Relict Trillium

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Relict Trillium

Trillium reliquum

Status	Endangered
Listed	April 4, 1988
Family	Liliaceae (Lily)
Description	Herbaceous perennial with S-curved stems and light green to brownish purple flowers.
Habitat	Moist hardwood forests.
Threats	Development, herbicides, fire, and livestock grazing.
Range	Alabama, Georgia, South Carolina

Description

An herbaceous perennial, the relict trillium, or Trillium reliquum, is distinguished from other sessile-flowered trilliums by its decumbent or S-curved stems, its distinctively shaped anthers, and the shape of its leaves. Flowers appear in early spring in a variety of colors, complicating identification. Flowers are often light green or brownish purple but are sometimes pure yellow. The fruit is an oval-shaped, berry-like capsule, which matures in early summer. Like other members of its genus, this tuberous plant dies back to its rhizome after the fruit matures.

Habitat

Relict trillium is found primarily in undisturbed, moist hardwood forests, where soils are rich in organic matter, but otherwise vary in structure from alluvial sands to rocky clays. Plants are sometimes found along the edges of rights-of-way for roads, sewer, and power lines.

Distribution

Relict trillium was recognized as a distinct species in 1975, and the historic range of the species has not been determined. It is currently found at 21 sites: four in Alabama, 14 in Georgia, and three in South Carolina.

A site in Henry County, Alabama, consisting of about 150 plants in 1988, is managed by the Army Corps of Engineers but suffers from dumping and recreational traffic. A privately owned site in Lee County, Alabama, supports several thousand plants distributed over 120 acres (55 hectares). A privately owned site in Bullock County, in undisturbed woodland (threatened by future logging) hosts about 1,000 plants. Another Bullock County site hosts several thousand plants on partially logged woodland.

In Georgia, Clay County is home to six sites, with population numbers ranging from as few as 90 plants to more than 1,000 plants, depending on the location. Lee County is home to two populations, one of about 100 plants, and the other of several hundred plants, both on privately owned land. Macon County has two populations, one of around 100 plants, and another of around 75 plants. Early County has one population of around 30 plants on privately owned land, considered highly disturbed (it was hit by a tornado in 1985). Columbia County has two populations, one of several thousand plants (on undisturbed, privately owned, woodland) and the other of around 50 plants on privately owned, disturbed woodland. Talbot County has one population of 20 plants on land owned by the Georgia Department of Natural Resources. Most sites are in the proximity of development, logging, or quarrying activities.

By far, the largest known population of relict trillium is found in Aiken and Edgefield Counties, South Carolina, where some 50,000-100,000 plants are scattered along bluffs and ravines bordering the Savannah River and several of its tributaries. A portion of this population falls within a state nature preserve and another section falls within a city park. Despite the size of this population, only 500 of the plants were protected as of 1990, in a natural area purchased by the South Carolina Wildlife and Marine Resources Department. Aiken County has an additional population of several thousand plants in groups scattered over 10 acres (4 hectares) of private land; Edgefield County also hosts another population of 20,000 plants on privately owned woodland interspersed with agricultural land.

Threats

While the relict trillium is not threatened with immediate extinction, encroaching residential development, utility line construction and maintenance, logging, and an aggressive introduced vine, have extirpated whole populations. Most population sites are adjacent to rapidly expanding urban centers that have claimed large swaths of habitat. Other historic sites have been overrun by Japanese honeysuckle, which covers the ground in mats and smothers underlying vegetation. In recognition of this threat, the South Carolina Wildlife and Marine Resources Department initiated a honeysuckle control program on the preserve supporting the species. Another introduced vine, the kudzu, is also aggressively replacing the native flora in some areas.

Conservation and Recovery

Relict trillium is informally listed as an endangered species in Alabama, but it is accorded no legal status or protection. State authorities, however, have pledged to monitor populations, regulate logging, and control the growth of honeysuckle at state-owned sites. While some private landowners in Alabama have pledged to protect plants on their property, one of the largest colonies is on land already subdivided into lots for development.

The Natural Heritage Programs in Alabama, Georgia and South Carolina, along with the U. S. Fish and Wildlife Service (FWS) and the Nature Conservancy, have contacted most of the owners of relict trillium populations. Ultimately, the FWS must enlist the cooperation of private landowners in the conservation effort. Acquiring sections of habitat to serve as preserves or transplanting the species to protected areas may also be considered.

The 1991 species recovery plan from the FWS calls for the delisting of the species by 2001 if funds are available and recovery actions are adequate and complete. Among the actions needed to delist the species are the provision of interim protection; species studies; required management activities; maintenance of cultivated populations and store seeds; and the reestablishment of populations. The recovery plan also calls for an increase in public awareness of the species through education and public information programs; the enforcement of conservation laws; and the assessment of recovery efforts.

The species will be considered for delisting when there are 12 self-sustaining populations (two in Alabama, seven in Georgia and three in South Carolina) that are protected to the degree that the species no longer qualifies for federal listing as endangered. Although this is less than the total number of populations currently in existence, it is believed that it will provide the number of populations needed to insure the continued existence of the species. It should also be noted that at least 10 of the extant populations contain fewer than 200 individuals each. Upon completion of the biological studies required by the recovery plan the recovery criteria will be reevaluated and changed if necessary.

Contact

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