Termination of cover crops prior to no-till planting of soybean is typically
accomplished with burndown herbicides. Recent advances in cover-crop
roller–crimper design offer the possibility of reliable physical termination
of cover crops without tillage. A field study within a no-till soybean
production system was conducted in Urbana, IL, from 2004 through 2007 to
quantify the effects of cover crop (cereal rye, hairy vetch, or bare soil
control), termination method (chemical burndown or roller–crimper), and
postemergence glyphosate application rate (0, 1.1, or 2.2 kg ae
ha−1) on soybean yield components, weed–crop interference, and
soil environmental variables. Biomass of weeds surviving management within a
soybean crop following either a vetch or rye cover crop was reduced by 26
and 56%, respectively, in the rolled system compared to the burndown system.
Soybean yield loss due to weed interference was unaffected by cover-crop
termination method in soybean following a rye cover crop, but was higher in
the rolled than burndown treatment in both hairy vetch and bare soil
treatments. In soybean following a rye cover crop, regardless of termination
method, yield loss to weed interference was unaffected by glyphosate rate,
whereas in soybean following a vetch cover crop or bare soil, yield loss
decreased with glyphosate rate. Variation in soybean yield among cover crops
and cover-crop termination treatments was due largely to differences in
soybean establishment, rather than differences in the soil environment. Use
of a roller–crimper to terminate a cover crop preceding no-till soybean has
the potential to achieve similar yields to those obtained in a chemically
terminated cover crop while reducing residual weed biomass.