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Rangeland weeds are said to have greater economic impact on livestock producers than any other pests, by reducing forage, adversely affecting livestock, or increasing management costs. Some weeds, like the perennial forb Dalmatian toadflax (Linaria dalmatica [L.] Mill.) are invasive and considered noxious in much of the West. In contrast, the native perennial forb Geyer larkspur (Delphinium geyeri Greene) is limited in distribution but associated with high spring cattle mortality where present. Targeted grazing may be used to reduce weed impacts. However, research that evaluates grazing's effectiveness at controlling these two species is limited and sometimes conflicting. Our objectives were to determine effects of targeted sheep grazing on Dalmatian toadflax, Geyer larkspur, and the desirable plant community, and to compare grazing against several herbicide treatments. Ewes grazed in cells containing both target weed species, in four treatments of varying density and timing with stocking rate held constant. We also evaluated two spring herbicide treatments. We measured cover, biomass, and weed density two months after the first treatment and analyzed data with a one-factor ANOVA. All grazing treatments initially reduced larkspur density and then limited regrowth, with larkspur density in herbicide treatments intermediate between grazing treatments and the non-treated check two months after defoliation (p<0.0015). Perennial grass biomass was reduced in most grazing treatments (p=0.0009), whereas cover increased in herbicide treatments (p=0.0013). Immediately after treatment, more than 80% of Dalmatian toadflax stems in all grazing treatments had been impacted, but we detected no treatment effects on any toadflax variables two months after defoliation (p>0.58). These are preliminary results from the first year in a two-year study.