INTEGRATED WEED MANAGEMENT AT A CROSSROADS

Crops bred to be resistant to multiple herbicide modes of action hold the promise to reduce the glyphosate resistance problem that plagues some 60 million acres of US corn, soybean and cotton. However, these new crops have been bred to be resistant to 2,4-D and dicamba, both plant growth regulator herbicides. While these herbicides are highly effective, they have a long history of drifting to adjacent fields and field edges and are equally or more active on many non-target broadleaf plants. This projects sets out to quantify the impact of such drift events on floristic diversity and the cascading effects on the insect community. We will also study the weed suppressive effects of cover crop cocktails in an attempt to identify mixtures of cover crops that would help take the weed suppressive pressure off herbicides. Finally, we know that practices like cover crops are likely to require additional management time and cost. In order to better understand the factors that hold such practices back we will analyze the true constraints to adoption of such alternative methods like cover cropping.