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Cover crops a complimentary weed management tool

An extension crops educator sees cover crops as a compliment to other weed control tactics.

Liz Stahl with the University of Minnesota says herbicides remain the most effective tool for managing weeds in a conventional system.

“It’s just a part of the package, it’s another tool that you can use. We have seen reductions in weed emergence with broadleaf weeds for example (but) not necessarily with grassy weeds.”

She tells Brownfield the timing of cover crop termination and planting makes a difference.

“Even with an early planting, you’re not getting a tremendous amount of biomass at that point, but just that biomass did help enough if you applied a preemergence herbicide at planting as well to get at least 90 percent weed control. Which is a really good level of weed control.”

Stahl says to rely solely on cover crops for weed suppression it would require about 4,500 pounds of biomass per acre, which she calls “very difficult.”