Great Basin Naturalist


Quadrat and propagule trapping studies were made on the moraine of the Schoolroom Glacier and in adjacent dry alpine meadow vegetation in the Teton Range in 1978–1979. Forty-six species of vascular plants were collected. Distributionally, three groups of species exist. One of these is concentrated primarily on the moraine, a second in the meadow, and the third in a narrow ecotonal band at the base of the distal slope of the moraine. The moraine slopes are steep and unstable, with vegetation cover ranging from 1 to 9 percent, dominated by Cirsium tweedyi (Rydb.) Petr. Along the more stable moraine crest the vegetation cover is heavier, and is similar to that in the meadow. The meadow vegetation cover is about 50 percent, dominated by Astragalus kentrophyta Gray. Using a combination of cover and frequency as a measure of importance, dominance-diversity curves were constructed for the moraine and meadow. Both approach geometric series, which are suggested as indicating harsh environments. Abiotically pollinated species are more successful on the moraine than biotically pollinated species, but the reverse is true for the meadow. Propagule trapping studies suggest that dispersal of anemochorous propagules onto the moraine is very low compared with dispersal in the meadow.