Quackgrass Control in Established Alfalfa with Sethoxydim
Field studies were conducted during 1990 and 1991 in northeast South Dakota to determine the effect of sethoxydim application timing on quackgrass [Elytrigia repens (L.) Nevski] control in established alfalfa (Medicago sativa L.). Sethoxydim was applied as single applications in the fall, spring, after the second cut of alfalfa or as various repeated applications in the fall, spring, and after the first and second cuts of alfalfa. The alfalfa-quackgrass mixture was harvested three times per year, and dry matter yields of alfalfa, quackgrass, and total herbage were determined. Total herbage samples were analyzed for crude protein (CP) concentration. Usually, single application of sethoxydim in either the fall or spring did not control quackgrass as well as multiple applications. However, three and four applications of sethoxydim per year did not consistently control quackgrass any better than two applications per year. Sethoxydim reduced quackgrass yields in most instances, but yields and CP concentrations of total herbage were seldom affected. Use of sethoxydim for quackgrass control in established alfalfa may be warranted only in situations where relatively weed-free forage is desired.
Canadian Journal of Plant Science
DOI of Published Version
Twidwell, E. K.; Kephart, K. D.; and Clay, Sharon, "Quackgrass Control in Established Alfalfa with Sethoxydim" (1994). Agronomy, Horticulture and Plant Science Faculty Publications. 265.