Chapter 4 Habitats
hickory forests are on dissected landscapes comprising multiple community types and are not extensive. While most component species are abundant and widespread, some species, particularly mammal and bird species, may only be able to persist in large areas or they may be excluded from areas near the forest edge. The chances for some of these animals to survive may be enhanced by protecting forested connections between larger forested blocks. Fire Suppression. Fire is believed to have been a natural part of all Piedmont and Coastal Plain Oak Forests. While its frequency and importance are not precisely known, regular fires give a competitive advantage to oaks, hickories, and Shortleaf Pine relative to most other tree species. There is now much concern that these species are not regenerating. Other species are much more abundant in forest understories and are increasing in the canopy. Harvests that once resulted in regeneration of oaks now often lead to stands of other species. Fires also lead to more open canopy conditions and greater cover and diversity of herbs. Low intensity fires would be beneficial, but intense wildfires can be destructive. Regular fires also reduce fuel loads and reduce the potential for catastrophic canopy-killing fires. The restriction of Oak Forests in the Coastal Plain to fire-sheltered sites suggests a need for fires to be less frequent than in the Longleaf Pine communities that occupied the uplands. The Xeric Hardpan Forests appear to have changed most with removal of fire, but fire probably had similar, if less dramatic, effects on the other community types. Most or all rare plants in this group are likely to benefit from fire and the habitat conditions it creates. Invasives. The occurrence of invasive and nonnative plants is a problem for Oak-hickory forests in some places and is likely to continue to spread. Princess Tree and Tree-of-heaven can invade disturbed areas and occupy canopy gaps in some places. Autumn Olive has come to dominate the shrub layer in some forests, and species such as Trifoliate Orange represent a potential threat. Several herbaceous exotic plants also invade these forests, particularly those with basic soils. It is unclear if a warmer climate will exacerbate their spread; however, increased canopy disturbance by wind, drought mortality, or severe fire will hasten the spread of invasive species. Climate Change. Most Oak Forests are tolerant of drought. Increased occurrence or longer periods of drought may favor oaks relative to weedy mesophytic species, but increased wind damage favors the understory species. If drought leads to severe wildfires, it would be harmful to Oak Forests, but the ease with which fires may usually be controlled in them makes this unlikely. Increased wind throw would probably favor existing understory maples over the long- lived oaks. Older trees will withstand fire better than younger ones but will be more susceptible to wind. Increased wind throw would reduce the average longevity of trees. The most severe droughts and hot spells of recent record have had only limited effects on Oak Forests. These forest types occupy the driest places on the Piedmont landscape. In general, the effects of drought, fire, and storm winds are small relative to the effects of development and logging.
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2025 NC Wildlife Action Plan
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