Germinability of Seed Reserves in a Big Sagebrush Community

We investigated seasonal variation in germinability of seed reserves in a degraded big sagebrush (Artemisia tridentataNutt.) community. A bioassay was employed to determine germinability. There were many more germinable seeds and seedling establishment was greater under the shrub canopies than in the interspace. Caryopses of downy brome (Bromus tectorumL.) were the most abundant of any species in the litter where most of the seeds were located. Seasonal germinability of downy brome caryopses depends on the environment of the seedbed when the samples were collected and on the incidence of environmentally-induced dormancy or on loss of dormancy.