The history of the Black Mountains in North Carolina and the southern Spruce-Fir ecosystem has been fraught with widespread forest decline since the mid 1960’s. Balsam Woolly Adelgid attacks and acidic deposition were two of the most recognized causes of decline. Uncertainty arose about the future of these forests, and projections were made regarding the endangerment or extinction of the endemic Fraser fir ([Pursh] Poiret). This study ana lyzed data sets from a permanent plot network in the Black Mountains dating 1985, 2002, and 2012. Indications that the Fraser fir population is stabilizing from a “boom-bust” cycle of population growth and has entered the stem exclusion stage of forest stand development are evident. Fir live stem density increased more than 250% from 1985 to 2002, and then declined 40% by 2012 at the highest elevations in the forest. Overall, fir appeared to be more impacted on western facing slopes than eastern ones. The population of red spruce experienced a steady decrease in live stem counts, but an increase in live basal area through all years, and at all elevation classes (1675 m, 1830 m, and 1980 m), indicating a normal progression through stand development. Red spruce was also most negatively impacted on western facing slopes. Live stem density was significantly higher (P < 0 .001) than eastern plots, but live basal area was similar between the two aspects. Atmospheric deposition concentrations of the four main acidic molecules at Mt. Mitchell all peaked in 1998, but decreased by 2012. These reductions, occurring shortly after tightened regulations in the 1990 amendments to the Clean Air Act may have potential implications for increased forest resilience.
KeywordsSouthern Spruce-FirBalsam Woolly AdelgidForest Stand DevelopmentForest ResponseForest RegenerationAtmospheric DepositionForest Decline
H. Oostings and W. Billings, “A Comparison of Virgin Spruce-Fir Forest in the Northern and Southern Appalachian System,” Ecology, Vol. 32, 1951, pp. 84-103. http://dx.doi.org/10.2307/1930974
S. A. Cain, “Pollen Analysis of Some Buried Soils, Spartanburg County, South Carolina,” Bulletin of the Torrey Botanical Club, 1944 pp. 11-22. http://dx.doi.org/10.2307/2481484
M. F. Buell, “Late Pleistocene Forests of Southeastern North Carolina,” Torreya, Vol. 45, 1945, pp. 117-118.
P. S. White, “The Upland Forest Vegetation of the Second College Grant, New Hampshire,” Ph.D. Dissertation, Dartmouth College, Hanover, 1976.
C. V. Cogbill and P. S. White, “The Latitude-Elevation Relationship for Spruce-Fir Forest and Treeline along the Appalachian Mountain Chain,” Vegetatio, Vol. 94, No. 2, 1991, pp. 153-175. http://dx.doi.org/10.1007/BF00032629
R. Whittaker, “Vegetation of the Great Smoky Mountains,” Ecological Monographs, Vol. 26, No. 1, 1956, pp. 1-80. http://dx.doi.org/10.2307/1943577
G. H. La Roi, “Ecological Studies in the Boreal Spruce-Fir Forests of the North American Taiga. I. Analysis of the Vascualr Flora,” Ecological Monographs, Vol. 37, No. 3, 1967, pp. 229-253. http://dx.doi.org/10.2307/1948439
C. F. Speers, “The Balsam Wooly Aphid in the Southeast,” Journal of Forestry, Vol. 56, No. 7, 1958, pp. 515-516.
R. G. Hollingsworth and F. P. Hain, “Balsam Woolly Adelgid Effects on Wood and Bark Structure of Fraser Fir and Silver Fir,” Environmental Entomology, Vol. 21, No. 5, 1992, pp. 1103-1109.
C. W. Dull, “Evaluation of Spruce and Fir Mortality in the Southern Appalachian Mountains,” Department of Agriculture, Forest Service (USFS), Southern Region, USA, 1988.
G. F. Smith and N. S. Nicholas, “Patterns of Overstory Composition in the Fir and Fir-Spruce Forests of the Great Smoky Mountains after Balsam Woolly Adelgid Infestation,” American Midland Naturalist, Vol. 139, No. 2, 1998, pp. 340-352. http://dx.doi.org/10.1674/0003-0031(1998)139[0340:POOCIT]2.0.CO;2
C. D. Oliver, “Forest Development in North America Following Major Disturbances,” Forest Ecology and Management, Vol. 3, 1981, pp. 153-168.
N. S. Nicholas, S. M. Zedaker and C. Eagar, “A Comparison of Overstory Community Structure in Three Southern Appalachian Spruce-Fir Forests,” Bulletin of the Torrey Botanical Club, Vol. 119, No. 3, 1992, pp. 316-332. http://dx.doi.org/10.2307/2996764
L. Pitelka and R. Dudley, “Forest Decline and Acidic Deposition,” Ecology, Vol. 70, No. 1, 1989, pp. 2-10.
J. M. Skelly, “A Closer Look at Forest Decline: A Need for More Accurate Diagnostics,” In: P. D. Manion and D. Lachance, Eds., Forest Decline Concepts, American Pathological Society Press, St. Paul, 1992, pp. 85-107.
N. S. Nicholas and S. M. Zedaker, “Ice Damage in Spruce-Fir Forests of the Black Mountains, North Carolina,” Canadian Journal of Forest Research, Vol. 19, No. 11, 1989, pp. 1487-1491. http://dx.doi.org/10.1139/x89-226
R. T. Busing and E. F. Pauley, “Mortality Trends in a Southern Appalachian Red Spruce Population,” Forest Ecology and Management, Vol. 64, No. 1, 1994, pp. 41-45. http://dx.doi.org/10.1016/0378-1127(94)90125-2
D. R. Peart, N. S. Nicholas, S. M. Zedaker, M. M. MillerWeeks and T. G. Siccama, “Condition and Recent Trends in High Elevation Red Spruce Populations,” In: C. Eager, and M. B. Adams, Eds., Ecology and Decline of Red Spruce in the Eastern United States, Springer-Verlag, New York, 1992, pp. 125-191.
R. I. Bruck, W. P. Robarge and A. McDaniel, “Forest Decline in the Boreal Montane Ecosystems of the Southern Appalachian Mountains,” Water, Air, and Soil Pollution, Vol. 48, No. 1, 1989, pp. 161-180.
K. L. Webster, I. F. Creed, N. S. Nicholas and H. V. Miegroet, “Exploring Interactions between Pollutant Emissions and Climatic Variability in Growth of Red Spruce in the Great Smokey Mountains National Park,” Water, Air, and Soil Pollution, Vol. 159, No. 1, 2004, pp. 225-248. http://dx.doi.org/10.1023/B:WATE.0000049179.26009.7f
P. T. Moore, H. V. Miegroet and N. S. Nicholas, “Relative Role of Understory and Overstory in Carbon and Nitrogen Cycling in a Southern Appalachian Spruce-Fir Forest,” Canadian Journal of Forest Research, Vol. 37, No. 12, 2007, pp. 2689-2700. http://dx.doi.org/10.1139/X07-115
K. A. Koo, B. C. Patten and I. F. Creed, “Picearubens Growth at High Versus Low Elevations in the Greast Smoky Mountains National Park: Evaluation by Systems Modeling,” Canadian Journal of Forest Research, Vol. 41, No. 5, 2011, pp. 945-962. http://dx.doi.org/10.1139/x10-243
V. K. Saxena, R. E. Stogner, A. H. Hendler, T. P. DeFelice and R. Y. Yeh, “Monitoring the Chemical Climate of the Mt. Mitchell State Park for Evaluation of Its Impact on Forest Decline,” Tellus, Vol. 41, No. 1, 1989, pp. 92-109. http://dx.doi.org/10.1111/j.1600-0889.1989.tb00128.x
D. S. Kim and V. P. Aneja, “Chemical Composition of Clouds at Mt. Mitchell, North Carolina, USA,” Tellus, Vol. 44, No. 1, 1992, pp. 41-53. http://dx.doi.org/10.1034/j.1600-0889.1992.00004.x
F. P. Hain and F. H. Arthur, “The Role of Atmospheric Deposition in the Lattudinal Variation of Fraser Fir Mortality Caused by the Balsam Woolly Adelgid, Adelgespiceae (Ratz.) (Hemipt., Adelgidae): A Hypothesis,” Applied Entomology, Vol. 99, No. 2, 1985, pp. 145-152.
R. Bruck and W. P. Robarge, “Change in Forest Structure in the Boreal Montane Ecosystem of Mount Mitchell, North Carolina,” European Journal of Forest Pathology, Vol. 18, No. 6, 1988, pp. 357-366. http://dx.doi.org/10.1111/j.1439-0329.1988.tb00223.x
T. A. Bowers, “Forest Structure and Health Trends in the Southern Appalachian Montane Spruce-Fir and Northern Hardwood Ecosystems of the Black Mountains, North Carolina,” North Carolina State University, Raleigh, 2005.
H. S. Adams, S. L. Stephenson, T. J. Blasing and D. N. Duvick, “Growth-Trend Declines of Spruce and Fir in Mid-Appalachian Subalpine Forests,” Environmental and Experimental Botany, Vol.25, No. 4, 1984, pp. 315-325.
J. A. Witter and I. R. Ragenovich, “Regeneration of Fraser Fir at Mt. Mitchell, North Carolina, after Depredations by the Balsam Woolly Adelgid,” Forest Science, Vol. 32, No. 3, 1986, pp. 585-594.
N. S. Nicholas, “Stand Structure, Growth, and Mortality in Southern Appalachian Spruce-Fir,” Virginia Polytechnic Institute and State University, Blacksburg, 1992.
C. Eager, “Review of the Biology and Ecology of the Balsam Wolly Aphid in Southern Appalachian Spruce Fir Forests,” In: P. White, Ed., The Southern Appalachian Spruce Fir Ecosystem: It’s Biology and Threats, US National Park Service, Gatlinburg, 1984, pp. 36-50.
G. F. Smith and N. S. Nicholas, “Size and Age Class Distributions of Fraser Fir Following Balasm Woolly Adelgid Infestation,” Canadian Journal of Forest Research, Vol. 30, No. 6, 2000, pp. 948-957. http://dx.doi.org/10.1139/x00-028
R. T. Busing, “Red Spruce Dynamics in an Old Southern Appalachian Forest,” Journal of the Torrey Botanical Society, Vol. 131, No. 4, 2004, pp. 337-342.
P. Soule, “Changing Climate, Atmospheric Composition, and Radial Tree Growth in a Spruce-Fir Ecosystem on Grandfather Mountain, North Carolina,” Natural Areas Journal, Vol. 31, No. 1, 2011, pp. 65-74. http://dx.doi.org/10.3375/043.031.0108
U. Congress, “42 USC Chapter 85, Subchapter IV-A Acid Deposition Control,” US Federal Register, Washington DC, 1990.
R. H. McManamay, L. M. Resler, J. B. Campbell and R. A. McManamay, “Assessing the Impacts of Balsam Woolly Adelgid (Adelgespicae Ratz.) and Anthropogenic Disturbance on the Stand Structure and Mortality of Fraser Fir [Abiesfraseri (Pursh) Poir.] in the Black Mountains, North Carolina,” Castanea, Vol. 76, No. 1, 2011, pp. 1-19. http://dx.doi.org/10.2179/09-059.1