Establish Natural Defenses
A good anti-pest defense involves building up the soil in the yard with organic matter. Mulching is the easiest way to add organic matter. As the mulch slowly breaks down, earthworms hasten this process by pulling the materials down into their tunnels, thereby adding vital nutrients and improving soil structure and drainage. This natural process provides longterm help to trees and shrubs stressed by defoliation by tent caterpillars. Spread a 3- to 4-inch thick layer of organic material of some kind on the ground around each tree or shrub all the way out to the dripline (the furthest extent to which the branches extend). The very best mulches are composted municipal sludge, mushroom compost, leaf mold, or commercial compost .[752 700] Next best is chopped leaves. Grass clippings are not satisfactory, because they tend to form a mat that resists water penetration. Bark_mulch [750 300] is long-lasting, but adds little to the soil around tree roots. Peat_moss [750 100] makes a good mulch as long as it’s mixed with coarser materials such as chopped leaves or shredded paper. Used alone, it tends to crust over and repel water.
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Besides building a rich soil base, it is a good idea to encourage the many insects and animals that normally prey on tent caterpillars. These natural predators come in all shapes and sizes. While many are insects themselves (tachnid flies, braconid and ichneumon wasps, paper wasps, shield bugs, ground beetles, ants), others are spiders, microscopic organisms, small animals such as white-footed mice, shrews, chipmunks, voles, and squirrels, and many insect-eating birds. The more of these different kinds of predators live in your yard, the fewer pest insect problems you will have. They will take up residence in a yard that includes their favorite plants and other foods. The greater the variety of plants on your property, the greater will be the variety of natural enemies of tent caterpillars that will be attracted to it.
Keep Trees, Shrubs, And Plants Vigorous
Unless the underlying stress that made your plants vulnerable to tent caterpillar attack is identified and corrected, the pests may return next year. Give some thought to the affected plant’s situation. Make an effort to improve its vigor by watering it during dry periods over the summer and fertilizing it in the fall, if appropriate. Prune any injured or broken branches or stems cleanly and carefully. Mulch it to discourage weeds, hold soil moisture, and improve the health of the soil beneath it. Make sure the plant is getting enough light as the surrounding plants may grow and block the sun a bit more.
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Attract Beneficial Insects To The Yard
Birds, spiders, and predator insects will kill many more tent caterpillars than a homeowner armed with insecticide ever will. If you don't use broad-spectrum insecticides, you should have lots of beneficial insects 6 72 300C such as minute parasitic wasps, ground beetles, spiders and ants. All are great caterpillar destroyers.
If you do not have very many beneficial insects already, introduce some into your home landscape to patrol for caterpillars. Many kinds of beneficial_insects [722 300] are available from mail-order suppliers. Properly introduced into the yard, they will search out and feed on the tent caterpillars and other pests as well.
Click here for more information about Buying_Beneficial_Insects . [2 27 400]
Feed and House Beneficial Bugs
Encourage the natural predators of tent caterpillars to stay in your yard by providing them with a tempting variety of their favorite plant sources of pollen and nectar. One product, a wildflower mix called Border Patrolä, is a mix of insectary_plant_seeds [722 400] particularly attractive to beneficial insects, and includes evening primrose (Primula), wild buckwheat (Eriogonum), candytuft (Iberis), baby blue-eyes (Nemophila Menziesii), bishops flower (/Liz--which one is this? Several different genera listed in my refs///), black-eyed Susan (Rudbeckia hirta), strawflowers (Helichrysum or Helipterum?///), nasturtiums (Tropaeolium), angelica, and yarrow (Achillea).
Wasp House Trick: Paper wasps hunt tent caterpillars to provide food for their young. They will nest in your yard if you provide adequate shelter. Build some small boxes, about 6 inches square, and leave them open at the bottom. Paint them brown or black and fasten them to stakes placed in sunny areas. The wasps will build nests inside the boxes. /Liz--I found this in a recent issue of O.G. and rewrote it--phj///
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Support Birds All Year Round
Songbirds eagerly probe the bark of trees and gobble up as many tent caterpillar eggs as they can find. Among the most helpful egg hunters are bluebirds, blue jays, tufted titmice, and chickadees. Black and yellow-billed cuckoos, Baltimore orioles, redwing blackbirds, phoebes, red-eyed vireos, robins, and downy woodpeckers will eat the caterpillars, too. Encourage bird allies to take up permanent residence in the area by putting out seed and other foods such as suet_cake [612 300] in a suet_cage [610 900] for them. In the spring and summer reduce the amount of bird food you have in your bird_feeders, [610 1] but keep setting out snacks during this time to encourage more bird families to live in your yard.