Bradshaw's Lomatium

Lomatium bradshawii

Description

Bradshaw's lomatium, or desert-parsley, Lomatium bradshawii, an herbaceous perennial, grows from a long, slender taproot. Stems are erect, up to 26 in (65 cm) tall. Leaves are deeply dissected into narrow, pin-nate segments. Light yellow flowers, grouped into a ragged cluster (umbel) at the ends of the stems, bloom in April and May. Fruits mature by early July.

Habitat

This plant is a constituent of the native prairie lowland community of Oregon. It grows in low swales close to streams or lakes in areas that remain moist for most of the year. Prairie habitats are maintained by periodic grass fires. In the prolonged absence of fire, weedy and shrubby plants invade, crowding out prairie-adapted species.

Distribution

This plant was once abundant in the Willamette Valley of Oregon, from Salem to Creswell through parts of Benton, Linn, Lane, Polk, and Marion counties.

Bradshaw's lomatium has been reduced to small remnant populations, scattered from Stayton to just south of Eugene. Ninety percent of known plants are found within a 10-mi (16-km) radius of Eugene, Oregon. Populations vary in size from thousands to only a few plants, and the vigor of individual plants varies considerably.

The largest population, in the West Eugene Wet-lands, numbered about 25,000 plants in 1993; it is located near Willow Creek in a diverse plant community that is a remnant of native bottomland prairie. This parcel of land also harbors the rare Willamette daisy (Erigeron decumbens var. decumbens ). The parcel has been leased by the Nature Conservancy to preserve the habitat.

A second large population, numbering perhaps 10,000 individuals, occurs near the Fern Ridge Reservoir on land administered by the Army Corps of Engineers. As of 1993, two remnant populations survived near Corvallis on the Finley National Wildlife Refuge at the Jackson-Frazier Preserve (totaling about 2,500 plants). An adjoining, privately owned portion of the latter population was destroyed in 1980 by a housing development. About 200 plants were discovered near Mt. Pisgah in 1985, a site also threatened by urban and agricultural development.

Threats

The loss of native prairie habitat to agriculture has been the most significant factor in the overall decline of Bradshaw's lomatium across its range. Remaining populations are threatened by the expanding urban environs of Eugene, Oregon. In 1995, for instance, in Eugene's public Amazon Park—several acres of which are habitat for Bradshaw's desert-parsley—the Eugene Track Club provided funding and labor to install lighting around a popular jogging path, but, unfortunately, inadvertently used unauthorized equipment and caused damage to several areas known to contain Bradshaw's lomatium. The U.S. Fish and Wildlife Service (FWS), the Emerald Chapter of the Native Plant Society of Oregon, and city personnel met on-site and agreed to cooperate in establishing a Conservation Agreement, in which the city promised to conduct a comprehensive native plant survey and wetland delineation within the entire park, and to create a management plan for native wet prairie and woodland remnants.

Two of the plants' larger populations are specifically threatened by residential and industrial development. Recovery efforts focus on land and easement acquisition to protect remaining prairie lands.

Conservation and Recovery

The Bureau of Land Management manages a population northwest of Eugene along the Long Tom River. In the past, much of this tract was leased for agriculture to the detriment of the plant. New management practices, including controlled burning, should improve the vigor of this population.

The Nature Conservancy, Army Corps of Engineers, the FWS, and Bureau of Land Management all own land with populations of Bradshaw's lomatium, and are managing the sites in order to promote the species' long-term survival. All of these agencies are in the process of developing plans for protection of the plants on their lands, and these plans were incorporated into the 1993 Recovery Plan for the species.

The Recovery Plan outlines the recovery strategy for Bradshaw's lomatium. The first task is to ensure the protection of sites by acquisition, conservation easement, or management agreement to prevent their destruction from rural, urban or industrial development. The second task is management of protected sites to assure long-term survival of the plants' populations.

The plant will be downlisted (from Endangered to Threatened), according to the Recovery Plan, when ten populations are protected and managed as necessary to assure their continued existence. For the purposes of the plan, a viable population includes at least 2,000 flowering plants occupying at least 20 acres (8 hectares) of secure habitat, with population structure indicating stable or increasing plant numbers.

Contact

Regional Office of Endangered Species
U.S. Fish and Wildlife Service
Eastside Federal Complex
911 N.E. 11th Ave.
Portland, Oregon 97232
http://pacific.fws.gov/

References

Kagan, J. S. 1980. "The Biology of Lomatium bradshawii, a Rare Plant of Oregon." Report. U.S. Fish and Wildlife Service, Portland.

U.S. Fish and Wildlife Service. 1993. "Recovery Plan for Bradshaw's Lomatium." U.S. Fish and Wildlife Service, Portland.