Impacts of Single- and a Multiple-Species Cover Crop on Soybean Relative to the Wheat-Soybean Double Crop System

Abstract

Core Ideas• Cereal rye and wheat cover crops produced similar levels of biomass as a multi-species mix.• A preemergence herbicide was required to achieve acceptable, consistent levels of weed control.• Cover crop treatment did not significantly impact soybean yields.• A wheat-soybean double crop system reduced soybean yields in four of five site-years. AbstractThe integration of cover crops into soybean (Glycine max) production has many potential benefits, but little information has been collected on the impact of multiple-species cover crops on the subsequent soybean crop relative to the common wheat (Triticum aestivum)soybean double crop. Experiments were established at the West Tennessee Research and Education Center in Jackson, TN in the fall of 2014, 2015, and 2016 and the Research and Education Center in Milan, TN in the fall of 2014 and 2015. Winter treatments included a winterfallow, cover crops including cereal rye (Secale cereal), wheat, crimson clover (Trifolium incarnatum), and a five-way mixture [cereal rye, oats (Avena sativa), oilseed radish (Raphanus sativus), crimson clover, and hairy vetch (Vicia villosa), referred to as mix], and wheat for grain.Treatments were split to evaluate weed suppression relative to the preemergence herbicide, S-metolachlor + metribuzin. Largest levels of biomass (commonly 4000+ lb/acre) were associated with the wheat for grain, cereal rye, and mix treatments. Weed control was greatest in cereal rye, wheat for cover and mix treatments, but no treatment provided consistent, acceptable weed control without the use of the preemergence herbicide. Soybean yields were not impacted by cover. The delayed planting of soybeans after wheat for grain negatively impacted yields in four of five site-years by an average of 20 bushels/acre. Results suggest impacts of single-or multiple-species cover crops on soybean yields may be negligible. Market prices, incentives, and long-term benefits may be more important than short-term costs/benefits when selecting a production system.

Influence of cover crops on soybean yield and partial returns as an alternative to double‐crop soybean in Arkansas

“…These results support the findings of Raper et al. (2019) who reported that, although soybean yield, ranged from 2605 to 4250 kg ha −1 , soybean yield was unaffected by cover crop treatment. Raper et al.…”

“…On average, cover crops increased soybean yield by almost 430 kg ha −1 compared to double-crop soybean. These results support the findings of Raper et al (2019) who reported that, although soybean yield, ranged from 2605 to 4250 kg ha −1 , soybean yield was unaffected by cover crop treatment. Raper et al (2019) also concluded that soybean following winter wheat harvested for grain yielded significantly less, ranging from 1230 to 2500 kg ha −1 , due to delayed soybean planting.…”

“…These results support the findings of Raper et al (2019) who reported that, although soybean yield, ranged from 2605 to 4250 kg ha −1 , soybean yield was unaffected by cover crop treatment. Raper et al (2019) also concluded that soybean following winter wheat harvested for grain yielded significantly less, ranging from 1230 to 2500 kg ha −1 , due to delayed soybean planting. Soybean following cover crops also yielded on average 220 kg ha −1 more than soybean following winter fallow.…”

“…Raper et al. (2019) also concluded that soybean following winter wheat harvested for grain yielded significantly less, ranging from 1230 to 2500 kg ha −1 , due to delayed soybean planting. Soybean following cover crops also yielded on average 220 kg ha −1 more than soybean following winter fallow.…”

Cover crop termination timings and methods effect on cotton (Gossypium hirsutum L.) development and yield

“…Grass weed control ranged from 29 to 72%. The lack of weed control observed may be due to low levels of biomass previously discussed or inconsistent cover crop stand due to a cover crop blend being planted (Raper et al., 2019); cover crop biomass is generally negatively correlated with weed biomass (Balkcom et al., 2016). The need for in‐season weed control remains due to variability in cover crop stand and suppression (Wiggins et al., 2016).…”