Overlapping Residual Herbicides May Be Necessary for Effective Weed Management

Weed management is always a critical component of crop production, but in sunflowers, it poses unique challenges. Compared with many other crops, there is a limited selection of herbicides that are labeled for sunflowers, especially postemergence herbicides.

Certain herbicides can be applied postemergence for effective control of grass weeds (i.e., clethodim [Select Max]). Additionally, there are herbicide traits that allow for the application of select ALS-inhibiting herbicides in Clearfield (i.e., imazamox [Beyond Extra]) and Express (i.e., tibenuron [Express]). While these herbicides can effectively manage many broadleaf weeds and some grass weeds, kochia and waterhemp in South Dakota are resistant to these herbicides.

Preemergence herbicides will be paramount to manage kochia and waterhemp in sunflower production.