Integrated Pest Management

As temperatures begin to warm in late winter, inspect your hemlocks for the presence of eriophyid rust mites. These plant sucking arachnids can cause needles to turn bronze and drop prematurely. To monitor these insects, place a sheet of white paper under a branch and tap vigorously. With a hand lens or magnifying glass, look for tiny, yellow, wedge-shaped mites on the paper. Also look for larger, fast-moving predatory mites that may be feeding on the pesty eriophyid mite. If you do not see any predatory mites, and if the beat test count is 50 or higher, you may want to treat the hemlock with insecticidal soap or horticultural oil. Only use horticultural oil if temperatures will be above freezing for 48 hours following application.

Wood ashes from your fireplace or wood stove are a rich source of potassium for the plants in your garden. Potassium is a major plant nutrient that is easily leached from the soil by rain. By following a few simple guidelines, you can do something good for your plants and practice an effective recycling technique. First, have your soil tested for pH level. Wood ashes are alkaline and should not be added to soil that is already testing in the alkaline range of 5.8 to 6.5. Do not use ashes from chemically treated or lead-painted wood, as these could harm your plants. Also, avoid using wood ashes around acid-loving plants like blueberries, azaleas, and rhododendrons. Apply the ashes evenly, and if possible, mix them into the soil. An average cord of wood will yield about twenty pounds of ash, which may be applied to a thousand square feet of soil. In flower beds, a good rule of thumb is one-half to one pound of ash per year per plant.

Inspect the twigs of your apple, crabapple, and cherry trees for the egg masses of the eastern tent caterpillar. The small, shiny black masses resemble Styrofoam and contain from 150 to 400 eggs. They are found near the ends of branches and can easily be pruned out. The caterpillars usually hatch in early March when the buds begin to open, spin silken tents in the crotch of the trees, and then emerge to begin feeding on the leaves. Large populations can be devastating and may defoliate the tree. Newly planted trees are especially vulnerable to stress from defoliation. If you miss the egg masses, hand picking is the best control of eastern tent caterpillars. Remove the webs by scraping them with gloved hands or by twirling them onto a stick and disposing of the nest.

Take the time to remove winter annuals like chickweed, wintercress, and annual bluegrass before they go to seed. Hand removal now will help reduce weed growth in the spring, and will cut down on the need for herbicides.

If you receive a houseplant for Valentine’s Day, it is a good idea to quarantine it from your other houseplants for a couple of weeks. It may host a harmful, unnoticed insect population that could spread to other houseplants in your home. At the end of two weeks, inspect your new plant carefully before placing it in its new location. If you discover a pest problem, such as aphids, whiteflies, or mites, treat your plant with 1% horticultural oil or insecticidal soap.

February is a good time to remove tree branches that are crowded, broken, diseased, or dead. Also, remove suckers to improve the tree’s vigor. If you suspect a tree is affected by a vascular disease, it is a good idea to sterilize your pruning tools by dipping them in a solution of disinfectant or bleach between cuts. This will prevent spreading the disease to other parts of the tree.

Leave a Reply