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The Great Basin covers approximately 49.2 million hectares and spans from the Columbia Plateau to the Mohave Desert and from Wasatch Mountains to the Sierra Nevadas. Within this region the invasive annual grass Bromus tectorum has caused a shift in the fire-regime, resulting in reduced burn intervals. Post-fire restoration efforts have focused on establishing native perennial grasses, forbs, and shrubs to increase competition and reduce B. tectorum population. Pseudorogenia spicata (bluebunch wheatgrass) is a drought tolerant steppe system bunch-grass frequently used in restoration projects; however, fall seeding events have a reported germination occurrence of 80% within sub-optimal winter conditions. Winter germination timing leads to greater pathogen susceptibility, premature exhaustion of seed resources (carbohydrates), drought stress and predation, thereby increasing seeding failure. The plant hormone abscisic acid is reported to prolong seed dormancy and has the potential to mitigate seeding failure due to sub-optimal germination timing. I propose a study to determine the efficacy of seeds enhanced with ABA across the Great Basin. Five study sites will be selected from the eastern (Rush Valley & Santaquin, UT), central (two in Great Basin National Park), and northern (Steen Mountain, OR) districts of the Great Basin. Cultivars of P. spicata will be coated with varying levels of ABA and planted in randomized blocks at each site. Germination bags will be randomized across the blocks and retrieved monthly for non-structural carbon, ABA levels, and germination and viability assessments.� I hypothesize that cultivars of P. spicata, augmented with ABA, will exhibit prolonged dormancy traits similar to the natural after-ripening and dormancy of local seed, enhancing seedling establishment and survival.