Use of a Rolled-rye Cover Crop for Weed Suppression in No-Till Soybeans

Abstract

Cover crop management with a roller/crimper might reduce the need for herbicide. Weed suppression from a rolled cereal rye cover crop was compared to no cover crop with and without postemergence herbicide application in no-till soybean. The experiment was designed as a two-way factorial with rye termination and soybean planting date as the first factor and weed control treatment as the second. Cereal rye was drill-seeded in late September and managed using glyphosate followed by a roller/crimper in the spring. Soybean was no-till seeded after rolling and glyphosate was applied postemergence about 6 wk after planting to half the plots. Rye biomass doubled when delaying rye kill by 10 to 20 d. Weed density and biomass were reduced by the rye cover crop in all site–location combinations except one, but delaying rye kill and soybean planting date only reduced both weed density and biomass at a single location. The cover crop mulch provided weed control similar to the postemergence herbicide in two of four locations. Treatments did not affect soybean grain yield in 2007. In 2008, yield at Landisville with rye alone was equal to those yields receiving the postemergence herbicide, whereas at Rock Springs, it was equivalent or less. The net added cost of a rye cover crop was $123 ha−1with or $68.50 ha−1without a postemergence herbicide application. A rolled-rye cover crop sometimes provided acceptable weed control, but weed control alone did not justify the use of the cover crop. The potential for reduced herbicide use and other ecosystem services provided by a cover crop justify further refinement and research in this area.

Impact of Cover Crop Management on Level of Weed Suppression: A Meta‐Analysis

“…For example, rye biomass increased by 37 to 100% when terminated 10 to 14 d after the normal early rye termination date, with subsequent increases in weed suppression (Mischler et al, 2010;Mirsky et al, 2011;Nord et al, 2012). Indeed, delaying termination would allow for more biomass accumulation, which is essential for weed smothering by the cover crop residues.…”

Weed Control Using Conventional Tillage, Reduced Tillage, No-Tillage, and Cover Crops in Organic Soybean

“…Conditions for weed emergence were more favorable due to reduced mulch soil coverage and less cover crop biomass in 2015 (Table 2). Mischler et al [41] observed high weed control efficacy, similar to a post-emergence herbicide application, when using rye as cover crop mulch at Rock Springs and Landisville, PA, USA in 2007. Liebl et al [9] presented similar results for a four-year study on soybeans and cover crops in Urbana, IL, USA.…”

Short- and full-season soybean in stale seedbeds versus rolled-crimped winter rye mulch

“…In southern Wisconsin, weed biomass in early July was reduced by 62% in rye mulch compared with stale seedbeds 12 . In central Pennsylvania, mid-summer weed biomass reduction in soybean due to rolled and crimped winter rye compared with bare soil across five site-years was 15, 53, 91, 92 and 93% 18 . Lastly, in the absence of herbicides, rolled and crimped rye in Alabama provided 58, 69 and 83% weed control over 3 years 16 .…”