Small's Milkpea

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Small's Milkpea

Galactia smallii

StatusEndangered
ListedJuly, 18, 1985
FamilyLeguminosae (Fabaceae)
DescriptionSlender vine with compound leaves and pinkish flowers.
HabitatPine rockland; pine scrub vegetation, poorly developed limestone soils.
ThreatsUrbanization, competition with introduced plants.
RangeFlorida

Description

Small's milkpea is a slender vine with compound leaves, usually with three elliptic leaflets about 0.8 in (2 cm) long. Pinkish flowers bear petals.67 in (1.7 cm) long. Plants root in limestone crevices and spread out across the ground.

Small's milkpea has also been classified as Galactia prostrata.

Habitat

This plant grows in poorly developed sandy soils over a porous limestone substrate in Florida pine rockland. Pine rockland habitat is unique to the South Florida Limestone Ridge, a rocky upland area extending from Broward County to Long Pine Key in Everglades National Park. The ridge is rarely raised more than 16 ft (5 m) above the surrounding marshes and wet prairies. It provides a unique habitat, supporting a variety of plants that are found nowhere else.

Distribution

Pine rockland vegetation, including Small's milk-pea, was once widely distributed along the 63 mi (105 km) South Florida Limestone Ridge. Pine rockland habitat formerly extended over 152,000 acres (61,500 hectares) between metropolitan Miami on the east and the Everglades on the west.

This species is currently found at only two sites, both near Homestead (Dade County), Florida. Probably fewer than 100 plants survive.

Threats

It is estimated that up to 98% of the Dade County pine rockland habitat has been destroyed by the expansion of metropolitan Miami. Remnant habitat (about 8,150 acres or 3,300 hectares) is fragmented and suffers from the suppression of fire, which is needed periodically to renew the habitat. Pine rockland that is not periodically burned succeeds to hardwood hammock vegetation, which shades out plants such as Small's milkpea.

Invasion of exotic plants is also affecting the pinelands and specifically the milkpea. Two introduced species, Brazilian pepper (Schinus terebinthifolius ) and a large reed (Reynaudia reynaudiana ), inhabit the same ecological niche and compete directly with milkpea for water and nutrients.

Conservation and Recovery

Habitat preservation, controlled burning, and removal of introduced species are the keys to recovering Small's milkpea and other plants endemic to the pine rockland. Developmental pressures, however, are almost irresistible. The last fragments of pine rockland habitat in good condition, perhaps 1,700 acres (690 hectares), are imminently threatened by development.

Contact

U.S. Fish and Wildlife Service
Regional Office, Division of Endangered Species
1875 Century Blvd., Suite 200
Atlanta, Georgia 30345-3319
Telephone: (404) 679-4159
Fax: (404) 679-1111
http://southeast.fws.gov/

References

Austin, D. F., P. Krauss, et al. 1980. "Endangered and Threatened Plant Species Survey in Southern Florida." Contract Report #14-16-0004-79-106.U.S. Fish and Wildlife Service, Atlanta.

Herndon, A. 1981. "Galactia smallii : A New Name for Galactia prostrata Small." Rhodora 83:471-472.

Herndon, A. 1984. "Dade County Pinelands." Palmetto 4 (2): 3-11.

U.S. Fish and Wildlife Service. 18 July 1985. "Determination of Endangered and Threatened Status for Five Florida Pine Rockland Plants." Federal Register 50 (138): 29345-29349.