Cooley's Meadowrue

Thalictrum cooleyi

Description

Cooley's meadowrue, Thalictrum cooleyi, is an herbaceous perennial. Stems, rarely exceeding 39 in (1 m) in height, arise from an underground rhizome. The stems stand erect in full sun; in the shade they are lax and sometimes lean on other plants or trail along the ground. Leaves vary considerably in shape, from narrowly lanceolate and unlobed to ovate with two or three lobes. Flowers are borne in an open cluster (panicle). Petals are lacking, but sepals are yellowish to white with lavender filaments. Winged, single-seeded fruits mature in August and September.

Habitat

This plant grows on neutral soils in moist to saturated bogs and in savannah-like clearings in woodlands. Required habitat conditions are typically maintained by periodic fires that remove encroaching woody plants.

Distribution

Considered endemic to the Southeastern Coastal Plain, meadowrue was found historically from North Carolina south to Florida.

Twelve populations of Cooley's meadowrue survive in Brunswick, Columbus, Onslow, and Pender counties, North Carolina, and from Walton County, Florida. Eleven sites in North Carolina support a total of about 800 plants. As of 1990, fewer than 20 plants were known to survive at the single Florida site, which was clear-cut by a commercial timbering operation.

All population sites are privately owned, including one Pender County site that is owned and managed by The Nature Conservancy.

Threats

According to botanists, Cooley's meadowrue is one of the rarest and most directly threatened plant species in the United States. Suppression of fire throughout the range is thought to have been a factor in the overall decline. At least six historic populations have been lost to conversion of habitat to agricultural or silvicultural uses. Remaining populations are threatened by drainage of wetlands, highway construction, and marl pit mining. The plant's localized pattern of distribution and low numbers magnify the severity of current threats.

Conservation and Recovery

As a first step in conservation, the U. S. Fish and Wildlife Service has notified all involved parties and landowners of the location and importance of protecting and managing remaining tracts of habitat. Further recovery measures will depend on the cooperation of landowners, and on the informed actions of road maintenance crews, construction workers, and other land management workers who need to be educated about protecting this rare species.

Contact

Regional Office of Endangered Species
U.S. Fish and Wildlife Service
1875 Century Blvd., Suite 200
Atlanta, Georgia 30345
http://southeast.fws.gov/

References

Leona rd, S. 1987. "Inventory of Populations of Thalictrum cooleyi and Its Occurrence Sites in North Carolina." Report. North Carolina Natural Heritage Program, Raleigh.

Mansber g, L. 1985. " Thalictrum cooleyi : Draft Global Element Ranking Form Prepared for the Nature Conservancy." North Carolina Natural Heritage Program, Raleigh.

Rome, A. 1987. " Thalictrum cooleyi : Draft Steward-ship Abstract." The Nature Conservancy, Arlington, Virginia.