Evaluation of Three Imidazolinone Herbicides for Control of Yellow and Purple Nutsedge in Woody and Herbaceous Landscape Plants

Foliar-applications of Pursuit applied at 280 and 560 g/ha (4 and 8 oz/A) provided 97% purple nutsedge and 86% yellow nutsedge control at 560 g/ha (8 oz/A). Foliar-applications of Cadre applied at 70 g/ha(1 oz/A) provided 95% purple nutsedge and 61% yellow nutsedge control. Image provided 70 and 77% yellow nutsedge and 56 and 59% purple nutsedge control applied at 430 g/ha (6 oz/A) and 560 g/ha (8 oz/A), respectively. Azalea ‘Macrantha Orange’ was not tolerant to any of the imidazolinone herbicides tested. Likewise, shore juniper exhibited 17 to 35% growth reduction from the imidazolinone herbicides 4 WAT. Juniper growth reductions increased to between 25 and 37% 8 WAT. Redtip photinia was tolerant to Image at 430 and 560 g/ha (6 and 8 oz/A) and Cadre applied at 35 g/ha (0.5 oz/A). Pursuit-treated photinia exhibited 26 to 33% growth reductions 4 WAT. Green liriope was tolerant of all herbicide treatments 4 WAT. Of the 13 bedding plant taxa tested only French marigolds were found tolerant of Pursuit.