Native grassland restorations are often unsuccessful as a consequence of unreliable seed sources and competition from weeds and agronomic species. To improve on conventional approaches, we tested whether native hay can be used as a seed source for restoring native mixedgrass prairie on oil and gas well sites and associated disturbed areas. We also assessed the recovery of grassland that had been cut to harvest native hay. We assessed three wellsites seeded with native hay seven years earlier to evaluate longer term recovery, and they showed significant similarity to controls in adjacent grassland. Additionally, in 2012, five wellsites and an access road were seeded with native hay cut from grassland close to the sites. Grassland cut for native hay recovered within one year, showing similar species composition. In the second year, native hay restored wellsites had significant weedy annual cover; nevertheless, native grasses and forbs germinated, particularly needle grasses, wheatgrasses, and bluegrasses. Three of the native hay restored wellsites were sprayed with a non-selective herbicide in the third year; however, the remaining sites showed good recovery in the third year, with native grasses replacing most of the original weedy species. Collectively, results from this research suggest seeding from native hay is a successful and sustainable technique for restoring native vegetation cover and diversity on industrial disturbances in native grasslands.