Physiognomy and Structure: No Data Available

Floristics: Stands are dominated by a mixture of Quercus muehlenbergii, other oaks (particularly Quercus alba and Quercus rubra), and several hickories (Carya cordiformis, Carya glabra, and Carya ovalis). Fraxinus americana, Liriodendron tulipifera, Acer saccharum, Quercus velutina, Ulmus rubra, Tilia americana, and Juglans nigra may also be present in the canopy. Disturbed stands may have a higher proportion of Fraxinus americana, Celtis occidentalis, and other early-successional species in the overstory. The relatively open subcanopy may contain Acer saccharum, Aesculus flava, and Juniperus virginiana var. virginiana, as well as smaller individuals of Fraxinus americana and Carya spp. Viburnum prunifolium, Cercis canadensis var. canadensis, Cornus florida, Ulmus rubra, Ostrya virginiana, Viburnum prunifolium, and Asimina triloba are present as tall shrubs or small trees. Low shrubs include Rhus aromatica var. aromatica, Dirca palustris, Staphylea trifolia, and Toxicodendron radicans. Herbs present include Ageratina altissima, Amphicarpaea bracteata, Asclepias quadrifolia, Bromus pubescens, Brachyelytrum erectum, Circaea lutetiana ssp. canadensis, Collinsonia canadensis, Dichanthelium boscii, Dioscorea quaternata, Desmodium glutinosum, Elymus hystrix var. hystrix, Euphorbia mercurialina, Eurybia divaricata, Galium circaezans, Geranium maculatum, Hexastylis arifolia var. ruthii, Houstonia longifolia, Hydrophyllum virginianum, Maianthemum racemosum, Oxalis grandis, Packera obovata, Polystichum acrostichoides, Sanicula odorata, Sanguinaria canadensis, Sedum ternatum, Thaspium barbinode, Viola x palmata, and Viola pubescens. Some small patches of Arundinaria gigantea are also present in stands at the southern end of the range. Additional species characteristic of plot samples at the northern end of the range are Festuca subverticillata, Viola sororia, Cardamine concatenata, Geum canadense, Arisaema triphyllum, Actaea racemosa, Dicentra cucullaria, Claytonia virginica, Polygonum virginianum, Corydalis flavula, Eurybia divaricata, Podophyllum peltatum, and Viola striata. Several species that are more typical of basic mesic forests (e.g., Asarum canadense, Jeffersonia diphylla, Hybanthus concolor, and Dicentra canadensis) occasionally exhibit strong patch-dominance in this community, although none of these species occurs with high constancy. In Lee County, VA, Hydrastis canadensis frequently forms large clones in this forest. Additional, relatively inconstant herbs that occasionally cover >1% of an individual stand include Sanicula odorata, Bromus pubescens, Maianthemum racemosum ssp. racemosum, Sanguinaria canadensis, Galium concinnum, Hepatica nobilis var. obtusa (= Hepatica americana), Polymnia canadensis, Stellaria pubera, and Carex jamesii. Many additional herbs occur at low cover and constancy.

Dynamics:  Contemporary examples of this vegetation type are probably quite different from mature stands that existed prior to the extensive post-settlement landscape alterations that occurred in the fertile limestone portions of the Ridge and Valley province. Codominance by trees such as Celtis occidentalis and Fraxinus americana is generally regarded as an indicator of heavy past disturbances and secondary succession. In a large and relatively mature stand (Frederick County, Virginia) that had experienced past cutting but no agricultural impacts, the overstory codominants were (in roughly descending order of importance) Quercus muehlenbergii, Quercus alba, Quercus rubra, Carya cordiformis, Carya ovalis, and Fraxinus americana; Quercus velutina was also common in certain parts of the site that seemed a little drier and stonier. The ubiquity of invasive weeds (e.g., Alliaria petiolata and Lonicera japonica) in most sampled and observed stands adds to the evidence that most examples are degraded. Moreover, at least in Virginia, where almost all of the prime habitats for this vegetation are located on private lands, inventory and documentation of the type have been very poor. All of these factors make characterization difficult. However, existing data and observations suggest that the type is widely distributed in the Ridge and Valley from western Maryland to Tennessee. Although opportunistic, early- and mid-successional species such as Celtis occidentalis and Fraxinus americana may persistently codominate many stands; oaks and hickories are likely to be the climax species in the absence of human disturbances.