ML060940302
| ML060940302 | |
| Person / Time | |
|---|---|
| Site: | Nine Mile Point  |
| Issue date: | 06/06/1997 |
| From: | US Dept of Interior, Fish & Wildlife Service |
| To: | Office of Nuclear Reactor Regulation |
| References | |
| Download: ML060940302 (1) | |
Text
U.S. Fish & Wildlife Service Habitat Why Its Threatened Threatened and Endangered Species American Harts-Tongue Fern (Asplenium scolopendrium var. americanum)
The American harts-tongue fern is a federally threatened species. Threatened species are animals and plants that are likely to become endangered in the foreseeable future.
Endangered species are ani-mals and plants that are in danger of becoming extinct.
Identifying, protecting, and restoring endangered and threatened species is the primary objective of the U.S. Fish and Wildlife Services endangered species program.
This fern is found in close association with outcrops of dolomitic limestone, in coulees, gorges and in cool limestone sinkholes in mature hardwood forests. It requires high humidity and deep shade provided by mature forest canopies or overhanging rock cliffs. It prefers soils high in magnesium.
Although this plant is found over a very wide area, from Alabama to Canada, its populations tend to be very small and isolated due to its unique habitat. Because of its natural rarity, it is particularly vulnerable to disturbance. Many activities threaten the American harts-tongue.
Quarrying, recreation and residential development have all destroyed these plants and their habitat. Canadian populations are threatened by lumbering and the development of land for ski resorts and country estates, among other activities. By removing shade trees, logging raises light levels and lowers humidity, decimating any American harts-tongue ferns in that area.
U.S. Fish & Wildlife Service Endangered Species Division 1 Federal Drive Fort Snelling, Minnesota 55111-4056 612/713-5350 Federal Relay Service 1-800-877-8339 http://midwest.fws.gov/endangered This fern can be found in climates as different as Canada and Alabama, suggesting that it had spread widely since the last ice age.
1997 Photo by A. M. Evans