. Cultivars differ in sensitivity to chemicals. Even a chemical like 2,4-D will only harm SOME daylily cultivars. The roadside fulva will not even notice a treatment with 2,4-D.
Integrated Pest ManagementWhen determining a course of action, you first need to determine the source of the problem. The possible number of insects that may be in a garden is immense; only a few cause enough damage to be noticed. One of the simplest ways to identify pests is to use a sticky card to collect bugs in your garden. It is possible to buy a brochure to identify bugs stuck on sticky cards. IPM Laboratories, Inc., P. O. Box 300, Locke, NY 13092-0300, (315) 497-2063 is one source.When I choose to use a chemical spray, I choose the mildest one that will slow down the epidemic. Eliminating a pest is impossible--my chemical usage is meant to be a short term solution until I can find a better one. Biological control is often possible. This approach may mean more work in the beginning but I believe less work in the long run. One must identify the problem and then find the solution. The damage must be attributed to a specific cause and then rectified.
Integrated pest management is a term that is gaining popularity. This does not preclude using sprays although a spray is chosen with minimal impact outside of the knocking down a specific pest. It is a temporary solution. Repeated spraying is proof that the garden's ecology is still imbalanced. Success with integrated pest management is based upon getting to know your garden, both the flowers and the other living things in it.
Introducing a natural predators in you garden is often a permanent solution to a pest problem. A large population of a pest is a banquet for the predator that can find it.
It is also important to provide a suitable environment for the predators in your garden and to attract new ones. Many insect predators need an alternate food source, such as tiny flowers rich in nectar. As an example, I find that annual rudbeckias with green centers are a favorite food source of the adult soldier beetle whose larvae feed on grasshopper eggs. These predators are very common in a garden with many daisy type flowers. Maybe the grasshopper population will come into balance with no action on my part, other than growing more rudbeckias. I certainly hope so. Major damage is done to seedlings. Baby grasshoppers cut them short in early spring and then seem to move on to other plants. In late summer, grasshoppers are back chewing on a few flowers. They have also eaten holes into seed pods. Of course, I set too many pods anyway and can afford to lose a few.
Aphids and spider mite are examples of pests that can be controlled (no pest can be eliminated.) The less toxic chemical sprays such as Malathion are quite effective. However, the completely non-toxic sprays based on soap with citrus oils also work. It is important to use them as soon as you see signs of the insects because damage to small buds will give damaged flowers weeks later. These tiny insects have a large number of natural predators; some are commercially available. IPM Laboratories, Inc. sells a large variety of them including predators for thrips. They may seem expensive but this must be compared to the cost of long-term pesticide usage. The best predators are those that become permanent residents of your garden. I used to see spider mite webs on many daylily scapes. Bud damage was severe several years ago when the garden was new. It is less so with every passing year. I don't know if this is a result of my one-time purchase of mite predators or build up of predators naturally present in this area.
It takes time to get a garden into balance. We built our house several years ago, in the woods. The first section of the garden was devoured by slugs and other pests the first year. It seemed that I would get wave after wave of new pests. This should not have been surprising. My house and garden upset the balance that had developed in the previous forty years as the poor farm land became woods. My garden was a free lunch, a picnic spread of new delicacies. As the garden has become established, I see more variety in insect life and fewer population explosions of a single insect.
Slugs are no longer a problem, even on hosta. I see slugs but not enough to be a problem; my hosta do not look worse than those grown by people who maintain a spray routine. I attribute this to frogs and toads. There used to be a lot of slug damage in my garden. Now I rarely see gray slugs although brown slugs are moderately abundant. Control was achieved by increasing the frog and toad population--I put in a pond. Now, I have thousands of tadpoles every spring. Such a pond cannot have goldfish or koi because they will eat tadpoles. Mosquito larvae do not seem to be a problem; I suppose that tadpoles eat them. One of the important things to remember about frogs and toads is that they are sensitive to most pesticides. They readily absorb them through the skin. Frogs and toads do have their bad points. At night the amphibian serenade outside my bedroom window is louder than a city street.
The metaldehyde type slug baits are not very effective. They do not kill slugs outright but only stun them. Paralyzed slugs die only if the following day is sunny. If they recover before the sun dries them out, they crawl back in the shade. For slug control, I also suggest throwing spent flowers around the clump so that the slugs eat the spent flowers instead of making the long climb up the scapes to reach the new flowers. Give them free food on the ground and they won't search any higher. As a last resort for preventing slug damage, grow only tall daylilies. Slugs won't do much damage to flowers on three or four foot tall scapes.
Other InvadersEarwigs are alien invaders, they are not native to the States and have few predators. I am not certain that they are a problem in my garden. Certainly they are disgusting when they drop out of a flower arrangement onto the table when you are eating dinner. I see them in daylilies but do not normally see any damage on a flower that may contain several of them. They seem to be drinking nectar. Their heads are down in the throat with their distinctive two-prong behinds sticking out. I have been told that they chew flowers but I wonder if this damage is done by something else that is present at the same time. It is also possible that I have a harmless species of earwig with no appetite for daylily flowers.Some pests are just too cute. Katydids aren't attractive as adults, but as babies they are charming, gangly critters. The young are not a problem; they crawl harmless around the flowers and seem to live on pollen until they get old enough to grow wings. At that point they can be as voracious as grasshoppers. However, I decided just to live with them. Their population is not increasing. I believe that some insect damage should always be acceptable in a garden. My goal is to have a healthy collection of insects in a healthy garden. A garden in which nothing but plants can live is not my idea of a healthy garden. If I sprayed for katydids, what else would I kill? What would move in to replace them?
Although Japanese beetles are well established where we live in Michigan, it took a couple of years for them to find my garden. I hope the population has reached its peak. It is fortunate that the Japanese beetle does not have a fondness for daylilies. I squash a few when I see them on pale yellow daylilies but do not do much to cut down on the numbers of them. I only try to relocate them. I keep them out of my seedling bed by growing Virginia creeper on the fence around the bed. This plant is much preferred by the beetles, as is sassafras. I also suggest planting scented roses on the perimeter of your garden to attract the beetles away from the plants you want to enjoy. The yellow traps do catch a lot of Japanese beetles but they attract even more. The most effective way to use traps is to give them as presents to your neighbors to lure the beetles out of your garden. The problem with soil drenches, such as Diazinon(R), that are used to kill beetle grubs is that they are even more poisonous to earthworms. This is why they are effective for moles. A soil drench to discourage moles can only be effective if it kills worms--the favorite food of moles. This is too high a price for me to pay to knock down Japanese beetles or discourage moles. Others may choose to pay the price. I make one exception and do spray the Japanese beetles that land on a small Stewartia tree. It would not survive being leafless for a month of every summer. Every second or third day, I use a pyrethrum spray on the beetles that collect on the leaves.
Personal ChoicesYour garden requires many personal decisions. How big a part of the ecology of your garden will you be? You are the biggest predator. You may also be the biggest source of destruction. What to spray? how much to spray? how safely to do it?--these are up to you.Your choices affect your plants, your insects, your family and your visitors. I want to make a plea for garden etiquette with sprays. It is not polite to spray the morning of a scheduled visit. You may not mind inhaling fresh pesticides but many people do. I once turned down a tray of home-made goodies when visiting a garden because of the obvious pesticide residue on the plants that I may have touched. I just wouldn't eat in that garden.
A friend of mine said he did not like to use pesticides because they smell bad. You only smell what you inhale. Think about that. They should smell bad to let you know that they are there. I would prefer that disgusting aromas be added to all pesticides. The ideal situation would be that the aroma would persist until it was safe to re-enter the garden.
I use fewer pesticide sprays than I did years ago. I am not opposed to their occasional use but, for me, they are no longer worth the work and cost involved. Yes, my approach to pest control is still work. It takes effort to keep track of what is happening in the garden. I spend a lot of time in my garden examining the miniature wildlife in it. Somehow, I don't seem to mind the time and effort I spend there. It is such a healthy place, teaming with life.
Dr. Guzinski is a chemist working for a spice company. This may explain his caution with the use of pesticides and other chemicals. As an amateur hybridizer, he is working for earlier bloom in daylilies in his climate. He has also been analyzing the carotenoid pigments in daylily flowers using the equipment of the company for which he works. You can reach him at: DrBeaugus@aol.com
- Barry Glick
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