Great Basin Naturalist


The colonization of the pocket-gopher (Thomomys talpoides) mounds by annual and perennial species of the understory of aspen woodland was observed over a four-year period. New and old gopher mounds exist as a mosaic of sites in one of three surface conditions: bare, dominated by annuals with a few seedlings of perennials, and dominated by perennials with annuals in peripheral areas. The regular creation of these new sites for plant colonization appears to favor the maintenance of aggressive perennials at high densities in the understory vegetation.