1. School of Forestry and Wildlife Sciences, 3301 SFWS Building, Auburn University, Auburn, AL 36849-5418, USA.
2. USDA Forest Service, Southern Research Station, 2500 Shreveport Highway, Pineville, LA 71360, USA.
3. USDA Forest Service, Southern Research Station, 705 Spear Street, South Burlington, VT 05403, USA.
4. USDA Forest Service, Southern Research Station, P.O. Box 12254, Research Triangle Park, NC 27709, USA.