Considerations for Spring Burndown Programs for Weed Control
As it has started to warm up, folks are ready to implement early-spring weed management programs, especially in fields with infestations of winter annuals like field pennycress and marestail (horseweed). Spring burndown (preplant) herbicide programs should target winter annual plants at the rosette stage, prior to stem elongation (bolting), for consistent control. Cold nights (<40°F) will reduce activity of herbicides, particularly for glyphosate. With cool weather conditions, it is recommended to wait for a few days until it warms up before applying herbicides.