Technical Abstract: Basalt milkvetch or threadstalk milkvetch (Astragalus filipes Torr. ex A. Gray) is a perennial legume that is widely distributed on rangelands in western North America and holds promise for rangeland revegetation and restoration programs. No germplasms or cultivars are commercially available for basalt milkvetch. Seeds of 67 accessions (20 accessions from the Northern Basin and Range Ecoregion) were collected in 2003 from the western USA. Accessions evaluated at Providence and Millvile in northern Utah in 2005 and 2006 varied significantly (P<0.01) for biomass yield, plant height, number of stems, number of inflorescences, and plant vigor score. Accessions did not vary (P>0.01) for crude protein concentration at Providence, whereas seed yield and seed mass varied significantly (P<0.01) at Millville. Analysis of field-collected forage samples from the 20 accessions from the Northern Basin and Range Ecoregion indicated that four accessions had detectable levels of selenium, swainsonine, and/or nitrotoxins. Twelve accessions from the Northern Basin and Range Ecoregion with the highest seed yields and with no detectable levels of selenium, nitrotoxins, and swainsonine were identified. Seed collected from the respective wildland collection sites for these 12 selected accessions was bulked by equal weight to form the G0 generation of NGR-1 Germplasm, which was cooperatively released by USDA-ARS and the Utah Agricultural Experiment Station as NBR-1 Germplasm Basalt Milkvetch. NBR-1 Germplasm is a selected class, manipulated track pre-variety germplasm for use in restoration, reclamation, and rehabilitation of semiarid rangelands in the northern Great Basin Region of the western USA.