Common (Translated Scientific) Name: Post Oak - Blackjack Oak / Little Bluestem - Prairie Rosinweed Wooded Grassland

Colloquial Name: Post Oak Chert Barrens

Hierarchy Level:  Association

Type Concept: This barrens or post oak openings community is found in the midwestern United States in southern Indiana and Ohio. Stands occur on rolling hill-and-swale topography over limestone or shale bedrock. The soils are stony and excessively well-drained. This is a prominent community on the Mitchell Karst Plain in south-central Indiana. There, it occurs on rolling hill-and-swale topography on a large sinkhole plain over limestone bedrock. Soils are formed from chert residue left from the erosion of limestone bedrock. These soils are stony, acidic, and excessively well-drained. In Ohio, this community occurs in the unglaciated Bluegrass Region, north of West Union in Adams County, where it is found only over Crab Orchard Shale, on slight slopes or mounded outcrops. On slopes, deep erosional gullies are usually present. Crab Orchard Shale is calcareous and weathers to a light brown to yellowish heavy silt loam containing scattered pieces of dolomite. Fire, drought and grazing are factors in maintaining the open woody character of this type. Vegetation may be sparse, consisting of xeric species and stunted individuals of species that reach considerable size elsewhere. Graminoids, such as Schizachyrium scoparium and Sorghastrum nutans, form most of the vegetation cover in this community, but tree canopy species may include Juniperus virginiana var. virginiana, Quercus alba, Quercus imbricaria, Quercus marilandica, Quercus stellata, and Quercus velutina. Herbaceous species which may be present include Aconitum uncinatum, Allium cernuum, Andropogon gerardii, Aristida longespica, Asclepias amplexicaulis, Carex meadii, Danthonia spicata, Eryngium yuccifolium, Euphorbia corollata, Helianthus mollis, Helianthus hirsutus, Houstonia sp., Liatris cylindracea, Liatris squarrosa, Lobelia spicata, Panicum flexile, Pycnanthemum tenuifolium, Rudbeckia hirta, Salix humilis, Silphium trifoliatum, and Sporobolus vaginiflorus.

Diagnostic Characteristics: No Data Available

Rationale for Nominal Species or Physiognomic Features: No Data Available

Classification Comments: In southeastern Ohio, Cedar Barrens also occur on Crab Orchard Shale. The two types are not easily separable because they contain many of the same species. There is some difference in their topographical distribution, however. Cedar Barrens occur on steeper slopes that may have originally been covered by Acer saccharum. Cedar Barrens also lack certain species characteristic of this community, such as Silphium terebinthinaceum. The post oak chert barrens stands in Ohio also intergrade with a shale glade type, ~Quercus marilandica - (Juniperus virginiana) / Schizachyrium scoparium - Danthonia spicata Wooded Grassland (CEGL002428)$$; the shale glades tend to be of low diversity, and most are disturbed by relatively recent farming efforts and by erosion, and are overgrown. It may be that these shale glades in Ohio should just be combined with this type (D. Minney pers. comm. 2000). Schizachyrium scoparium prairies (limestone glades) are also similar to this community. The prairies or glades have a nearly complete vegetative cover and occur over dolomite rather than shale. They are tracked as ~Quercus muehlenbergii - Juniperus virginiana / Schizachyrium scoparium - Manfreda virginica Wooded Grassland (CEGL005131)$$, and they also contain a distinctive zone tracked as a separate type, the ~Juniperus virginiana / Schizachyrium scoparium - Silphium terebinthinaceum var. luciae-brauniae - Carex juniperorum - Castilleja coccinea Wooded Grassland (CEGL004464)$$.

Similar NVC Types: No Data Available

note: No Data Available