Controlling winter annual weeds
Todd Whitney
Wednesday, March 11, 2026
Record winter high temperatures are causing earlier weeds emergence; so now is the time to control winter annual weeds in alfalfa. Thin field stands combined with open soil surfaces and adequate moisture can result in high weed pressure. So, prior to alfalfa shoot green-up or dormancy break, scout fields for early green winter annual weed patches of pennycress, downy brome, mustards, cheatgrass, and shepherd’s purse. Left unchecked, these weeds can lower first cutting hay yield, quality and palatability. Also, excessive weeds can extend dry-down and lengthen harvest time.