Agrostis rossiae

Agrostis rossiae, or Ross' bentgrass, is a species of perennial or annual grass that is endemic to the Firehole River drainage and Shoshone Geyser Basin of Yellowstone [National Park]. It is one of 3 endemic plants to the park.

Range

Endemic to the Firehole River drainage and Shoshone Geyser Basin of Yellowstone National Park.

Habitat and ecology

This plant only grows in the thermal water, where the combination of moisture and warmth create a natural greenhouse. Because of warmth of the ground soil, seeds tend to germinate in December or January, producing a green presence in thermal areas by late winter. Flowers tend to emerge in May or June, and by July the plants dead due to the heat from above and below.

Taxonomy

There are possibly two or three species of thermal bentgrasses that may be present in Yellowstone, but more research should be conducted before a taxonomic decision is made.

Conservation

This species is listed a G1 Critically Imperiled by NatureServe, primarily threatened by the encroachment of Agrostis scabra and recreational activities.