beargrass plant

National Park Service

Several times throughout the Lewis and Clark journals, the writers refer to a plant they named beargrass. This common wildflower (Xerophyllum tenax) is actually not a grass, but a member of the family.

The plant is native to Montana, but can also be found in subalpine meadows and coastal mountains throughout the Pacific Northwest, extending from British Columbia to northern California and eastward to Alberta and northwestern Wyoming.

Beargrass can grow up to five feet in height with long and wiry, grass-like basal leaves at the base of the stalk and a cluster of small, dense white flowers at the top. While bears do not eat the plant, they will use leaves as denning material. Sheep, deer, elk, and goats are known to eat beargrass.

A common myth states that beargrass only blooms every seven years. In reality, the plant flowers whenever conditions are appropriate. A single plant may have numerous basal rosettes on a common root system. Each rosette will bloom only once. Factors for abundant plant blooming include ideal amounts of spring rainfall and moisture present in the soil. For this reason, back-to-back blooming is rare. Blooming can begin in late May in lower elevations and continue into August in the high country.

The plant was first called beargrass by members of the Lewis and Clark expedition. At that time "Bear grass" was a common name for yucca (commonly called soapweed today), which has a superficial resemblance to beargrass. Native peoples have used beargrass leaves for basket weaving, and roots were used to treat injuries. Other common names for this plant include basket grass, bear lily, pine lily, elk grass, squaw grass, and turkeybeard.

Lewis & Clark National Historic Trail

Last updated: August 20, 2018