Field Bindweed Control in the Fall

Field bindweed is an aggressive perennial weed that reduces crop yield and slows harvesting speed especially in soybeans and cereals. Eradication is impossible, but minimizing its impact in field crops is possible with a management strategy that includes a fall application of glyphosate at 1.5 L/ac (360 g/L concentration). The photo below was taken in late May of 2004 and compares field bindweed populations in the untreated area (right) versus a late September application of glyphosate (left).The previous fall a number of different tillage and herbicide treatments were applied to field bindweed that had regrown in this field after winter wheat harvest. The next spring, field bindweed first emerged at high densities in the areas of the field that were left untreated the previous fall. Where glyphosate had been applied the previous fall at 1.5 L/ac (360 g/L) field bindweed emerged much later (about the 7-8 leaf stage of corn),at significantly lower densities compared to the untreated areas and with minimal impact to the corn crop.

Unfortunately, one fall glyphosate application isn't going to have a long term impact. After all, we are dealing with a species with a very extensive underground root system that allows it to bounce back quickly. However, a management stratgey that incorporates fall glyphosate applications, with cover crops (i.e. underseeded red clover) and in-crop treatments that remove field bindweed top growth (through effective herbicides or tillage) will go a long way to minimizing the impact of this creeping perennial. To search for effective in-crop herbicide options for field bindweed in corn, go to www.weedpro75.com A big thanks to Peter Smith and Dr. François Tardif (University of Guelph) for collaborating on this project.