Physiognomy and Structure: Examples are dominated by a mixture of forbs and grasses, including many diminutive annuals. The community types in this alliance are generally distinguished by their herbaceous cover being associated with exposed sandstone outcrops, flats, and ledges, intermixed with dense, herbaceous patches, scattered stunted trees and shrubs, and fruticose lichens. The herbaceous flora is diverse and varies considerably seasonally. Much of the dry sandy soil and rock is unvegetated. Occurrences may appear almost devoid of vegetation during the dry summers, while the spring and autumn are periods of peak flowering. Most examples occur within a matrix of open Pinus palustris woodlands.

Floristics: The alliance is dominated by prairie-like vegetation. Bigelowia nuttallii is a late-summer and fall aspect dominant. Examples found on coastal plain sandstone (Altamaha Grit) outcrops are dominated by prairie-like vegetation with Bigelowia nuttallii, as well as Aristida longespica, Croton michauxii (= Crotonopsis linearis), and Schizachyrium scoparium as primary components. The herbaceous flora is rich in endemic and disjunct species; additional ones include Allium cuthbertii, Aristida beyrichiana, Coreopsis major, Liatris squarrosa, Manfreda virginica, Penstemon dissectus, Schizachyrium tenerum, Phemeranthus teretifolius (= Talinum teretifolium), and Tephrosia virginiana. Scattered trees and shrubs can be rooted in deeper soils or crevices, including Pinus palustris, Quercus marilandica, and Vaccinium arboreum. Sandstone glades of panhandle Florida are dominated by Bigelowia nuttallii. Other characteristic species include Eurybia hemispherica (= Aster paludosus ssp. hemisphericus) and Schizachyrium scoparium var. scoparium. Sandstone outcrops may contain scattered Ilex vomitoria, Morella cerifera (= Myrica cerifera), Pinus echinata, Pinus palustris, Pinus taeda, Quercus marilandica, and Quercus stellata.

Dynamics:  These openings occur within a matrix of open Pinus palustris woodlands, and their structure and composition will be affected by fires that burn through these adjacent woodlands.