Weed scientists from Iowa and Minnesota have collaborated to produce a new publication that describes how weed emergence timing influences weed management systems. The bulletin, Relative emergence sequence for weeds of corn and soybeans, SA-11, was prepared by Doug Buhler, USDA/ARS-Iowa; Bob Hartzler, Iowa State University; Frank Forcella, USDA/ARS-Minnesota, and Jeff Gunsolus, University of Minnesota. Included are preliminary rankings of relative emergence for important weed species based on research data and observations of weed scientists in the North Central Region. The table is an abbreviated version of the rankings provided in the bulletin.

This publication is the first product of the Weed Management Issue Team sponsored by the Leopold Center for Sustainable Agriculture at ISU. The issue team is working to develop more precise and sophisticated methods for predicting weed emergence and growth.

To get a free copy of SA-11, contact the ISU Publications Distribution Center at 515-294-5247. Weed Seeds and the Seedbank: Implications for Weed Management, IPM-48, is another publication with basic information. Single copies are 50 cents each.

Relative emergence of common weeds of summer annual crops.*