Barneby Ridge-cress

Lepidium barnebyanum

Description

Barneby ridge-cress is a perennial that grows to a height of 2-6 in (5-15 cm) and forms raised clumps up to 8 in (20 cm) wide. Smooth, hairless stems rise from a deep, woody taproot; the narrow leaves are clustered at the base of the plant. The four-petaled, cream-colored flowers begin blooming in early May. They are 0.25 in (5-7 mm) across and alternate along a stem that rises 1-2.5 in (2.5-6 cm) above the plant's base. The very small seeds, carried in elliptical seed pods, are dispersed in June and July.

The species was discovered in 1947 and was first described under the scientific name Lepidium montanum ssp. demissum. It has also been known by the common name of Barneby pepper cress.

Habitat

The species is restricted to a single known site in Utah, where it grows on marly shale barrens at an elevation of 6,200-6,500 ft (1,890-1,980 m). Barneby ridge-cress is a member of the shale barren pulvinate (clump-forming) plant community which is part of the broader pinyon pine-juniper woodland community characteristic of the area. It is found in association with other clump forming species including stemless gold-flower (Hymenoxys acaulis), Arenaria hookeri, Townsendia mensana, and Partheniura ligulatum. Other associated plant species include Astragalus spatulatus, Eriogonum batemanii, and Castelleja scabrida.

Distribution

Since it is limited to a single site, the historic range of Barnaby's ridge-cress is the same as its current distribution.

Barneby's ridge-cress is known from a single population with four distinct stands on the Uintah and Ouray Ute Indian Reservation in northeast Utah. These stands are on three ridge lines on both sides of Indian Creek on the northeast margin of Indian Creek Canyon about 3 mi (5 km) south of Starvation Reservoir and the town of Duchesne. The total population is estimated at about 5,000 individuals over an area of less than 500 acres (202.3 hectares). Searches of similar shale barren habitats in the Uinta Basin of northeast Utah and adjacent Colorado have failed to locate additional populations.

Threats

The main threats to Barneby's ridge-cress are disturbances caused by motorcycles and other off-road vehicles, and oil and gas development. Although the Ute Tribe prohibits off-road vehicle use on the reservation, enforcement is difficult. The sole population lies within an oil and gas field where several wells are scheduled to be drilled. The plant grows on the relatively level ridge lines in generally steep terrain. These ridge lines are the preferred routes for off-road vehicles and are likely sites for the construction of roads and the location of wells.

Conservation and Recovery

Two federal agencies are involved in any resource development on the Ute Reservation. The Bureau of Indian Affairs is responsible for assisting the tribe in resource development of reservation lands, and the Bureau of Land Management must approve proposed operations on all leaseholds within the reservation. Both agencies are responsible for ensuring that any land action does not jeopardize the continued existence of Barneby's ridge-cress. A Fish and Wildlife Service recovery plan is expected to recommend ways to deal with the threat of off-road vehicles.

Contacts

Regional Office of Endangered Species
U.S. Fish and Wildlife Service
P.O. Box 25486
Denver Federal Center
Denver, Colorado 80225
http://www.r6.fws.gov/

Utah Ecological Services Field Office
145 East 1300 South, Suite 404
Salt Lake City, Utah 84115-6110
Telephone: (801) 524-5009
Fax: (801) 524-5021

References

U.S. Fish and Wildlife Service. 1989. " Lepidium barnebyanum Supplemental Status Report." Salt Lake City, Utah.

Welsh, S. L. 1978. "Status Report: Lepidium barnebyanum." Brigham Young University Herbarium, Provo, Utah.

Welsh, S. L., N. D. Atwood, S. Goodrich, and L. C. Higgins. 1987. A Utah Flora. Great Basin Naturalist Memoirs, No. 9.