INVESTIGATING TRENDS IN PLANT SPECIES AND SOIL CHARACTER IN THE BIGHORN BASIN OF WYOMING

Floral species are often characterized by adaptations that allow survival in harsh environments. The Bighorn Basin of north-central Wyoming is an arid plateau located between four mountain ranges, creating a rain shadow effect resulting in low levels of precipitation. Common species of flora are distinctive to the region. Furthermore, a wide range of discrete soil characters is found in the basin as the complete Paleozoic and Mesozoic sedimentary record of northwestern Wyoming is exposed within the basin. Are there trends between identifiable floral species and the soil character and underlying bedrock? The goal of this study was to test whether gypsum-rich soils host vegetation different than gypsum-poor soils in the region. For this field study conducted in July 2023, we logged 1,035 species waypoints within and around the Sheep Mountain Anticline. Each waypoint marks the location of an identifiable plant, as well as notes about the soil color, composition, and texture. A total number of 20 different floral species were observed. Waypoints are projected on geologic maps of the area to visualize possible relationships between plant species, soil character, and bedrock. Initial observations suggest that there are several floral species limited to sulfate and iron-rich soils associated with the Permian Goose Egg Formation and Triassic Chugwater Group. These species include Halogen glomeratus (common name: saltlover), Oenothera caespitiosa (common name: tufted English primrose), and Oreocarya thyrsiflora (common name: calcareous crypthantha). Such relationships between plants and soils have implications for understanding bedrock weathering, soil habitability, and inferring underlying rock type, as well as mapping from satellite imagery.