Cover crops in a Wisconsin annual cropping system: Feasibility and yield effects

Abstract

Corn (Zea mays L.), soybean [Glycine max (L.) Merr.], and wheat (Triticum aestivum L.) are important components of crop rotations in southern Wisconsin. Cover crops can protect soil and water in these systems. This study examines cover crop treatments in various crop sequences of these cash crops to determine effects on crop yield. Cover crops seeded following corn or soybean included cereal rye (Secale cereale L.) or oat (Avena sativa L.), which were either drilled after harvest, broadcast into the senescing crop, or drilled in alternating rows. Species planted after wheat included red clover (Trifolium pretense L.) or berseem clover (Trifolium alexandrinum L.), either frost seeded or drilled postharvest, as well as oat and rye drilled postwheat harvest in alternating rows. Broadcast seeding cereal rye preharvest into senescing soybean had the most successful establishment following corn or soybean. The system with the most consistent cover crop growth was winter-hardy species established preharvest. However, this system decreased corn yield 5.8-8.6%. All other cover crop treatments had no effect on yield, but other postcorn or soybean treatments had limited growth. The highest yield for corn was observed following soybean, while soybean had the greatest yield when all three crops were present. Wheat yields were not affected by frost seeding or by rotation. This multiyear trial confirms the expected challenges of establishing cover crops in corn-soybean rotations in southern Wisconsin, while winter wheat provided clearer opportunities for cover cropping. Cover crop research in corn-soybean systems need to address the corn yield declines caused by cover crops.

Forage Radish Cover Crops Improve Soil Quality and Fruit Yield of Lycium barbarum L. in an Arid Area of Northwest China

“…In the Argentine Pampas, maize yield was reduced by 8% under non-legume cover cropping and increased by 7% under legume cover cropping compared with fallow controls [40]. In Wisconsin, USA, cover cropping resulted in a 6-9% reduction in maize yield [41]. In our study, cover cropping with a moderate level of organic fertilizer substantially increased L. barbarum yield.…”

Recent cover crop adoption is associated with small maize and soybean yield losses in the United States

“…In reviewing experiments in North America, for example, Marcillo and Miguez ( 2017 ) reported that maize yields, on average, were unaffected by cover crops, but results varied widely based on the type of cover crop, the level of fertilization, and the date of cover crop termination. In contrast, Malone et al ( 2022 ) found maize yield reductions of 6%–9% when cover crops were established successfully in the US state of Wisconsin. In experiments in the Argentinean Pampas, maize yields were reduced by 8% when following a non‐legume cover crop compared with a fallow control but increased by 7% when following a legume cover crop (Alvarez et al, 2017 ).…”

Short-Term Agronomic and Economic Responses to the Adoption of Cover Crops for Corn Rotation in the Brazilian Semiarid Region

“…One reason for the efficiency of legumes lies in their ability to establish symbiotic relationships with diazotrophic bacteria, which provide atmospheric N to the system through biological nitrogen fixation [3]. Additionally, CCs with low water availability (<500 mm) cover the soil surface, reducing erosion and evapotranspiration rates [5,30].…”