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Using seeding to restore degraded rangelands of the northern Great Plains is a major challenge.� Often, seeded species fail to establish and areas remain/become dominated by annual bromes and other unwanted plants.� In this study, we used herbicides and reseeding to address fields at two coal mines that had become dominated by annual bromes after initial seeding efforts failed.� Of particular interest was big sagebrush, among the species most difficult to restore to our mixed grass prairie study system.� To avoid herbicide damage to big sagebrush and other seeded species, we applied a nonselective herbicide (glyphosate) prior to seeding or an herbicide that exclusively controls grasses (quizalofop) after seeding.� We also combined the two herbicides to determine if both together outperformed either alone.� Consistently across four experiments (2 seeding years � 2 mines), annual brome cover was 22%(13%, 36%) in the control, compared to 11%(5%, 25%) and 16%(7%, 35%) in glyphosate and quizalofop plots, respectively.� Combining herbicides did not decrease annual brome cover below glyphosate alone.� The second summer after seeding, seeding without herbicides increased big sagebrush densities from 0.15(0.03, 0.60) to 0.76(0.27, 2.11) plants m-2�at Decker and from 0.02(0.004, 0.11) to 0.11(0.03, 0.43) plants m-2�at Spring Creek [mean(95% CI)].� Combining glyphosate with seeding increased big sagebrush densities to 3.05(1.42, 6.56) plants m-2�at Decker and to 0.43(0.13, 1.40) plants m-2�at Spring Creek.� Quizalofop did not have lasting positive effects on big sagebrush densities.� In addition to big sagebrush, seeding increased other seeded species, but herbicide effects on these species were inconsistent.� Herbicides can provide a window of opportunity for establishing big sagebrush.