Submitted to: Research Report North Central Weed Science Society United States
Publication Type: Other
Publication Acceptance Date: 12/22/1996
Publication Date: N/A
Citation: Interpretive Summary:
Technical Abstract: We designed this research to evaluate the efficacy of selected soil-applied herbicides and sequential applications of soil-applied herbicides followed by imazethapyr or fomesafen for control of common waterhemp in soybean. The experiment was established on 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 soybeans, the area was treated with paraquat at 0.5 lb/A plus NIS at 0.25% to control existing vegetation. Pioneer 9362 soybeans were planted 1.0-inch deep on May 23 in 30-inch rows. Treatments were arranged in randomized completed blocks with 3 replications of plots 10 by 25 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. No soybean injury was observed from any soil-applied herbicide 14 days after application, however injury became apparent by 29 days after application. Control of common waterhemp from all soil-applied herbicides was 97 percent or greater 14 days after application. Sequential applications of postemergence herbicides provided added control of waterhemp compared to most soil-applied herbicides alone.