Replicated field experiments were conducted at the Northeast Research Station, St. Joseph and the Macon Ridge Research Station, Winnsboro from 1982-85 to evaluate herbicides for control of annual grasses including broadleaf signalgrass, goosegrass and crabgrass, and seedling johnsongrass in cotton on silt loam soils. The performances of six commercially available herbicide treatments which occurred in the varied experiments were compared. These treatments were Treflan 1.0 lb/A preplant incorporated. Zorial 1.5 lb/A preplant incorporated, Dual 2.0 lb/A preemergence surface, Cotoran 1.2 lb/A preemergence surface, Poast 0.15 lb/A + 1 qt/A crop oil concentrate postemergence over-the-top and Fusilade 0.13 lb/A + 1 qt/A crop oil concentrate postemergence over-the-top. Postemergence treatments were applied to 1-3 tiller annual grasses or 4-8 leaf seedling johnsongrass, usually within 1 month of planting. Experiments were rated 4-6 weeks after preemergence treatments or 7-14 days after postemergence treatments.

Treflan and Poast provided the highest average annual grass control at approximately 95%. These two treatments were also distinctly most consistent with control ranging from 90-100% with Treflan and 87-100% with Poast. Zorial gave an average of 92% control, ranging from 80-100%. Dual, Cotoran and Fusilade averaged approximately 85% control, but each of these treatments resulted in less than 75% control in at least one experiment.

Fusilade gave 100% seedling johnsongrass control at each observation, while Poast provided an average of 97% control, ranging from 94-100%. Treflan gave an average of 94% control, ranging from 90-100%. Zorial averaged 87% control, with a range of 80-93%. Dual and Cotoran each provided very erratic seedling johnsongrass control, ranging from 20% to near 100%, but averaging less than 60%.