Big Sagebrush Control with Tebuthiuron

Abstract

Tcbuthiuron (20% a.i. pellets) was applied h 2 years at rates of 0.25,0.5,1.0, and 2.0 kg a.i./ha on sagebrush-grass range. Mortality of big sagebrush (Artedsiu tridentata) and herbaceous yield was measured at the end of the second growing season, posttreatment. Mean mortality increased with increasing herbicide rate to 93.9% at 2 kg a.i./ha. Herbaceous yield decreased with increasing herbicide rate to a mean of 177.3 kg/ha at the 2 kg .i./ha rate contrasted to a mean of 423.9 kg/ha for the control. Big sagebrush (Artemisia tridentata) is easily controlled with 2,4-D at rates of 1.0 to 2.0 kg a.i./ ha (Hyder and Sneva 1955). Tebuthiuronl [ l-(5-tert-butyl-l,3,4-thiadiazol-2-yl)-l,3-dimethylurea] can effectively control sagebrush at rates of 2 kg a.i./ ha (Britton and Sneva 1981). The objectives of this study were to evaluate the effectiveness of tebuthiuron at rates of 2 kga.i./ ha and less in controlling big sagebrush and subsequent effects on herbaceous yield.