Influence of Tillage Systems on Giant Foxtail,Setaria faberi, and Velvetleaf,Abutilon theophrasti, Density and Control in Corn,Zea mays

Abstract

Giant foxtail density in corn was greater under no-till and chisel plow tillage systems than conventional or till plant. Giant foxtail density in no-till was 1400 shoots/m256 days after corn planting compared to 170 under conventional tillage. Velvedeaf density was greater under conventional tillage than all other tillage systems. Velvetleaf density was 120 plants/m256 days after corn planting under conventional tillage compared to 20 in no-till. Control of giant foxtail was often less under no-till or chisel plow conditions than conventional or till plant with the same herbicide treatment. Giant foxtail control with metolachlor treatments was affected less by tillage than similar treatments containing alachlor. Velvedeaf control was less with conventional tillage than other tillage systems when less than 1.7 kg/ha of atrazine was applied. Corn injury was not influenced by tillage systems. Corn yield was not affected by tillage systems under weed-free conditions. Several herbicide treatments resulted in corn yield similar to the weed-free under conventional tillage, but no herbicide treatment produced corn yield similar to the weed-free control under no-till conditions.