Florida Torreya

Torreya taxifolia

Description

Florida torreya, Torreya taxifolia, is a cone-shaped evergreen conifer that reaches a mature height of 59 ft (18 m). It has whorled branches and stiff needles that emit a pungent, resinous odor when crushed. One common name for this tree is stinking cedar. Dark green, fleshy seeds mature from midsummer to autumn. Pollen cones and ovules grow on separate trees, which reach sexual maturity after about 16 years. Wood from this species has been used in the past for fence posts, shingles, and firewood.

Habitat

Florida torreya is native to the bluffs and ravines of the Apalachicola River Valley. This diverse ecosystem is the only deep river system with head-waters in the southern Appalachian Mountains. When glaciers receded at the end of the last period of glaciation, the bluffs and ravines of this river system maintained cool moist conditions while the surrounding area became drier and warmer. Because of this unique and isolated environment, the torreya and other endemics have attracted the attention of scientists and local plant enthusiasts.

Distribution

Florida torreya was more widespread in the last glacial epoch when the cool, moist conditions in which it thrives were common. Today, it grows in the ravines along the eastern side of the Apalachicola River from Lake Seminole in Georgia to Bristol in Liberty County, Florida. The single Georgia population, on the margins of Lake Seminole, consisted of 27 trees in 1981 and is entirely on public land administered by the U. S. Army Corps of Engineers. A single tree also exists in North Carolina, and is considered the largest and least disease-riddled of the species, perhaps because no other Florida torreyas are nearby.

Florida populations occur on state, city, and privately owned lands. Torreya State Park was established to protect Florida torreya and other endemic species. A city park in Chattahoochee also provides some protected habitat for this species. An isolated population occurs on the margin of Dog Pond which lies to the west of the Apalachicola River.

Threats

The most immediate threat facing Florida torreya is disease. The natural population has been drastically reduced since 1963 by a fungal disease that causes severe defoliation and necrosis of the needles and stems. Trees resprout from the roots but then die before reaching reproductive age. Recent application of fungicides has shown promise for stemming the disease, and cultivated, uninfected specimens from botanical gardens can provide seeds and material for future reintroduction. Extensive research is needed to control disease and develop disease-resistant populations.

Other threats appear momentarily to be in abeyance. In the past, housing developments destroyed large tracts of torreya habitat, but the steepness of the bluffs and ravines precludes further development in the remaining habitat. Dams and reservoirs along the Apalachicola may have taken a toll of trees in the past. A water impoundment project planned near Blountstown, however, is not expected to harm the torreya.

Conservation and Recovery

In 1994, biologists from the North Carolina Arboretum and the U. S. Fish and Wildlife Service Asheville Office collected cuttings and a seedling from the largest surviving Florida torreya tree. This tree, planted on a North Carolina farm in the 1800s, is well outside the species' native range in the Florida panhandle and in Decatur County, Georgia. Though all of these wild populations have been decimated by a fungal disease, the North Carolina tree is one of the few remaining disease-free specimens. Although there are no other specimens within several hundred miles or kilometers, the North Carolina tree has produced fertile seeds at least once, and seedlings are now growing around it. The seedling collected from this tree was planted in a disease-free environment on the Arboretum grounds. The cuttings will be rooted and cultivated at the Arboretum to preserve the tree's genetic material.

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

Alfieri, S. A., Jr., A. P. Martinez, and C. Wehlburg.1967. "Stem and Needle Blight of Florida Torreya." Proceedings of the Florida State Horticultural Society 80:428-431.

Butler, W. 1981. "Status of the Florida Torreya inGeorgia." Report. The Georgia Protected Plants/Natural Areas Program, Atlanta.

Godfrey, R. K., and H. Kurz. 1982. "The Florida Torreya Destined for Extinction." Science 138:900-901.

U. S. Fish and Wildlife Service. 1986. "Florida Torreya Recovery Plan." U.S. Fish and Wildlife Service, Atlanta.