Stacking tools on a wheel hoe to improve weed control for small-scale farmers

Small-scale vegetable farmers rely on hand tools for weed management, including wheel hoes, stirrup hoes, and tine rakes. They also use hand pulling of weeds in the crop row, with costs increasing in proportion to weed density. The Terrateck double wheel hoe offers improved efficiency by straddling the crop row and weeding both sides. We evaluated the effects of single tools and tool combinations or “stacking” with the Terrateck double wheel hoe, measuring weed control efficacy and crop mortality. In two years of field experiments, six single tools and all possible two- and three-tool combinations were tested. Tools included: biodiscs, finger weeders, tine harrows, L-sweeps, preci-discs, and torsion weeders. Bush bean and table beet were used as test crops. Tool stacking improved weed control efficacy compared to single tools, but average benefits were modest, with gains of 12 and 13% over single tools in bush bean and table beet, respectively. Regression analysis and observation of treatment rankings indicated that L-sweeps were a critical tool for top-performing treatments. In bush bean, for example, four tool combinations with L-sweeps had an average efficacy of 69 ± 15% compared to 37 ± 11% for all other treatments. The combination of L-sweeps, tine harrows, and torsion weeders provided the greatest weed control efficacy in both bush bean and table beet. Tool stacking did not affect bush bean mortality, which ranged from 0.9 to 2.0 plants killed per 1.5 m of row. However, in one experiment, stacking increased table beet mortality from 4.1 plants per 1.5 m of row for single tools, to 6.9 plants per 1.5 m of row for combinations with two tools. Overall, the Terrateck double wheel hoe provides small-scale farmers an opportunity to improve efficiency and, with the ability to stack tools, improve weed control efficacy.