Print Report
CEGL007073 (Juniperus virginiana) / Sporobolus vaginiflorus - Panicum flexile - Allium cernuum - Minuartia patula Grassland
Type Concept Sentence: No Data Available
Common (Translated Scientific) Name: (Eastern Red-cedar) / Poverty Dropseed - Wiry Panicgrass - Nodding Onion - Pitcher''s Stitchwort Grassland
Colloquial Name: Virginia Ridge & Valley Limestone Annual Flatrock Barrens
Hierarchy Level: Association
Type Concept: This vegetation is essentially herbaceous but can have scattered shrubs of Juniperus virginiana within open patches and forming denser thickets around the edges. The vegetation is characterized by a mixture of annual grasses and low annual and perennial forbs. The most constant and characteristic species are Allium cernuum, Cuphea viscosissima, Dichanthelium acuminatum, Euphorbia dentata, Trichostema brachiatum, Minuartia patula, Packera anonyma, Panicum flexile, Sedum pulchellum, and Sporobolus vaginiflorus var. vaginiflorus. This community type is developed on gently sloping to flat exposed outcrops of Lincolnshire Limestone, which reaches a maximal thickness of 85 m (280 feet) near Lexington; based on moderately high magnesium levels in soils over the outcrops, the limestone may be dolomitic. These habitats represent discrete openings in subxeric, calcareous forests and woodlands of Juniperus virginiana. Some of the bedrock openings are approximately one half (0.5) acre in size, but most are considerably smaller. Surface substrate consists of about 50% exposed bedrock, cobbles, and gravel, and 50% thin organic matter or exposed mineral soil. The latter is poorly developed, consisting of thin localized mats of yellow-brown or reddish-brown silty clay loam from <4 cm to >6 cm deep over bedrock. Samples collected from plots had consistently high pH (mean = 7.7), calcium (mean = 3650 ppm), magnesium (mean = 175 ppm), and 100% base saturation. Mean slope inclination is about 5°. Abundant ephemeral seepage occurs over parts of the outcrops during wet periods, but the habitat is very drought-prone and xeric overall.
Diagnostic Characteristics: No Data Available
Rationale for Nominal Species or Physiognomic Features: No Data Available
Classification Comments: This is a small-patch type. These habitats represent discrete openings in subxeric, calcareous forests and woodlands of Juniperus virginiana. Some of the bedrock openings are approximately one half (0.5) acre in size, but most are considerably smaller. This vegetation is very distinct from other limestone and dolomite barrens in Virginia, both environmentally and floristically.
Similar NVC Types: No Data Available
note: No Data Available
Physiognomy and Structure: No Data Available
Floristics: This vegetation is essentially herbaceous but can have scattered shrubs of Juniperus virginiana within open patches and forming denser thickets around the edges. The vegetation is characterized by a mixture of annual grasses and low annual and perennial forbs. The most constant and characteristic species are Allium cernuum, Cuphea viscosissima, Dichanthelium acuminatum, Euphorbia dentata, Trichostema brachiatum, Minuartia patula, Packera anonyma, Panicum flexile, Sedum pulchellum, and Sporobolus vaginiflorus var. vaginiflorus. Additional species that can be important in some patches of the type include Croton monanthogynus, Linum sulcatum, Opuntia humifusa, Panicum philadelphicum, Scutellaria parvula var. missouriensis (= Scutellaria leonardii), Scutellaria parvula (var. parvula), Sisyrinchium mucronatum, and Verbena simplex. Perennial graminoids such as Bouteloua curtipendula, Danthonia spicata, Schizachyrium scoparium, and Tridens flavus are infrequent and occur at low cover. In addition to the ubiquitous Juniperus virginiana, other marginal woody components are Cercis canadensis var. canadensis, sapling Fraxinus americana, and Rhus aromatica var. aromatica. The cyanobacterium Nostoc commune is abundant on the flatrocks, becoming particularly conspicuous during periods when moisture is readily available. Among bryophytes, Orthotrichum strangulatum (= Orthotrichum lescurii) is abundant on the rocks. A number of unusual or disjunct (mostly calciphilic) lichens occur, including Placidium squamulosum (= Placynthium squamulosum), Dermatocarpon dolomiticum, Placidium petersii, Psora decipiens, and Thyrea confusa.
Dynamics: No Data Available
Environmental Description: This community type is developed on gently sloping to flat exposed outcrops of Lincolnshire Limestone, which reaches a maximal thickness of 85 m (280 feet) near Lexington; based on moderately high magnesium levels in soils over the outcrops, the limestone may be dolomitic. Surface substrate consists of about 50% exposed bedrock, cobbles, and gravel, and 50% thin organic matter or exposed mineral soil. The latter is poorly developed, consisting of thin localized mats of yellow-brown or reddish-brown silty clay loam from <4 cm to >6 cm deep over bedrock. Samples collected from plots had consistently high pH (mean = 7.7), calcium (mean = 3650 ppm), magnesium (mean = 175 ppm), and 100% base saturation. Mean slope inclination is about 5°. Abundant ephemeral seepage occurs over parts of the outcrops during wet periods, but the habitat is very drought-prone and xeric overall.
Geographic Range: The combination of bedrock type, geomorphological setting, and floristic composition would limit this type to valleys of the Ridge and Valley province in Virginia. It is only known from Rockbridge County (Lexington Limestone Barrens).
Nations: US
States/Provinces: VA
Plot Analysis Summary:
http://vegbank.org/natureserve/ELEMENT_GLOBAL.2.946476
Confidence Level: Low - Poorly Documented
Confidence Level Comments: No Data Available
Grank: G1?
Greasons: No Data Available
| Type | Name | Database Code | Classification Code |
|---|---|---|---|
| Class | 2 Shrub & Herb Vegetation Class | C02 | 2 |
| Subclass | 2.B Temperate & Boreal Grassland & Shrubland Subclass | S18 | 2.B |
| Formation | 2.B.2 Temperate Grassland & Shrubland Formation | F012 | 2.B.2 |
| Division | 2.B.2.Nc Eastern North American Grassland & Shrubland Division | D024 | 2.B.2.Nc |
| Macrogroup | 2.B.2.Nc.3 Little Bluestem - Dropseed species Central Interior Calcareous Scrub & Grassland Macrogroup | M508 | 2.B.2.Nc.3 |
| Group | 2.B.2.Nc.3.b Little Bluestem - Sideoats Grama - Diamond-flowers Central Glade & Barrens Group | G179 | 2.B.2.Nc.3.b |
| Alliance | A1815 Barrens Dropseed - Poverty Dropseed Alkaline Bedrock Annual Grassland Alliance | A1815 | 2.B.2.Nc.3.b |
| Association | CEGL007073 (Eastern Red-cedar) / Poverty Dropseed - Wiry Panicgrass - Nodding Onion - Pitcher''s Stitchwort Grassland | CEGL007073 | 2.B.2.Nc.3.b |
Concept Lineage: No Data Available
Predecessors: No Data Available
Obsolete Names: No Data Available
Obsolete Parents: No Data Available
Synonomy: No Data Available
- Fleming, G. P., K. D. Patterson, and K. Taverna. 2017. The natural communities of Virginia: A classification of ecological community groups and community types. Third approximation. Version 3.0. Virginia Department of Conservation and Recreation, Division of Natural Heritage, Richmond, VA. [http://www.dcr.virginia.gov/natural-heritage/natural-communities/]
- Southeastern Ecology Working Group of NatureServe. No date. International Ecological Classification Standard: International Vegetation Classification. Terrestrial Vegetation. NatureServe, Durham, NC.