Name:
Juniperus virginiana / Schizachyrium scoparium - (Andropogon gerardii, Sorghastrum nutans) - Silphium terebinthinaceum Wooded Grassland
Reference:
NatureServe Biotics 2019
Description:
These red-cedar / little bluestem limestone barrens have been observed on Silurian exposures of Decatur and Perry counties, Tennessee (Western Highland Rim in the Western Valley of the Tennessee River) and Mississippian exposures of the Moulton Valley of Colbert and Franklin counties of northern Alabama. The Tennessee examples occur on slopes of Silurian geology, of the Brownsport, Dixon, and Beech River formations. Two phases of this vegetation have been observed. Areas presumably of deeper soil are dominated by <i>Andropogon gerardii, Sorghastrum nutans</i>, and <i>Schizachyrium scoparium</i>. Other forbs dominant to present in this phase include <i>Liatris aspera, Silphium terebinthinaceum, Silphium trifoliatum var. latifolium</i>, and <i>Brickellia eupatorioides</i>. This vegetation covers extensive areas at one site, where very old, gnarled <i>Juniperus virginiana var. virginiana</i> are present at a cover of 15-20%, Mortality and/or morbidity caused by drought maintains the tree cover at below 20% even in fire-suppressed examples. This phase grades into areas of shallower soil with a sparser grass cover (about 50%), composed primarily of <i>Schizachyrium scoparium</i>. Also present in this more common <i>Schizachyrium</i>-dominated phase are <i>Liatris cylindracea, Physostegia virginiana ssp. praemorsa, Ruellia humilis</i>, annual <i>Sporobolus</i> sp., <i>Symphyotrichum concolor, Symphyotrichum shortii</i>, and <i>Heliotropium tenellum</i>. Up to 50% of the ground surface in the drier phase may be covered by red or gray fossiliferous gravel in the Tennessee examples, or by shaly, "marly" limestone fragments in Moulton Valley, Alabama, ones. State-rare plants in Tennessee examples (disjunct from farther west) include <i>Liatris cylindracea, Symphyotrichum pratense</i> and <i>Salvia azurea var. grandiflora</i>. Alabama examples (but not Tennessee ones as far as known) may contain the globally rare <i>Eriogonum longifolium var. harperi</i>, and may locally grade down into small seepages with <i>Schoenolirion croceum</i> [see ~<i>Eleocharis (bifida, compressa) - Schoenolirion croceum - Carex crawei - Allium cernuum</i> Seep Grassland (CEGL004169)$$]. The Tennessee sites are among the most extensive areas of Silurian surface geology in the unglaciated continental United States.
Accession Code:
urn:lsid:vegbank.org:commConcept:33516-{5F33C4A3-6F29-4663-B77D-6E141EF8EE44}
Plot-observations of this Community Concept:
14
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