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Seeding of native grasses in the Great Basin is perilous and developing improved germplasm has been a research priority for decades. Limitations are the criteria by which “improved” has been defined. All improvements (ex: forage production) hinge on an assumption of establishment. This research examines how improvements relate to establishment. Bottlebrush squirreltail is a native perennial grass that has been studied extensively for rangeland rehabilitation potential. Squirreltail is a good candidate for plant material development because of phenotypic variation and known hybridization. We have had little rehabilitation success with germplasm releases. In 2009, we began searching for squirreltail populations in degraded Wyoming big sagebrush rangelands of the northwestern Great Basin. By 2011, we identified 3 unique phenotypes. Type 1: exhibits rapid seedling growth and pubescent leaves. The pubescence gives a silvery appearance. Type 2: exhibits colder temperature germination, a characteristic attributed to the success of cheatgrass. Type 3: exhibits a small leave surface almost needle-like, similar to drought tolerant needle grasses. We hypothesized seeding success ranking as Type 1 (vigor), Type 2 (cold germination) and Type 3 (leaf morphology). To test this hypothesis we seeded the 3 phenotypes along with a popular release germplasm (Toejam) at five sites (8” pricip) and designed a common garden soil box test to reduce external field variables. Field studies indicated that Type 1 and 3 were equally successful. Soil boxes determined Type 1 the most successful, partially supporting our hypothesis. All three phenotypes established well above the cultivated ‘Toejam' and within the range of providing cheatgrass suppression (Type 1- 9.64 plants/m2, Type 2- 9.43/m2, Type 3- 7.71/m2 and Toejam – 0.36/m2). Establishment, though promising, was based on first year July seedling counts and continued die-off is expected. The true test of success is the sustainability of plant densities, cheatgrass suppression and future seedling recruitment.