In-Season and Carry-Over Effects of Cover Crops on Productivity and Weed Suppression
Abstract
Data necessary to evaluate cover crop multifunctionality are lacking, particularly for cool, short-season cropping niches typical of northern New England. We quantified cover crop biomass, weed suppression, and carry-over effects on subsequent crop and weed growth in 12 winter cover crop treatments {monocrops and mixtures of annual ryegrass [Lolium multiflorum Lam.], winter rye [Secale cereale L.], alfalfa [Medicago sativa L.], crimson clover [Trifolium incarnatum L.], white clover [T. repens L.], hairy vetch [Vicia villosa Roth], soybean [Glycine max (L.) Merr.], and forage radish [Raphanus sativus L.], and a weedy fallow [control] treatment}. The forage radish treatments (11 and 28 kg ha–1 seeding rates) were among the highest producers of fall cover crop biomass in all 4 site-years. The forage radish treatments were also among the most weed-suppressive in the fall, reducing weed biomass relative to the weedy fallow treatment by 89 to 97% in each of the 4 site-years. In the spring, annual ryegrass was among the highest (ranging from 349–571 g m–2 across site-years) and alfalfa was among the lowest (39–287 g m–2) biomass-producing treatments in 3 out of 4 site-years. Weed biomass in the spring was 73 to 99% lower in annual ryegrass, hairy vetch, and hairy vetch–winter rye mixture treatments than in the weedy fallow treatment. Biomass of the sorghum [Sorghum bicolor (L.) Moench]–sudangrass [S. sudanense (Piper) Stapf] phytometer was higher following white clover, hairy vetch, the hairy vetch–rye mixture, and both forage radish treatments compared to following annual ryegrass.
Publication Date
5-6-2016
Journal Title
Agronomy Journal
Publisher
ACSESS (Alliance of Crop, Soil, and Environmental Science Societies)
Digital Object Identifier (DOI)
Scientific Contribution Number
2655
Document Type
Article
Rights
Copyright © 2016 by the American Society of Agronomy, Inc.
Recommended Citation
Hodgdon, E. A., N. D. Warren, R. G. Smith, and R. G. Sideman. 2016. In-Season and Carry-Over Effects of Cover Crops on Productivity and Weed Suppression. Agron. J. 108:1624-1635. https://dx.doi.org/10.2134/agronj2015.0419