Between-row mower design for weed control in organically grown no-till soybeans

Abstract

Weeds are a major challenge in organic no-till soybean production. They impair crop growth and result in yield loss. Innovative weed control methods need to be developed and experimented with in organic no-till agriculture to reduce weed density and improve organic yield. In 2017, mowing between crop rows was compared to cultivation in two central Missouri locations (Herman and Bradford Research Center). Cereal rye (Secale cereale L.) was used as a cover crop in some mowing treatments. Treatments included 1) pre-plant tillage + cultivation; 2) pre-plant tillage + mowing for weed control; 3) organic no-till using cover crops + mowing for weed control; and 4) organic no-till using cover crops + no subsequent weed control. Weed control treatments were conducted when seedlings were 4 in (10.2 cm) and repeated as needed until canopy closure. Broadleaf and grass biomass was collected between-row and in the row of organic soybeans to evaluate the efficacy of the weed treatment. Weed biomass was not significantly different at either testing locations. Yield from mowing with cover crop was 22 percent higher than cultivation treatments in both locations. Mowing between rows and cultivation has high potential for crop damage during operations. Between-row mowing with cover crops has great potential for weed control in organic soybean production and can be utilized in organic no-till.