Even so many farmers feel they would have a tough time staying in business without pesticides. Quick and direct pesticides help protect farmers from ruinous losses caused by a sudden pest outbreak. They also allow use of more pest-prone practices like larger fields planted to a single crop so that farmers can specialize in fewer crops, maximizing efficiency. And though a small minority of farmers have successfully abandoned pesticides altogether most experts and even some organic farmers admit that quitting cold turkey is not feasible for every crop or in every region of the country.
Not surprisingly, there is new interest in an option that has been around for decades; a multi-pronged strategy known as integrated pest management that many experts say can reduce pesticide use by 50 percent or more without lowering yields. Farmers choose among a variety of techniques including rotating crops, planting pest-resistant varieties and encouraging the build-up of natural enemies to prevent pest outbreaks. Pesticides are used as little as possible and only if non-chemical measures fail to keep pests below damaging levels.
Researchers continue adding to the IPM arsenal. One new technique, pioneered by Metcalf and approved last month by the U. S. Environmental Protection Agency, uses poison bait laced with a chemical from the host plant that entices the pests to eat the poison; insects that dont naturally feed on the crop ignore the chemical cue and escape the poison. West Coast artichoke and cranberry growers are experimenting with tiny roundworms to kill insects. Biologists at Cornell University are developing a potato variety with sticky leaf hairs that repel beetles and aphids, and entomologists at Washington State University are experimenting with a common potato-field weed that beetle find so tasty they ignore nearby potatoes.
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