Tebuthiuron was evaluated at two Wyoming locations for its effects on big sagebrush control and associated vegetation, Big sagebrush was controlled with tebuthiuron at 0.6 to 1.1 kg ai/ha. Green needlegrass, prairie junegrass, blue grama, and Douglas rabbitbrush were unaffected by tebuthiuron treatments. Western wheatgrass and downy brome increased at different study locations and were dominant grass species at the end of 7 yr.