Submitted to: Research Report North Central Weed Science Society United States
Publication Type: Other
Publication Acceptance Date: 12/20/1996
Publication Date: N/A
Citation: Interpretive Summary:
Technical Abstract: This research was initiated to evaluate control of common waterhemp in soybean with various herbicide combinations. The study was established in a grower's field near Greenville, Illinois. The soil was a Cowden silt loam with a pH of 6.2 and 2.2% organic matter. Prior to no-till planting the field was sprayed with paraquat at 0.50 lb/A plus NIS at 0.25% for control of existing vegetation. Pioneer 9362 soybeans were planted 1.0-inch deep on May 23 in 30-inch rows. Treatments were arranged in randomized complete blocks with 3 replications of plots 10 by 30 feet. Herbicides were applied with a CO2 backpack sprayer delivering 20 gpa and equipped with 8003 flat fan nozzles for preemergence and 8002 flat fan nozzles for postemergence applications. Soybean injury was greatest 8 days after application of postemergence herbicides. No herbicide treatment caused greater than 3 percent soybean injury 32 days after application of postemergence herbicides. All postemergence herbicide treatments provided 98 to 99 percent control of common waterhemp 8 days after application except imazethapyr or bentazon plus chlorimuron plus thifensulfuron plus sethoxydim. Control of common waterhemp was reduced 32 days after application of postemergence herbicides for all treatments except imazethapyr following pendimethalin.