![]() ![]() By the 1980s, reproductively mature Fraser fir trees had experienced 67 percent mortality throughout the species’ range, including 91 percent mortality in Great Smoky Mountains National Park (Dull et al. Within a few years, the infestation spread from the centrally located Black Mountains to all the other populations: Roan Mountain and Mount Rogers by 1962, the Great Smoky Mountains and Grandfather Mountain by 1963, and the Balsam Mountains by 1968 (Amman 1966, Dull et al. Introduced into the northeastern United States in the early 1900s, probably on imported nursery stock, the adelgid was first detected on Mount Mitchell in the Black Mountains in 1957, but may have been present in the area as early as 1940 (Eager 1984). Since that time, however, the balsam woolly adelgid (BWA) has inflicted severe mortality on old-growth Fraser fir forest. 1988), poor management practices were no longer a serious concern by the 1950s. With nearly all the Southern Appalachian spruce-fir forest now occurring on public lands (Dull et al. 1988), reduced the forest type across all elevations from 17,910 hectares to 13,370 hectares (Pyle 1984). Log- ging and fire in the Great Smoky Mountains, which encompass nearly three-fourths of all Fraser fir-red spruce forest (Dull et al. Failed regeneration caused by logging-site degradation may have reduced the extent of the highest spruce-fir forests, those above 1,670 meters, to less than half their former historical area, from 14,277 hectares to 6,881 hectares (Saunders 1979). ![]() Since the late nineteenth century, logging and slash fires have dramatically reduced the distribution of Fraser fir and red spruce in the Southern Appalachians (Pyle 1984, Pyle and Schafale 1988, Saunders 1979). Much of the distri- bution of fir shifted north, following the retreating ice into Canada, New England, and the Northern Appalachians the fir species now occurring in those areas is balsam fir ( Abies balsamea Miller), which is closely related to Fraser fir. By 8,000 years ago, warming climate conditions eliminated lower-elevation spruce-fir stands in the Southeast. At the full-glacial maximum, this boreal forest may have covered 1.8 million km 2 from Mis- souri to the Carolinas (Delcourt and Delcourt 1984). These populations are relicts of a boreal forest that extended across much of the Southeast during the peak of the most recent late-Wisconsin glacial period, from 18,000 years to 12,500 years before present (Delcourt and Delcourt 1987, Whitehead 1973, Whitehead 1981). Whitetop Mountain in Virginia, near Mount Rogers, has red spruce but no Fraser fir. Additionally, three minor populations exist in North Carolina: the Plott Balsams, Cataloochee Balsam, and Shining Rock. It exists in six major island-like populations ( Figure 1): the Great Smoky Mountains in North Carolina and Tennessee the Black Mountains, the Balsam Mountains, and Grandfather Mountain in North Carolina Roan Mountain on the Tennessee/North Carolina border and Mount Rogers in Virginia. In natural Fraser fir stands, this economically and ecologically important conifer occurs almost entirely above 1,300 meters, usually in association with red spruce ( Picea rubens Sarg.), but it becomes the dominant tree species above about 1,800 meters (Busing et al. It has also posed problems for North Carolina’s $100 million annual Christmas tree industry, which relies almost entirely on plantation-grown Fraser fir. During the last 50 years, this exotic invader from Europe has decimated mature natural stands of Fraser fir ( Abies fraseri Poir.), causing significant changes to the spruce-fir ecosystem. Currently, the most serious threat to its continued existence, however, is an insect that measures less than a millimeter in length – the balsam woolly adelgid ( Adelges piceae Ratz.). Never very extensive, this forest type has been reduced by poor forest management practices, and could face elimination as a result of global climate change. ![]() high-elevation red spruce-Fraser fir forests of North Carolina, Tennessee, and Virginia together encompass a unique boreal ecosystem endemic to the southeastern United States. ![]()
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