Tebuthiuron {N-[5-(1,1-dimethylethyl)-1,3,4-thiadiazol-2-yl]-N,N′-dimethylurea} was evaluated on three Wyoming soil types for control of big sagebrush (Artemisia tridentata Nutt.), silver sagebrush (Artemisia cana Pursh.), and phytotoxic effects on associated vegetation. Big sagebrush was controlled with tebuthiuron at application rates of 0.6 to 1.1 kg ai/ha, whereas silver sagebrush was not completely controlled. Prairie junegrass [Koeleria pyramidata (Cam.) Beauv.], western wheatgrass (Agropyron smithii Rydb. ♯3 AGRSM), needleandthread (Stipa comata Trin. ♯ STDCO), and green needlegrass (Stipa viritdula Trin. ♯ STOVI) were not significantly reduced with tebuthiuron up to 1.1 kg ai/ha. Blue grama (Bouteloua gracilis H.B.K. ♯ BOBGR), downy brome (Bromus tectorum L. ♯ BROTE), plains pricklypear (Opuntia polyacantha Haw. ♯ OPUPO), and broom snakeweed [Gutierrezia sarothrae (Pursh.) Britt. and Rugsby, ♯ GUESA] were tolerant to tebuthiuron at rates up to 1.1 kg ai/ha.
