Restoring Crested Wheatgrass Stands to Big Sagebrush for Improved Sage-Grouse Habitat: A Literature Review

Abstract

Greater sage-grouse (Centrocercus urophasianus) is a high priority species for federal and state land management agencies in the Western United States. Sage-grouse are sagebrush (Artemisia spp.) obligates requiring sagebrush for their survival throughout the year. Sagebrush has been removed and replaced with crested wheatgrass (Agropyroncristatum & A.desertorum) throughout the West. The objectives of this paper were to review the literature (100 papers), as well as consult experts, to determine which methods are most likely to eliminate crested wheatgrass and establish sagebrush. No technique eliminates crested wheatgrass in a single application but research suggests it should not comprise more than 14% cover for successful reseeding of other species. Grazing and fire have no long-term impacts on crested wheatgrass. Mechanical treatments, such as plowing, disking, and cultivating reduce and eradicate crested wheatgrass, but a flush of invasive annual grasses following mechanical disturbance can make establishment of seeded species difficult. If invasive plant establishment is a problem with mechanical treatments, crested wheatgrass stands should be treated with glyphosate in early spring for two consecutive years at a rate of 1.1 kg/ha of active ingredient. Then, sagebrush should be seeded in the late fall using a compact row seeder or Brillion cultipacker at a rate of 0.22 kg/ha pure live seed.