Pesticides: Gardening Without DDT

Dibrom is morbid spelled backward.

Happily, it is also one of many pest controls that can keep gardens green with out the dangers of DDT and similar chlorinated hydrocarbon insecticides.

Others are helpfully summarized in the current issue of Cry California, an eco logically astute magazine that deserves to be better known outside its state.

The best defense against common pests, says Cry California, is simply to keep the garden well watered, fed and weeded. A strong blast of water from the garden hose is often effective against leafhoppers and spittlebugs. Such nat ural predators as birds, ladybugs and lacewings wreak havoc with aphids, caterpillars and oak moths. When poisons must be used, the problem is how to avoid overkill. The preferred pesticides are "botanicals," or natural poisons extracted from plants—for example, nicotine sulphate, rotenone and pyrethrum. Their effectiveness, though, is limited to certain chewing pests and sucking insects, such as Diabrotica and thrips. Some synthetic poisons, for example diazinon, kill more kinds of bugs than botanicals but are also more persistent. The newest synthetic poisons are the highly toxic "systemics" (Di-syston and Meta-systox-R), which kill sucking pests after being absorbed by plants. On the market for only two years, systemics may eventually prove undesirable for garden use.

Thoughtful gardeners should choose the least toxic control available; if it is a poison, they should buy the smallest quantity necessary. Above all, says Cry California, swear off DDT and other chlorinated hydrocarbons. The ecosystem you save will be your own.