Proceedings 2006

Indiana Certified Crop Adviser Conference

Weed Competitive Loads in Roundup Ready_© Corn

Managing weeds in Roundup Ready corn presents some unique opportunities and challenges. Many users will be tempted to reduce or eliminate the use of soil-applied residual herbicides and control weeds with only glyphosate applied postemergence to reduce cost. However, evolution of weed populations which are not effectively controlled in Roundup Ready soybeans might suggest that reducing the use of other herbicides in Roundup Ready corn results in greater risk of poor weed control and yield loss due to weed competition in corn. This presentation will focus on the value of soil-applied residual herbicides in Roundup Ready corn production and the effectiveness of various tactics in reducing early-season weed competitive loads and protecting corn yield.

Bill Johnson

Dr. Johnson is an Associate Professor of Weed Science in the Department of Botany and Plant Pathology at Purdue University. He has statewide responsibilities for weed science extension and research in agronomic crops. Dr. Johnson has extensive experience in the biology and management of weeds common to no-till systems and herbicide-resistant weeds and crops. Dr. Johnson is the Communications Editor for the North Central Weed Science Society (NCWSS) and an active member of the Weed Science Society of America (WSSA) and the American Society of Agronomy (ASA).