Mountains and Interior Highlands Fire Regimes

Fire played a major role in shaping vegetation communities in the Appalachian Mountains. Overstories of southern yellow pines (Virginia, shortleaf, pitch, and Table Mountain) typically dominate south- and west-facing slopes (Whittaker 1956), but in the absence of hot fires at rather frequent intervals, hardwoods will succeed pines. Table Mountain pine is well adapted to fire because of its serotinous cones. Although these can open without fire, many remain closed and ensure a supply of seed regardless of the time of year when a fire occurs (Barden 1977). This adaptation allows Table Mountain pine to cast seeds when seeds of other pine species would be destroyed. Serotinous cones have also been observed in pitch pine and rarely in Virginia pine, but this character is not well documented. Shortleaf and pitch pines can sprout from the root collar after topkill by fire. Fires of human origin probably perpetuated pine in the Appalachians since lightning fires did not occur frequently enough or were not intense enough to maintain pines on these xeric sites (Whittaker 1956). Fire protection in recent decades has allowed hardwoods to dominate on sites where pines once thrived.

• Oak-hickory forests
• Mixed mesophytic hardwoods
• Table Mountain pine
• Pitch and Virginia pines
• Southern forest types with long fire-return intervals