Fall herbicide application for soybeans shows some potential, according to research by University of Illinois weed scientists Aaron Hager and Christy Sprague.
Their study is geared primarily for the southern third of Illinois, where weed growth starts earlier in spring than in areas farther north.
They have evaluated four treatments: Canopy at two rates, alone or with Roundup and 2,4-D; Roundup & 2,4-D; Canopy XL at two rates, alone or with Roundup & 2,4-D; Sencor at two rates, alone or with Roundup & 2,4-D. They applied the treatments in fall and also 30 days prior to planting.
"Results were both herbicide and rate dependent," Hager reports. "Some fall-applied treatments at the higher rate worked well, but some of the lower rates needed a burndown in spring."
They plan to repeat the research this fall.