By Dwight Lingenfelter
Dense populations of winter annual weeds (e.g., common chickweed, henbit, marestail, winter annual grasses, and others) can compete with fall-seeded small grains in late fall and early spring and slow the rate of crop development, potentially reducing yield. Harmony Extra (or generic equivalent) is still one of the most widely used broad-spectrum herbicides for broadleaf weed control. Fall applications have been more consistent than spring applications for weed control in regional trials. However, it has its weaknesses, and other options or tank-mixes should be considered. The table below summarizes common fall herbicide options for small grains. Here are some "best bets" for common problem weeds:
- Common chickweed: Harmony Extra and Quelex are still effective on it in many parts of the region; however, there are pockets of resistant populations starting to thrive. Tank-mix with Starane Ultra/Pixxaro or include Metricor (metribuzin) in your spray program if ALS-resistant (Group 2) chickweed is prevalent. It might be best to make fall applications to control chickweed since it tends to get unruly by spring.
Source : psu.edu