Great Smoky Mountains National Park, Classic Cove Hardwood Forest

Forest Summary

  • Found along streams and on north-facing, low protected slopes in the middle elevation zone.

  • Yellow birch is absent or rarely dominant.
  • Subcanopy and understory are usually thin.
  • Herbaceous layer is usually very rich and diverse.

Forest Description

We apply the term “classic” in this article to the middle elevation cove hardwood forest to emphasize the outstanding character of this forest found only in the southern Appalachian Mountains and to distinguish it from the less unique low elevation river cove forest. Classic Cove hardwood forests are found between 2500 feet and 4000 feet elevation in coves along most of the Park’s less acidic streams. Often the coves are narrow, rocky and steep. Middle elevation gaps like Cucumber Gap and flats also support classic cove hardwood forests.

There are pockets of virgin classic cove hardwood forest in many parts of the Park. Most occur in the northeastern section where the largest tracts of virgin forest of any kind in eastern America exist. The Greenbriar and upper Cosby Coves are access points for many of these magnificent forests. Also called the southern Appalachian cove forest, or simply the cove hardwood forest, the classic cove hardwood forest is the botanical wonderland of our Eastern forests. Nowhere else in eastern America exists a forest with such plant riches. Several reasons account for much of this diversity. During the last ice age plants and animals retreating from northern ice sheets found refuge in the southern Appalachian Mountains. Here trees from the north crowded in with trees from the south eventually forming new forest associations, some unique to these mountains.

Another reason for the richness of the classic cove hardwood forest is lack of disturbance. Though many of these higher coves were completely logged, most were not subjected to the intensive grazing and crop raising that occurred along lower elevation coves. As a result the rich herbaceous plant layer is fairly intact.

A third reason for the plant riches found here relates to ideal growing conditions. The combination of cooler summertime temperatures, ample rain, rich moist soil and protection from extremes of heat and cold by adjacent mountain slopes provides a made-to-order growing environment. Given enough time trees here can reach enormous proportions, and fortunately, the inaccessibility of these mountains has in many cases afforded the time.

The canopy of the classic cove hardwood forest is characteristically dominated by a large number of tree species sharing the canopy. The species mix can vary depending on site characteristics and history, but usually consists of some mix of the trees listed in the table above. An abundance of pioneer trees like yellow poplar, cucumbertree and black cherry usually indicates a younger forest than one where these three species are fewer in number, larger in size and accompanied by medium-size shade tolerant trees like basswood, hemlock and buckeye. Indeed, it may not be possible to account for all the different combinations of tree dominants these forests exhibit. Part of the excitement and wonder of entering the classic cove hardwood forest is discovering what mix of trees awaits the tree enthusiast. Few can emerge from such a forest without a sense of enrichment and a feeling of reverent awe.

Another characteristic aspect of the classic cove hardwood forest is its rich herbaceous plant layer. Subcanopy and understory trees are usually sparse allowing enough sunlight and moisture for a lush carpet of colorful wildflowers, grasses, sedges and ferns to flourish. Visualize yourself wandering through such a forest on a warm, sunny April afternoon with shafts of sunshine highlighting these forest beauties. Your dreams await you in GSMNP!

As you ascend toward 4000 feet especially on the North Carolina side of the main divide, cool cove forest trees begin to dominate the classic cove forest mix while lower elevation trees drop out. Yellow poplar, bitternut hickory and cucumbertree disappear. Basswood thins out while yellow birch and buckeye increase. Flowering dogwood, spicebush and sweetshrub drop out of the understory. Striped maple and alternate-leaf dogwood increase.

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About Dan Williams

Forest manager & environmental educator with the Warnell School of Forestry and Natural Resources. I have spent 26 years interpreting forest research for non-scientists interested in learning more about the forests of the Southeastern United States.
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