Effects of Fire Suppression in Northern Hardwoods

While the era of fire suppression in the 20^th century had negative effects on fire-adapted and fire-dependent communities like oak and pine forests, it has generally had a neutral to positive effect on fire-sensitive northern hardwood forests.  Many former oak forests have, in the absence of fire, been replaced by other hardwood species like red maple (Acer rubrum), yellow poplar (Liriodendron tulipifera) and hickories (Carya spp.). However, northern hardwoods had a chance to recover from high-intensity slash fires after large-scale logging in the late-1800s and early 1900s. Presently, about 68% of Southern Appalachian high elevation hardwoods are in a mid-successional stage, 18% have reached sapling or pole size, about 13% are late successional and 1% is early successional (Hunter et al. 1999).

Fire suppression and management towards old-growth forest in northern hardwoods has resulted in a lack of large openings, which in turn seems to have caused the present rarity of Appalachian yellow-bellied sapsuckers in the Great Smoky Mountains National Park.  Although sapsuckers need mature trees for their cavities, they depend on young trees for harvesting sap and insects to feed their young ones. Other bird species also profit from some kind of disturbance causing a more complex vegetation structure: black-throated blue warbler and veery demand a dense understory; ruffed grouse needs more early-successional habitat (Hunter et al. 1999).   Prescribed fire programs, however, have never focused on fire-sensitive northern hardwood communities, since other management techniques like thinning or shelterwood cutting can create a more complex vegetation pattern providing the necessary habitat for those bird species.