Practice No. 16. Dealing with Consequences
When rules of nature are violated, there are consequences. It doesn't matter who or what violates the rules, there are consequences even if we don't recognize them as such. If we don't see populations of microorganisms nuked by synthetic, or organic chemistry, that doesn't mean they're not wiped out. An easy way to tell if your landscape is subject to unwanted consequences is in how healthy it is. If plants are living, growing, blooming and producing in harmony with nature, free of pests and disease, you enjoy the consequence of successful gardening. If not, then it's time to examine one's gardening practices to find out where the problem began, then correct and re-mediate.
In this series, Creating Organic Landscapes, I wrote a lot about the importance of a thriving soil ecology filled with a diverse amount of beneficial microbes working 24/7 with and for plants. The Education Issue 2012, latest issue of Colorado Gardener, contains an article about microbial life that portrays a good deal more eloquently than I've explained, the symbiotic relationship and importance of the biological side of gardening, aptly titled, “Biological Farming and Gardening” by Mikl Brawner. The Colorado Gardener publishes both a hard copy and free online version.
The final practice is also the sixth principle of organic gardening: Consider troublesome insects and diseases as symptoms of a violation of one of the first five principles (of organic gardening). Soil, soil life and plants are interconnected and interdependent – ill health, insect infestations and disease flag us that something is out of balance, out of harmony.
There is a recognized method to managing problems in the landscape -- Integrated Pest Management, (IPM), or as I like to refer to it, Integrated Problem Management. IPM is a four-step system of managing landscape problems by using the methods that are the least harmful to the environment first. Through observation of the landscape, recognizing and assessing any problem, monitoring its effects and evaluating the amount of damage, gardeners are able to more effectively manage problems with minimal environmental harm. The fourth step, management of the problem, emphasizes using the least harmful management method before moving to the next level. The four management techniques or strategies are cultural, mechanical/physical, biological and chemical.
Pest insects first feast on unhealthy plants. The best management tool is to have healthy plants. Stress prevention of plants is your first line of defense in preventing pathogen infection and pest infestation. Pathogens can be difficult to manage and damaging to the plant once present. Weed infestations are best caught early and managed by proper cultural practices.
Observation. Frequent visual inspection of your plants and landscape is the most important step. It is much easier to manage a problem in the early stages, whether it is a weed seedling or beginning of a disease or pest infestation. Document gardening activities and weather data in a daily journal. Our memories, over time, may not remember precisely when our actions occurred, first siting of a problem or the date of a weather occurrence that may be a cause of the problem.
Recognize and assess the problem. Identify what the problem is, what condition (frost or freeze damage, wilting by lack of water, etc) or disease pathogen or pest is causing the damage. Be mindful of false accusations; just because you see a bug on a leaf doesn't mean it is the culprit. One handy tool to use in identifying the problem is a magnifying glass. Identify the pest by the type of damage caused by pest's feeding patterns or behavior or virus/ bacterial infection. It might be necessary to consult an expert or send a soil, water or plant sample to a lab for analysis for help in identifying the cause of the problem.
Once you know what is causing the problem, you can judge whether the potential damage justifies management. How serious is the problem? Not every perceived problem justifies action. Is it in a highly visible area? Is it a cultural problem, that is, a problem caused by improper techniques or maintenance?
Monitor and evaluate. Evaluate and monitor the situation to see if it spreads or is localized to that one plant. Continued inspection and record keeping may be needed. By keeping records of problems, if the same problem occurs from year to year, you are better able to determine the likely cause and come up with a solution.
Determine if the degree of damage being done warrants intervention. Sometimes the long-term strategy is to do nothing at all.
The factors of timing, number, stage of plant age and development, and location of plant need to be considered. Attacks on new tender leaves are more damaging than on leaves that have matured and hardened. Insects prefer the succulent new growth to hardened leaves. Low numbers of pests may be of minimal concern, depending on the pest. However, you must know your pests and plant. Small numbers of certain pests can be quite damaging. Pests on small, immature plants can be damaging, whereas they may have little effect on mature plants.
Problem management. Managing is not meant to control or eliminate all pests and disease. Total control and/or elimination is not possible. Most of our problems are a result of lack of a thriving soil ecology or poor maintenance practices. IPM stresses the management of a problem, rather than eradication. Management techniques are implemented, from the least toxic on up, after determination is made that the condition is unacceptable. Four management techniques are used when faced with a problem. Facets of each of these techniques could fill chapter, or books. Briefly:
Review cultural gardening techniques, could our gardening practices have caused the problem? Faulty plant culture, how plants are grown and maintained, cause many of the problems we face in the garden. This is the largest area where improvements can be made and encompasses the entire spectrum of home gardening.
Mechanical or physical techniques includes weed pulling, cultivating, pruning out disease and insect infestations, pulling out infected plants, handpicking insects and caterpillars, using screens and barriers such as row covers or diatomaceous earth. As an example, cardboard, metal cans or plastic barriers at the base protect vegetables from cutworms.
Biological techniques. Biological management of pests usually means the introduction into the garden of the pest’s natural enemies, living organisms such as parasitoids, predators and pathogens. Most of the natural enemies used are specific to the pests; a few are generalists and attack more than one insect pest. Natural predators we’re familiar with are lady bug beetles, praying mantids, katydids, dragonflies, damselflies, wasps, beetles, lacewings, flies, mites, true bugs, earwigs, thrips and ants.
Wasps such as the Trichogramma species are parasitoids. Using sprays of BT (Bacillus thuringiensis) bacteria, which are toxic only to caterpillars, and Bacillus popillae for milky spore disease to use against Japanese beetle grubs, are two common pathogen examples. Or introduce beneficial insects that target your specific insect threat. Lady bug beetles, aphid midges, green lacewings, bindweed mites, or beneficial parasitic nematodes are predators commonly introduced.
Chemical techniques. The last management practice and most harmful to the environment is the use of chemicals. Chemical applications are organic or synthetic, contact or systemic. Herbicides, pesticides, fungicides, miticides are used to kill. "Cide" means "kill." Most “cides” are contact-type chemicals that are sprayed or applied on to the plant or into the air. Systemic pest controls are applied to leaves, stems or through the soil for the plants absorption into its system. One should not eat any plants, leaves flowers or vegetables that have taken in systemic insecticides. Likewise, one should not eat plants, leaves, flowers or vegetables that have been sprayed with chemicals. Be on the safe side (read the label carefully for full instructions).
Organic “cides” are made from natural substances and break down quickly. Repeat applications may need to be made. Organic pesticide examples are insecticidal soaps, horticultural oils, and botanicals such as neem oil, sabadilla, rotenone, ryania, and pyrethrum (sometimes spelled pyrethrin). Some chemical remedies are approved for use in in certified organic operations. Look for the OMRI® (products approved by the Organic Materials Review Institute) name and symbol on the label.
Keep in mind that natural or organic remedies also kill beneficials along with the problem insects or weeds. Follow directions carefully and in recommended concentrations only. The label is the law. The users of these products are responsible for any damage, including drift damage. Use hand held spray bottles to spot treat the area to minimize toxic effect. Spray only on calm, windless days. A small, disposable sponge craft brush comes in handy in painting on “cides” (organic or synthetic) among ornamentals and even vegetables in close quarters.
The most harmful of IPM practices is the use of synthethic chemicals. Use synthetic pesticides, herbicides, miticides or fungicides as the last resort. Synthetic “cides” are made from chemical compounds not found in nature. Many have long-lasting residual effect; some have a shorter residual life. Over time, pests develop resistance to these synthetic substances and rebound even stronger. In addition, these synthetic compounds contribute or cause unintended and harmful environmental effects.
Let’s look at the decision to weed the garden as an example. Weeds are serious business having many scenarios and methods in dealing with them. We might ask ourselves first, why do you have a weed? Did the weed seed blow in from a neighbor’s or a vacant lot? Though we are powerless to prevent all problems, there are a few things we can do to help minimize them. Is the mulch thick enough? Are there bare spots in the turf? Reseeding with turf grass seed may be the solution (for a lawn), leaving no space for the seed to germinate. Is the soil healthy enough to support the plant you prefer to grow in that location (cultural methods)?
If it is not acceptable to you that even a new emerged weed be present in your landscape, start looking over your options. You may decide to jump to the second level: mechanical control (sometimes referred to as physical control) and handpick the weed, cultivate the ground to uproot the weed, or cut off the weed. If the weed is bindweed, a biological method might be used, such as the bindweed mite. You may choose to use the highest level, the chemical level and spray the weed with a soil-safe 20% vinegar solution or other organic herbicide. The step of last resort is using a synthetic toxic herbicide, often with residual value, and most harmful to the soil life (degree of harm depending on the herbicide).
Pulling out the weed could bring up buried weed seeds. Cultivating could bring up weed seeds, as well as losing soil moisture, and perhaps destroying roots of vegetables and other ornamentals nearby. If you decide to pull out the weed you might choose to prevent disturbed weed seeds from re-emerging by applying corn gluten meal to that spot.
There are many choices with every problem. If you don’t determine the best appropriate cultural management technique to apply to the problem, the problem will re-occur and you will be faced with jumping to the second or higher levels again in the future. In gardening, as in most activities, the best offense is a good defense, a healthy, thriving and diverse ecology above and below ground. Click on Pest Management for a bit more detailed explanation of IPM, or pick up a copy of IPM for Gardeners, A Guide to Integrated Pest Management, by Cloyd, Nixon and Pataky, Timber Press, 2004.
We are at the end of my recommended practices for creating organic landscapes in harmony with nature bringing us full circle to the first practice: Do nothing to harm the beneficial soil life, both below and above ground.
Happy, healthy and harmonious gardening! Angie Hanna, February 28, 2013.