Kral's Water-plantain

Sagittaria secundifolia

Description

An aquatic, perennial herb, Kral's water-plantain arises from a stiff, elongated rhizome up to 4 in (10.2 cm) in length. This plant can float above or below the water. The shape of its leaves depends upon the velocity and depth of its habitat. In swift shallows, the leaves are linear, rigid, sickle shaped, and 2-3 in (5.1-7.6 cm) long. In deep and quiet waters, the leaves are more quill-like, being longer, linear in shape, and tapered. Separate male and female flowers are produced on a stalk 4-20 in (10.2-50.8 cm) long. The petals are inconspicuous in the female flowers; however, in the male flowers, they are white and 0.4-0.6 in (1-1.5 cm) in length.

Habitat

Kral's water-plantain typically occurs on frequently exposed shoals or rooted among loose boulders in quiet pools up to 3.2 ft (1 m) in depth. Where suitable habitat exists, plants grow in pure stands or in association with various submergents (below-water plants), including pond-weed and water-milford. Some emergent (above-water) associates are smartweed, false pimpernels, and water-willow. The immediate banks are often dominated by thickets of shrubs including alder, wild azalea, mountain laurel, fetter-bush, and holly. Sphagnous seeps are frequent, with Carex, beak rush, pipe wort, panic-grass, yellow-eyed grass, and meadow beauty among the common genera present. The stream bottoms are typically narrow and bounded by steep slopes. Two endangered plants—the green pitcher plant and Harperella —and three candidate plants occur in associated habitats at several sites.

Distribution

Restricted to the Little River Drainage System on Lookout Mountain, this plant is known from a total of 12 sites in northeast Alabama and northwest Georgia. The 12 populations are scattered over approximately 25 river mi (40.2 km). Eight of these populations are in pools or rivers with partial canopy coverage, and these all support only five to 40 plants. The other four populations, located on shallow shoals, had 75 to several hundred plants each. Historically, Kral's water-plantain was also known from Town Creek in the Sand Mountain area of northeast Alabama, but this population has been extirpated.

Threats

A major threat to this species is the elimination or adverse modification of its already limited habitat. Clearing of the adjacent river banks for development, surface mining, or agricultural purposes poses a significant threat. These activities contribute to water quality degradation and increase stream turbidity and siltation from erosion. Similar impacts probably caused the loss of the population and much of the suitable habitat in the Town Creek watershed. The Little River population may be adversely affected by eutrophication from garbage dumping and leaking sewage systems. This eutrophication increases the presence of filamentous algae, which cling to individual plants. Extreme water turbidity and dense filamentous algae decrease the amount of light available to the plants for growth and flowering.

A small number of sites are used as fords and are often a center for recreational activity, subjecting them to damage by off-road vehicle traffic.

Approximately 33% of the existing Little River habitat and populations will be destroyed if a proposed hydroelectric plant is constructed. In addition to flooding several local populations and changing stream flow dynamics, the construction of this facility would cause excessive siltation and further degrade water quality.

This species is clonal and primarily asexual, which suggests low genetic variability. To reproduce sexually, which increases genetic variability, the species needs shallow shoals that are open to direct sunlight. Only four of the twelve existing populations are located in areas conducive to flowering. In fact, flowering has been observed in only one out of a hundred plant clones.

Conservation and Recovery

Approximately 40% of the habitat in Little River is owned by the Alabama Power Company and 20% by the Alabama Department of Conservation and Natural Resources. The remainder is in private ownership within Alabama and Georgia.

Alabama's Desoto State Park personnel are aware of Kral's water-plantain in the park and are committed to protecting the plant along with other natural resources. Park personnel are working with the Dekalb County office of the Alabama Department of Health to sample water at various points within the Little River watershed to document any pollution that may exist and, if found, to determine the cause and take corrective action. They are also working to have the waters of the Little River within the state park designated Outstanding Natural Resource Waters. Such a designation would help to justify maintenance of high quality aquatic habitat within the park, consistent with applicable state and federal requirements.

The Georgia Department of Natural Resources is aware of this species in Georgia and is monitoring it through the department's Freshwater Wetlands and Heritage Inventory program.

Contacts

U. S. Fish and Wildlife Service
Regional Office, Division of Endangered Species
1875 Century Blvd., Suite 200
Atlanta, Georgia 30345
(404) 679-4000
http://southeast.fws.gov/

Jackson Ecological Services Field Office
6578 Dogwood View Parkway, Suite A
Jackson, Mississippi 39213-7856
Telephone: (601) 965-4900
Fax: (601) 965-4340

References

Kral, R. 1982. "A New Phyllodial-Leaved Sagittaria (Alismataceae) from Alabama." Brittonia 34: 12-17.

Kral, R. 1983. "A Report on Some Rare, Threatened, or Endangered Forest-Related Vascular Plants of the South." U.S. Department of Agriculture, Forest Service, Technical Publication R8-TP2. 1305 p.

Norquist, Cary. 1990. Personal Communication.Ecological Services Field Office, Jackson, Mississippi.

U. S. Fish and Wildlife Service. 13 April 1990. "Threatened Status for Sagittaria secundifolia (Kral's water-plantain)." Federal Register 55 (72): 13907-13911.

Whetstone, R. D. 1988. "Status Survey of Sagittaria secundifolia. " Provided under contract to the U.S.Fish and Wildlife Service. Southeast Region, Atlanta, Georgia. 28 pp. and attachments.