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Heath Bluff

Sites

Steep slopes and bluffs, generally north facing, on acidic substrates. Generally in areas of hard rock, but may occur in areas of soft material exposed by undercutting by a stream.

Soils

Thin and rocky soils. Series mapped include Goldston, Tarrus, Wateree, and Wedowee.

Hydrology

A combination of dry conditions caused by shallow, well-drained soil and cool, moist microclimate caused by north slope, seems to be responsible for the formation of these communities. Sites may be somewhat heterogeneous, with dry microsites intermixed with wet seepage areas.

Vegetation

Canopy

The tree canopy is open to very sparse, with trees such as Quercus montana (Rock Chestnut Oak), Pinus taeda (Loblolly Pine), P. virginiana (Virginia Pine), Acer rubrum (Eastern Red Maple), Oxydendrum arboreum (Sourwood) and Amelanchier arborea (Downy Serviceberry) characteristic. A variety of trees from surrounding forests may occur.

Understory

A dense shrub layer of Kalmia latifolia (Mountain Laurel) or Rhododendron catawbiense (Catawba Rhododendron) dominates the sites. Other shrubs may include Gaylussacia frondosa (Dangleberry), Vaccinium spp. (Blueberry) and Hamamelis virginiana (Northern Witch-hazel).

Herb Layer

Herbs are generally sparse under the shrubs, with acid-loving species such as Mitchella repens (Partridge-berry), Galax urceolata (Galax), Hexastylis minor (Little Heartleaf), Gaultheria procumbens (Wintergreen), Chimaphila maculata (Pipsissewa) and Epigaea repens (Trailing Arbutus) typical. Outcrop herbs may occur on interspersed rocks.

Dynamics

The long-term dynamics of these communities are not known. The heaths and other species are generally confined to these communities as disjunct occurrences. They are probably relict occurrences from past cooler climate. This suggests long-term stability of these communities, with further succession to forest cover halted, perhaps by competition from the dense shrub layer. The cool steep slopes, generally bordering floodplains, seem unlikely to be subject to fire.

Associations

Generally borders a floodplain forest or a stream channel. May grade to such communities through a talus slope at the base. Above, may grade to various upland communities, such as Mesic Mixed Hardwoods Forest, Dry Oak-Hickory Forest, or Dry-Mesic Oak-Hickory Forest, on less steep and rocky slopes. May be associated with Acidic Cliff.

Comments

The cause of their distinctive vegetation is apparently related to both shallow soil and cool microclimate. These communities are somewhat rare because of the relatively rapid weathering in this region, but they are better protected against destruction than most communities. They can, however, be severely damaged by climbing and scrambling in heavily used areas.