Development of a Regional Bulletin on Glyphosate

Robert Hartzler, Faculty, Agronomy


Weeds infest every corn and soybean field in Iowa at densities capable of causing major yield losses.  Herbicides are the primary control tactic used by most farmers, and farmers spend approximately $20/A for herbicides.  Glyphosate is the most widely used herbicide in Iowa and the Midwest, it is used on more than 95% of the soybean acres and 50% of the corn acres in Iowa.


Weed management can be improved through more efficient herbicide use.  This potentially can reduce crop production costs, enhance yields, and reduce the amount of pesticide introduced into the environment.  The goal was to improve the efficiency of glyphosate use by developing a bulletin that would provide detailed information regarding the biological, chemical and environmental factors that influence the activity of glyphosate


Funding was obtained from a number of private (BASF, Bayer, DuPont, etc.) and public sources (state Soybean Associations, USDA IPM program) to develop a series of bulletins on glyphosate stewardship.  A regional bulletin titled Understanding Glyphosate to Increase Performance, GWC-2, was developed with co-authors from the University of Wisconsin, Purdue University and University of Guelph.  More than 20,000 copies of the bulletin have been disseminated since printing in early 2007.


It is difficult to access the impact of a written bulletin on the actions of farmers; however, the financial support provided for this project and the large distribution suggest a demand for the information provided.  An indication of the value of the information was provided by an unsolicited communication with an independent crop consultant.  The consultant had been at a meeting where the bulletin had been distributed.  He wrote that he was impressed with the quality and content of the material, stating that it was of real value in having all of the information in a single publication.

July 25, 2007
100  Corn and Soybean Production and Protection


Page last updated: August 2, 2007
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