Riparian vegetation in the southern Appalachian mountains (USA) following chestnut blight

• Published in: Forest ecology and management 2002, Vol.155 (1), p.97-106
• Main Authors: Vandermast, D.B, Van Lear, D.H
• Format: Article
• Language: English
• Subjects: American chestnut; Animal and plant ecology; Animal, plant and microbial ecology; Biological and medical sciences; Demecology; Forest management. Stand types and stand dynamics. Silvicultural treatments. Tending of stands. Natural regeneration; Forestry; Fundamental and applied biological sciences. Psychology; Plants and fungi; Regeneration; Rhododendron; Rhododendron maximum; Riparian vegetation; Southern Appalachians; Stand types and stand dynamics. Silvicultural treatments. Tending of stands. Natural regeneration; Succession; USA, Southeast
• ISSN: 0378-1127; 1872-7042
• DOI: 10.1016/S0378-1127(01)00550-3

American chestnut is often listed as an important component of mesic midslopes and xeric ridges in pre-blight southern Appalachian forests, but its former importance in riparian forests has generally been considered minor. To document its importance in riparian forests, 589 American chestnut stumps were located on four sites (two previously logged, two unlogged) in the Blue Ridge physiographic province of the southern Appalachians. Diameters and basal areas of chestnut were calculated and compared among sites and to basal area (BA) of live trees. Chestnut BA ranged between 8.4 and 12.4 m 2/ha (25 and 40% of current BA). Vegetative composition on 58 random plots suggests that three community types were represented on the four study sites: (1) old-growth forest with sparse rhododendron; (2) logged forest with sparse rhododendron; and (3) forest dominated by rhododendron which controlled vegetative composition regardless of logging status. Thickets of ericaceous shrubs that developed after the blight were significantly denser in logged forest than in old-growth. Only shade-tolerant herbs such as galax and partridge-berry, as well as a rare orchid, Appalachian twayblade, were found growing in rhododendron thickets. Results of our study suggest that the gap-phase hypothesis, where species diversity is maintained in cove forests of the southern Appalachians through gap-phase disturbance, should be modified to allow for dynamics influenced by rhododendron. The reintroduction of periodic fire into southern Appalachian riparian habitat may control rhododendron dominance and improve tree regeneration.