Theodor D. Leininger, USDA Forest Service, Bugwood.org

Minnesota Department of Natural Resources - FIA , Minnesota Department of Natural Resources, Bugwood.org

Edward L. Barnard, Florida Department of Agriculture and Consumer Services, Bugwood.org

Robert L. Anderson, USDA Forest Service, Bugwood.org

USDA Forest Service - Northern and Intermountain Region , USDA Forest Service, Bugwood.org