Background
Authored By: J. D. Waldron, R. N. Coulson, D. N. Cairns, C. W. Lafon, M. D. Tchakerian, W. Xi, K. D. Klepzig, A. Birt
SPB and HWA are two very different forest-damaging insects that inhabit host tree species, which exploit opposite ends of the moisture gradient found in the Southern Appalachian Mountains (Figure on the right), although they occasionally occur together at either end of their natural range. We choose these insects to illustrate the utility of LANDIS in investigating forest insect threats because they represent the extreme cases of an indigenous pest that has the potential to cause great damage (SPB) and an invasive pest that has the potential to remove an entire host plant species from eastern forests (HWA).
Subsections found in Background
- Southern Pine Beetle Case : In the Southern Appalachian Mountains, xeric slopes and ridges have historically been dominated by yellow pines (Pinus spp.).
- Hemlock Wooly Adelgid Case : Eastern hemlock (Tsuga canadensis) and Carolina hemlock (Tsuga caroliniana) appear in mesic flats, draws, ravines, coves, and canyons of the Southern Appalachian Mountains.
Encyclopedia ID: p3315
