Nonchemical options for delaying weed resistance to herbicides in midwest cropping systems

Herbicide-resistant weeds are becoming a major problem in the Midwest, and strategies must be adopted to delay further selection, Strategies of rotati ng and tank-mixing herbicides with different modes of actions should be eff ective, but adoption may be limited and certain limitations may exist. Ther efore, integrating nonchemical practices that indirectly lower selection pr essure or restrict the growth of resistant populations is desirable. Approp riate integration of mechanical weeding, crop rotation, increased crop comp etition, and decision aids may further delay the development of resistance. Understanding the effect of these practices on weed population dynamics is required to more accurately predict their contributions toward resistance management. This knowledge will aid in justifying the adoption of improved management systems.