Research on Jointed Goatgrass In Utah

The Intermountain region includes research conducted in Utah by Dr. John Evans, a Weed Scientist at Utah State University.  Evans along with Dr. Don Morishita from the University of Idaho recently concluded integrated jointed goatgrass management research.  The four-year project compared two different crop rotations, conventional and no-till systems, and various planting dates for jointed goatgrass management. 

Preliminary results from their experiment show that incorporating safflower in wheat-fallow rotations, with safflower following wheat, allows producers to use pre-emergence safflower herbicides to reduce jointed goatgrass populations.  Cultivation, in general, helped to reduce the impact of jointed goatgrass infestations.  Post-harvest cultivation in the fall following winter wheat, the following spring prior to planting safflower, and while establishing summer fallow during the third year of the rotation reduced jointed goatgrass populations.  Morishita said "In 2000, jointed goatgrass population density was three-fold greater under minimum tillage than under conventional tillage."  Adverse precipitation levels are likely causes for these great differences in density.  Evans concluded that, "Early wheat planting dates are more favorable for a good stand of wheat while jointed goatgrass is small.  This more than compensates for loss of later tillage and late planting."

Currently Dr. Evans is evaluating the best management practices for control of jointed goatgrass in winter wheat in the intermountain states and a separate study evaluating the effects of fallow tillage to control jointed goatgrass.  Both studies are being funded by the National Jointed Goatgrass Research Program.  To find out more about the research conducted by Dr. John Evans please contact him at jevans@mendel.usu.edu or contact Doug Schmale, JGG Extension Coordinator.