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Dalmatian toadflax (Linaria dalmatica [L.] Mill.) is an invasive weed of northeast and western North American rangelands known for displacing desirable communities and reducing forage, particularly following disturbance. Managers typically use herbicides to manage toadflax populations and prevent spread. This experiment was designed to complement a separate study comparing herbicide with targeted sheep grazing. Our objective was to evaluate Dalmatian toadflax control with four herbicides alone and in combination, at the same rates, applied in either fall or spring. We applied herbicides in late fall 2013 and late spring 2014. Fall treatments generally reduced toadflax cover better than spring treatments in 2014 (P < 0.0001). In midsummer 2015, 21 months after treatment (MAT; fall application) and 13 MAT (spring application), chlorsulfuron+aminocyclopyrachlor reduced toadflax biomass by 80% compared with the check (P = 0.07). Fall treatments, irrespective of herbicide, reduced toadflax density and increased perennial grass biomass compared to spring treatments (P < 0.03). Treatments containing aminopyralid resulted in the greatest perennial grass biomass (P < 0.0001). Where cheatgrass was abundant prior to treatment, herbicides that reduced toadflax were associated with cheatgrass biomass increases as high as 400% (P < 0.0001). Managers should consider recovery potential of an invaded site prior to vegetation treatments. Where perennial grass recovery is likely, fall treatments may provide most consistent toadflax control with the least desirable species damage. Chlorsulfuron+aminocyclopyrachlor provided best control in our study while retaining perennial grass biomass similar to the non-treated check.