Improving the ability to predict emergence timing of weeds in row crops has been a major research emphasis at Iowa State University in recent years. The latest product of this research is a poster called Weed emergence sequences: Knowledge to guide scouting and control. It depicts the emergence sequence of 16 important weeds of the northern Corn Belt.

This poster is available in 18" by 24" and 8.5" by 11" formats. Single copies of each poster are free. Multiple copies of the large poster are $1.00 and the smaller poster, $0.25, plus shipping and handling if mailed. The poster can be obtained at ISU "Extension Distribution Center", 119 Printing and Publications, ISU, Ames, Iowa 50011 or by calling (515) 294-5247. Ask for IPM 64 (large poster) or IPM 64s (small poster).

This poster is a joint project of ISU, University of Illinois, University of Minnesota, University of Wisconsin, and the USDA-ARS. Much of the information used to develop the poster was developed by the Weed Management Issue Team sponsored by the Leopold Center for Sustainable Agriculture, whereas funding to print the poster was obtained through the North Central Integrated Pest Management Program. Residents of Illinois, Minnesota, and Wisconsin interested in obtaining the poster are encouraged to contact their state extension weed specialists.

ISU has two bulletins that provide additional information on weed seeds and emergence. IPM 48, Weed seeds and the seedbank: Implications for weed management and SA 11, Relative emergence sequence for weeds of corn and soybeans. These bulletins also are available through the ISU Extension Distribution Center.