Effects of invasive plants and pollen limitations on seed set of Eriogonium visheri
The rare endemic plant, Eriogonum visheri A. Nelson is restricted to badlands formations in the northern Great Plains. It had been known from fewer than 100 locations in Montana, North Dakota, and South Dakota prior to a study at Badlands National Park in 2003-4 that added 65 new locations within the park. Conservation of E. visheri has therefore become a management goal for the park. As an annual plant inhabiting a stressful environment, adequate pollination and seed set is important. Invasive plants, notably Melilotus officinalis (L.) Lam. and Salsola tragus L. , commonly co-occur and flower concurrently with E. visheri, so assessing their effects on pollination and seed set is key to protecting the rare endemic. In addition, a congener, E. pauciflorum, flowers throughout the summer and may provide an important alternative resource for pollinators shared with E. visheri, which flowers for only a short period in mid-summer. The goal of this study is to quantify relative effects of E. pauciflorum and the two invasive species on pollination and seed set of E. visheri.
Diane L Larson