1. Acid deposition and forest decline
2. C. Pyle, M. P. Schafale, and T. R. Wentworth, 1985 : History of Disturbance in Spruce-Fir Forests of the SARRMC Intensive Study Sites- Mt. Rogers National Recreation Area, Black Mountains, and Great Smoky Mountains. SARRMC - Southern Appalachian Spruce-Fir Ecosystem Assessment Project. 67 p.