Post emergence control of Liriope spicata.
A greenhouse experiment was conducted to determine the efficacy of post-emergence spray applications of 7 herbicides (each at 2 rates, oz/acre) for control of L. spicata potted into 3.8 l containers: sulfometuron (1 and 2), metsulfuron (1 and 2), imazapic (6 and 12), imazapyr (32 and 64), 2,4-D (43 and 67), dicamba (16 and 32), and glyphosate (85 and 171). At 30 days after treatment (DAT), only metsulfuron at both rates and sulfometuron at the higher rate had greater injury than the non-treated control. All other treatments had injury similar to the non-treated control. At 60 DAT, both rates of metsulfuron, both rates of imazapyr, and the higher rate of glyphosate had significantly injury greater than that of the non-treated control. The maximum control (91%) as determined by dry weight reduction at 63 DAT was obtained with metsulfuron at 2 oz/acre. Metsulfuron at 1 oz/acre provided 84% control. All other treatments except dicamba at both rates provided some degree of control, although less control than the metsulfuron treatments. Control of foliage regrowth at 90 DAT was consistent with both injury ratings and with dry weight reduction. Metsulfuron application at both rates had similar foliar regrowth control (97%=low rate) (100%=high rate). Imazapyr had similar control for foliar regrowth at both the low rate (85% control) and the high rate (86%). Lower control percentages were found in both rates of sulfometuron, imazapic, and the high rate of glyphosate. The remaining treatments of dicamba, low rate of glyphosate, and 2,4-D were all comparable to the non-treated control. Root tissue control at 90 DAT again showed that metsulfuron was the most effective. Metsulfuron at 1 and 2 oz/acre controlled root tissue by 66 and 80%, respectively. Glyphosate at high rate provided 61% control. All other treatments were similar to the non-treated control.