Net Returns from Stale Seedbed Plantings of Soybean (Glycine max) on Clay Soil

Abstract

Field studies were conducted for three years in each of two successive experiments and analyzed to determine net return from stale seedbed plantings of soybean. Treatments in the first experiment were early May and late May/early June plantings in seedbeds that had combinations of tillage at various times between harvest and planting, incorporation of trifluralin, or no preplant tillage. Treatments in the second experiment were irrigated and nonirrigated stale or no-till seedbed plantings with weed control treatments that included POST cultivation plus combinations of preplant foliar-applied (PFA) glyphosate, PRE metribuzin, and POST herbicides. Results indicate that 1) early planting of soybean resulting from use of a stale seedbed will result in higher net returns when irrigation is used, 2) use of a wheat cover crop does not justify the expense, 3) soybean planted in a no-till seedbed will result in net return similar to that from plantings in fall-tilled, spring-tilled, or prepared seedbeds, 4) use of only a PFA herbicide plus POST cultivation in a stale seedbed planting where competitive weeds such as common cocklebur appear later will result in a significant reduction in net returns, and 5) use of PRE herbicides in conjunction with PFA herbicide and POST cultivation in a stale seedbed planting will result in the highest net return with the least input.