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ARS Home » Southeast Area » Auburn, Alabama » Soil Dynamics Research » Research » Publications at this Location » Publication #412019
Research Project: Agronomic and Engineering Solutions for Conventional and Organic Conservation Agricultural Systems in the Southeastern U.S.

Location: Soil Dynamics Research

Title: Impact of cover crops and their termination timing on weed management in corn

Author
item KUMAR, VIPIN - Virginia Polytechnic Institution & State University
item SINGH, VIJAY - Virginia Polytechnic Institution & State University
item FLESSNER, MICHAEL - Virginia Polytechnic Institution & State University
item REITER, MARK - Virginia Polytechnic Institution & State University
item KUMARI, ANNU - Auburn University
item Price, Andrew
item KUHAR, THOMAS - Virginia Polytechnic Institution & State University
item Mirsky, Steven

Submitted to: Weed Technology
Publication Type: Peer Reviewed Journal
Publication Acceptance Date: 4/13/2025
Publication Date: N/A
Citation: N/A

Interpretive Summary: A study was conducted to evaluate the effect of four cover crops species and their termination timings on cover crop biomass accumulation, weed control, and corn yield. A field experiment evaluated wheat, cereal rye, hairy vetch, and rapeseed, with four termination timings; 28 days before planting corn (DBP), 14, 5, and 1 DBP as a sub-plot factor. No cover crop-no till (NC-NT) and no cover crop-tilled (NCT) were used as check treatments. Hairy vetch produced most biomass (4.11 and 5.92 t ha-1) among cover crop species, followed by cereal rye (3.71 and 5.06 t ha-1), wheat (3.47 and 4.27 t ha-1), and rapeseed (1.83 and 3.31 t ha-1) in 2021 and 2022, respectively. At 28 days after preemergence (PRE) herbicide applications, hairy vetch provided 67 and 70% greater control of small-seeded broadleaf (SSB) and large-seeded broadleaf (LSB) weeds, respectively, compared with NC-NT. Corn yield was 16% greater in hairy vetch plots as compared to NC-NT, whereas yield was 20% lower in rapeseed plots. Across termination timings, 14 DBP treatment had 12% greater corn yield, while 1 DBP treatment had 15% lower corn yield as compared to NC-NT.

Technical Abstract: A study was conducted to evaluate the effect of four cover crops species and their termination timings on cover crop biomass accumulation, weed control, and corn yield. A field experiment was arranged in a split-plot design where cover crop species; wheat, cereal rye, hairy vetch, and rapeseed were treated as a main plot factor, with four termination timings; 28 days before planting corn (DBP), 14, 5, and 1 DBP as a sub-plot factor. No cover crop-no till (NC-NT) and no cover crop-tilled (NCT) were used as check treatments. Hairy vetch produced most biomass (4.11 and 5.92 t ha-1) among cover crop species, followed by cereal rye (3.71 and 5.06 t ha-1), wheat (3.47 and 4.27 t ha-1), and rapeseed (1.83 and 3.31 t ha-1) in 2021 and 2022, respectively. Regression analysis of cover crop biomass with growing degree days (GDD) indicated that each 100 unit increase in GDD can increase biomass of cereal rye, wheat, hairy vetch, and rapeseed by 0.88, 0.67, 0.78, and 0.62 t ha-1, respectively. At 28 days after preemergence (PRE) herbicide applications, hairy vetch provided 67 and 70% greater control of small-seeded broadleaf (SSB) and large-seeded broadleaf (LSB) weeds, respectively, compared with NC-NT. Cover crops tested in the study, did not vary for summer annual grass (SAG) and sedge (SED) control. Among termination timings, 5 and 1 DBP provided greater SAG, SSB, and LSB control as compared to 14 and 28 DBP. All cover crops and termination timings were statistically similar for weed control at 28 days after post-emergence herbicide application. Corn yield was 16% greater in hairy vetch plots as compared to NC-NT, whereas yield was 20% lower in rapeseed plots. Across termination timings, 14 DBP treatment had 12% greater corn yield, while 1 DBP treatment had 15% lower corn yield as compared to NC-NT.