Background

Forests in the southeastern United States (U.S.) are an integral component of the local, regional, and global economies.  Southeastern forests are a complex and diverse mosaic of hardwood and conifer tree species ranging from high-elevation white pine-spruce-hemlock forests to lower elevation piedmont and coastal plain oak-hickory and southern pine forests.  Various endemic species of southern pines including loblolly (Pinus taeda), longleaf (P. palustris), shortleaf (P. echinata), and slash (P. elliottii) pines cover ~45% of the total forested area, of which about 60% is planted and commercially managed. Forest cover-types such as oak (Quercus spp.)-pine, oak-hickory (Carya spp.), and bottomland forests dominate the hardwood forest (USDA Forest Service 2004). Comprising nearly 29% of the total forestland in the U.S., southeastern forests cover about 86 million hectares ranging from Kentucky in the north to Florida in the south, and Texas in the west to Virginia in the east. While these forests comprise only 2% of the earth’s terrestrial landscape, they provide 58% of timber in the U.S. and 18% of world’s total pulpwood (World Resources Institute 2010). Further, these forests are gaining importance in terms of biomass fuel production from logging slash and use of hardwood plantations. Considering their economic importance regional to global scale, southeastern forests are aptly termed as the “wood baskets” of the world. 

In addition to providing economic values, southeastern forests are ecologically important as they “are considered among the most biologically diverse temperate forests in the world” (Trani 2002). It is estimated that these forests contain the highest diversity of plant species in North America, along with thousands of indigenous mammal and bird species, and they are a hotspot of amphibian and reptile diversity (World Resources Institute 2010). For example, diverse habitats in the southeastern forests host over 3,000 plant, 595 bird, 246 mammal, and 367 herpetofaunal species (Tranie 2002). Like forests elsewhere, those in the Southeast provide critical ecosystem services, such as maintaining drinking water quality, improving air quality, preventing soil erosion, pollination, sequestering carbon, and non-timber products such as medicinal and landscape plants and pine needles for mulching (USDA Forest Service 1988). Further, these forests provide tourism (e.g., hiking and camping), recreation (e.g., hunting and fishing), and aesthetic values to the public. A recent study by Moore et al. (2013) assessed the value of essential ecosystem services such as carbon storage and water, air, recreational and aesthetic qualities of 8.9 million hectares of private forests in Georgia.  They summarized that the value of ecosystem services is ~$38 billion per year (Moore et al. 2013) which is greater than the estimated economic value of $30 billion per year from timber harvest for multiple uses (World Resource Institute 2010).  Long-term resilience and sustainability of southeastern forests is therefore, critical to maintaining both the economic and ecological services provided by these forested landscapes.

Southern pine health is affected by many abiotic and biotic factors. Rarely do these factors act singly; rather, several often act together to affect pine health. Abiotic factors affecting pine health include temperature, rainfall/drought, soil type, slope, and aspect. Biotic factors include insects and fungi such as southern pine beetle, ips beetles, and heterobasidion. Human impacts, such as mechanical damage from harvesting equipment, the use of herbicide and prescribed fires, can also affect pine health.

References

USDA Forest Service. 1988. The South's fourth forest: alternatives for the future. USDA Forest Service, Forest Resource Report Number 24.

Moore, R., Williams, T., Rodriguez, E., and Hepinstall-Cymmerman, J. 2013. Using non-market valuation to target conservation payments: An example involving Georgia's private forests. Journal of Forestry 111:261-270.