Chapter 4 Habitats
4.4.4 Northern Hardwood Forests 4.4.4.1 Ecosystem Description
Classification of the Natural Communities of North Carolina, Fourth Approximation (Schafale 2024) includes this natural community as Northern Hardwood Forests Theme. Northern hardwood forests are found on high mountain slopes with a cool climate and high levels of rainfall in western North Carolina and are concentrated in many of the same high-elevation areas as Spruce-Fir forests. The name refers to the resemblance of these forests to those in the northeastern United States, which have similar canopies, but the presence of southern Appalachian endemic species makes the community types in North Carolina different from those in the north. High-elevation climate, slope, aspect, and past disturbance are critical ecological determinants of the distribution of northern hardwood forests today. In general, they are widespread throughout the region owing to their lower elevation range. Northern hardwood forests are dominated by combinations of moist-site hardwoods such as Yellow Birch, American Beech, Yellow Buckeye, and Sugar Maple. The herb layer is often lush and may range from low to fairly high diversity. These forests are subject to periodically widespread disturbances, such as ice storms or severe winds, which provide canopy openings, but probably seldom or never remove the whole canopy at once.
There are four recognized subtypes in this community theme, determined primarily by topography and soil chemistry (Schafale 2024) .
• High Elevation Birch Boulderfield Forest • Northern Hardwood Forest (Typic Subtype, Rich Subtype, Beech Gap Subtype)
The typic subtype varies in composition and diversity. Some have a lawn-like ground cover of just a few species of sedges and grasses, while others have a lush and diverse herb layer. The rich subtype is found at higher elevations, occurring on exposed or somewhat sheltered sites. It encompasses the rare examples on mafic or calcareous rock substrates, which contain flora of rich soils, including many species shared with Rich Cove Forest. The beech gap subtype occurs in high-elevation gaps and peaks, where beech trees stunted by the wind predominate. In the most extreme cases, the tree canopy may be reduced to shrub size. The trees may be quite old, although small, as growth and reproduction are relatively slow. In the boulderfield forest, Ice Age freeze–thaw processes have left the ground completely covered with large boulders with very little soil. These areas are found above 4,000 feet elevations and are dominated by Yellow Birch with a distinctive undergrowth of gooseberries and moss on the rocks.
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2025 NC Wildlife Action Plan
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