Sethoxydim for grass control in sugarbeets.
In trials in 1984 at several sites in the Pacific Northwest of the USA and California where the main grass weeds were (a) Echinochloa crus-galli, (b) Avena fatua and (c) Sorghum halepense, Poast (sethoxydim) applied at 0.2 or 0.3 lb a.i./acre to 2-8 inch tall plants of (b) in the Pacific Northwest gave 94 and 98% control, resp. Differences were similar when plants were 13 inches tall. Control achieved with 0.3, 0.4 or 0.5 lb a.i./acre applied in California on the ground or from the air did not differ between methods of application; (a) was present in 5 of 7 trials and was well controlled with the lowest rate, but (c) needed 2 applications with the first at the highest rate. In tank mixture studies using Poast + Betamix (phenmedipham + desmedipham) involving (a), recommended rates of 0.3 + 1.0 lb a.i./acre reduced grass control, which was improved by increasing the Poast rate to 0.4 lb a.i./acre. No damage to sugarbeet was reported.