Annual Grass Control in Flax (Linum usitatissimum) with Quizalofop

Abstract

In field experiments over a 3-yr period, quizalofop {(±)-2-[4-[(6-chloro-2-quinoxalinyl)oxy)phenoxy] propanoic acid} at 100 to 150 g ae/ha effectively controlled several annual grass weeds and volunteer barley (Hordeum vulgareL. # HORVX) in flax (Linum usitatissimumL. ‘Linott’). Quizalofop applied when flax was 10 cm tall generally was more effective on wild oats (Avena fatuaL. # AVEFA) and green foxtail [Setaria viridis(L.) Beauv. # SETVI] than when flax was 4 cm tall. Volunteer barley was controlled at both stages of flax growth. Weed interference in untreated plots adversely affected flax quality factors such as seed size, seed weight, percent oil, and iodine value of the oil but not in quizalofop-treated plots.