Montane Dry Calcareous Forest and Woodlands
These deciduous or occasionally mixed forests and woodlands occur on subxeric to xeric, fertile habitats over carbonate formations of limestone and dolomite, or very rarely highly calcareous siltstone or shale. Habitats are steep, usually rocky, south- to west-facing slopes at elevations from < 300 to 900 m (< 1,000 to 2,900 ft). Soils vary from circumneutral to moderately alkaline and have high calcium levels. Confined in Virginia to the mountains, these communities are most frequent and extensive in the Ridge and Valley, but occur locally in both the Blue Ridge and Cumberland Mountains. Tree canopies vary from nearly closed to sparse and woodland-like. Overstory mixtures of chinquapin oak (Quercus muehlenbergii), sugar maple (Acer saccharum), black maple (Acer nigrum), northern red oak (Quercus rubra), white oak (Quercus alba), Shumard oak (Quercus shumardii), white ash (Fraxinus americana) and blue ash (Fraxinus quadrangulata, extreme southwest Virginia only) are typical. These forests and woodlands share many understory and herbaceous plants with the Piedmont / Mountain Basic Woodlands group and are similarly species-rich. A few of the taxa that are confined to or most important in the limestone and dolomite communities include Carolina buckthorn (Frangula caroliniana), round-leaved ragwort (Packera obovata, = Senecio obovatus), robin's-plantain (Erigeron pulchellus var. pulchellus), American beakgrain (Diarrhena americana), slender muhly (Muhlenbergia tenuiflora), black-seed ricegrass (Patis racemosa), limestone purple sedge (Carex purpurifera , in extreme southwestern Virginia only), hairy sunflower (Helianthus hirsutus), small-headed sunflower (Helianthus microcephalus), northern leatherflower (Clematis viorna), eastern shooting star (Primula meadia), hoary puccoon (Lithospermum canescens), and white death-camas (Anticlea glauca).
Considerable compositional variation is evident in these communities across western Virginia. A rare and distinctive community type in this group, confined to the largely dolomitic Elbrook formation in the southwestern Ridge and Valley, features an abundance of the magnesiophiles Appalachian ragwort (Packera paupercula var. appalachiana = Senecio plattensis), glade wild quinine (Parthenium auriculatum), and tall larkspur (Delphinium exaltatum), as well as populations of the federally listed smooth coneflower (Echinacea laevigata) and the globally rare, Virginia endemic Addison's leatherflower (Clematis addisonii)References: Fleming (1999), Fleming and Coulling (2001), Rawinski et al . (1996).
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A dry, rocky, open forest of oaks (Quercus spp.), white ash (Fraxinus americana), and eastern red cedar (Juniperus virginiana var. virginiana) at the top of a limestone bluff along the Shenandoah River in Clarke County. Gary P. Fleming / © DCR Natural Heritage. A dry, forb-rich calcareous woodland of chinquapin oak (Quercus muehlenbergii), Shumard oak (Quercus shumardii), and eastern red cedar (Juniperus virginiana var. virginiana) in the northern Shenandoah Valley (Frederick County). Downy wood mint (Blephilia ciliata) and nettle-leaf sage (Salvia urticifolia) are blooming in foreground.Gary P. Fleming / © DCR Natural Heritage.
Glade wild quinine (Parthenium auriculatum) and hoary puccoon (Lithospermum canescens , flowering) in the vernal herb layer of a Ridge and Valley dolomite woodland. Montgomery County.Photo: Irvine Wilson / © DCR Natural Heritage.
Dry calcareous forest on a limestone slope above Cripple Creek, Wythe County (George Washington and Jefferson National Forests).Gary P. Fleming / © DCR Natural Heritage.
REPRESENTATIVE COMMUNITY TYPES:
This group is currently represented by 71 quantitative plot samples spanning the full length of western Virginia (map). Examples occurring on Ridge and Valley limestone and dolomitic substrates have been widely sampled and robustly classified (USNVC CEGL006017, CEGL006231 and CEGL006030). It is not clear, however, whether the full range of compositional variation in this group over the whole region has been sufficiently documented. Types classified from data collected in the Cumberland Mountains (CEGL008458) and extreme southwestern Virginia (CEGL007699) appear conceptually sound, but are represented by far fewer, geographically restricted plots. Future data collection and analysis will likely result in refinements to the nomenclature and description of these types, and possibly in the identification of one or more additional types.
Click on any highlighted CEGL code below to view the global USNVC description provided by NatureServe Explorer.