december_web

Minor Use Registration For The Use Of Stellar™ XL on Grass Seed Crops in Western Canada

By Calvin Yoder, Forage Seed Specialist, PRFSA/SARDA Ag Research

This project started in 2019, and was funded jointly by the Peace Region Forage Seed Growers Association, the Saskatchewan Forage Seed Development Commission, the Manitoba Forage Seed Association, Corteva Agriscience Canada and the Prairie Pesticide Minor Use Consortium. This initiative would not have been successful without the cooperation of, and expertise made available by, the Pest Management Centre through the Canadian Pest Management Priority Setting Workshop, and the Pest Management Regulatory Agency.

In this project, we wanted to focus on the use of a single herbicide. We looked at Stellar™ XL, which is a herbicide sold by Corteva Agriscience Canada that has been available for use in cereal crops in Western Canada for a number of years. Multiple trials were conducted by SARDA Ag Research, AAFC Beaverlodge, Saskatchewan Forage Seed Development Commission and Manitoba Forage Seed Association showed seedling and established grass seed crops had good tolerance to Stellar™ XL. The active ingredients florasulam, fluroxypyr and MCPA ester in Stellar™ XL have satisfactory tolerance when applied to many different seedling or established turf and grass seed crops.

Stellar™ XL has been used on grass seed crops for several years but is now labelled for post-emergent control of annual broadleaf weeds in seedling and established Crop Group 17 forage grasses grown for seed production in the Prairie Provinces and the interior of British Columbia. Crop Group 17 forage grasses include bromegrasses (smooth, meadow and hybrid), fescues (creeping red, tall and meadow), meadow foxtail, orchardgrass, redtop, reed canarygrass, ryegrasses (annual and perennial), timothy and wheatgrasses (crested, slender etc).

Stellar™ XL has proven to be quite effective on many of the weeds present in grass seed fields. When we first started working with Stellar™ XL it was felt it would mainly be effective for weed control on seedling grass stands. Field experience has shown good results for weed control in established grass seed crops as well, and no tolerance issues have been reported to date.