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Disturbance increases potential for infestation of new areas by weeds such as cheatgrass (Bromus tectorum). Reclamation is implemented in an effort to restore native vegetation, however, cheatgrass often contaminates seed used for reclamation. Because cheatgrass germinates more rapidly and at colder temperatures than many native grasses, it may be possible to remove cheatgrass by exploiting germination differences. We initiated a sequence of experiments where native grass and cheatgrass seeds underwent a wet germination treatment followed by a drying period. We used three cheatgrass populations and six native grass species in four replicates of fifty seeds each. During the first experiment, we evaluated three different germination temperatures (3, 6, and 12°C), for 20-days. We held treatment temperature constant (6°C) in the second experiment and compared four different treatment lengths (8, 10, 12, and 14 days). To evaluate treatment effects on germinabilty, we reinserted all seeds into growth chambers set at optimal temperatures for germination after a 14-day drying period. ANOVA revealed a significant two-way interaction (p < 0.0001) between species and temperature in the first experiment and between species and length of treatment in the second experiment. During the first experiment, cheatgrass germinated earlier and more rapidly than native species at all three temperatures. No cheatgrass survived drying after the 6°C and 12°C treatments. More nontreated seeds germinated compared with treated seeds among all species except blue grama. The 3°C treatment had no effect on the germinability of blue grama seeds. Blue grama germinability was unaffected by treatment duration in the second experiment, and thickspike wheatgrass was only affected by the 14-day treatment. Cheatgrass removal was limited in the second experiment. Our results indicate germination differences may be exploited to reduce cheatgrass contaminants in some native grass species.