Pesticide drift is persistent problem for farmers

Organic and specialty crop growers are trying to make a living off the rising consumer interest in locally grown and organic foods.

But the smaller farms are often islands surrounded by a sea of conventionally grown crops that get sprayed with herbicides, insecticides and fungicides.

Pesticide drift is a serious concern for them, and they've come up with a variety of defenses.

Many plant buffer strips. Twelve states participate in a registry of organic and other farms to tip aerial and ground sprayers off to areas they need to avoid. And in Iowa, a group has produced a pamphlet that instructs farmers how to protect vulnerable crops.

The aerial spraying industry and pesticide manufacturers, meanwhile, say they've made big strides in controlling drift through education and new technologies.