Two cooperators gave serious examination to the use of cover crops to control weeds. Jeff and Gayle Olson, Mount Pleasant, compared mechanical and chemical means of removing a cover of springseeded rye from the ridge (Table 7). The herbicide band did a better job, as shown by the significant difference in soybean yield and grass counts. In a second trial, in corn, the Olsons compared 1) springdrilled rye, removed mechanically, to 2) no rye plus an herbicide band. Again, the rye treatment yielded significantly less. The rye had dried the soil by planting time, and the planter alone couldn’t remove all the rye from the ridge shoulders.
Dick and Sharon Thompson, Boone, compared the effect of different fall-seeded cover crops on corn: 1) rye; 2) rye/hairy vetch; 3) oats/hairy vetch/canola; and 4) no cover crops (Table 7). The no-cover treatment and the oat/vetch/canola treatment yielded significantly better than the two treatments that included rye. There were no significant differences in numbers of broadleafed weeds. In a second trial in corn, the Thompsons compared; 1) fall-seeded rye; 2) fall drill-only (no seed); and 3) a check treatment of no rye or drill disturbance. This time neither corn yields nor weed counts were significantly different.