Herbicide Screening for Seed Forages in Establishment Year

Weed control is critical in the establishment year for forages grown for seed production. With that in mind, in the spring of 2013, we initiated a research trial at the Northeast Agriculture Research Foundation near Melfort, SK to identify herbicides that provide adequate weed control while posing acceptable risk of crop damage for selected forage species. These species included grasses; hybrid bromegrass, timothy, perennial ryegrass, slender wheatgrass and tall fescue as well as forage legumes; red clover, alsike clover, sweet clover, cicer milkvetch and birdsfoot trefoil. A secondary objective was to provide data on herbicide tolerance that can be used to support minor use registrations for herbicides found to have acceptable crop tolerance.

Herbicide treatments were applied in a 4 replicate randomized complete block design, with an untreated check along with a full recommended rate plus a 2X rate (to simulate what might happen where sprayer overlaps occur) for each herbicide by crop combination. On July 4 herbicides were applied to perennial ryegrass, and other grass species were treated July 8, while all forage legume species were treated either July 9 or 10.

Despite rather intense weed competition, we were able to identify numerous crop – herbicide combinations that held potential for minor use registration on nine of the ten forage species evaluated. It should be noted that the data is for a single year at a single site. Under different climatic conditions, crop damage or weed control effectiveness could vary. For this reason, additional crop tolerance trials are needed to validate results obtained to date. In addition to meeting these objectives, we have established additional area to accommodate trials in 2014 on established forages.

For more information about this research project, please click on Research on the website menu and look under Past Research for “Herbicide Screening for Seed Forages in Establishment Year”.