Efficacy of Imiflex, Zest, and Assure II on Green Foxtail Control

Grass weeds pose a serious management challenge in grain sorghum. Recent development of three herbicide-tolerant sorghum technologies such as Inzen, Igrowth, and DoubleTeam will provide the opportunity for producers to use nicosulfuron (Zest), imazamox (Imiflex), quizalofop-p-ethyl (FirstAct) grass weed control, respectively. The main objectives this research were (1) determine effectiveness Imiflex applied preemergence (PRE) on green foxtail control comparison commonly used group 15 herbicides; (2) compare efficacy Zest, Imiflex, Assure II early- or late-POST at two different rates; (3) tank-mix compatibility II, Select Max (clethodim) with 2,4-D (Weedar 64) dicamba (Clarity) control. Field experiments conducted fallow ground natural infestation Kansas State University Agricultural Research Center Hays, KS. PRE herbicide programs, including Dual Magnum, Warrant, Outlook tested. tested late-postemergence (POST) timings. early POST treatments alone tank-mixture Weedar 64 and/or Clarity also separate study. Among both rates provided an excellent (89 94%) up 50 days after (DAPRE), whereas did not exceed more than 51% any herbicides. 10 fl oz/a 95% 28 (DAEPOST). Green (6 oz/a) was moderate ranged from 77 83% DAEPOST. late inadequate 14 31% 21 (DALPOST). In study, tank-mixing reduced by >50% compared treatment. These results suggest that 9 can residual activity season foxtail. Furthermore, higher rate effective foxtail; however, significantly decline if is tank-mixed Clarity.