Types of Garden Enemies
Control. Experience has shown that after a community has endured hordes of beetles for several years their numbers decline, partly due to natural parasites. Tiphia wasps, introduced from Japan, have been released from Connecticut to Virginia. Grubs have been given milky disease, in the form of bacterial spore dust applied to turf, 1 teaspoon at 3-foot intervals. Some succumb to blue disease, probably of virus origin, and others to a green fungus.

DDT, applied to the turf at the rate of 6 pounds of a 10% dust for each 1000 square feet, controls grubs for at least 3 years. Chlordane, 5 pounds of a 5% dust for the same area, has a quicker reaction but perhaps a shorter residual effect. Some proprietary formulations combine DDT and chlordane. Aldrin is also effective. Treatments may be made in May or early autumn. The dust can be mixed with several times the amount of sand, broadcast evenly or applied with a fertilizer spreader, then washed in well with the hose. If power apparatus is available, the chemicals can be sprayed on the lawn, keeping children and pets away until it has dried.

Spraying with DDT, methoxychlor, or lead arsenate often enough to protect new growth will keep foliage of roses and other plants from being chewed up by beetles, but there is little to do about blooms except to cut your best buds as they show color and enjoy them in the house during July and August. Roses are best in June before the beetles appear and in the fall when most of them are gone; so there is no reason at all to stop growing roses just because you live in a Japanese beetle area. For grapes, raspberries, and other fruits use a rotenone spray with a sticker sold especially for Japanese beetles. Methoxychlor, which is less poisonous to man than DDT, can be used on some fruits. Bright yellow traps catch beetles, but they attract far more than they trap, so they are not advised for small gardens.

The name goes back to the Middle Ages, when these garden friends were dedicated to the Virgin, becoming "beetles of our Lady." Lady beetles are broadly oval, with head nearly concealed by the thorax. Those that are red with black spots often prey on aphids. The small two-spotted lady beetles are common not only in gardens but in houses in winter. They don't do any harm, and they do help clean up lice on the ivy tips, so don't kill them. There is one keeping me company as I type this, sometimes on the windowsill, sometimes perched on the typewriter. The sluglike larvae, black, marked with blue and orange, eat aphids as avidly as the adults.

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