Print Report
G671 Croton michauxii var. ellipticus - Minuartia glabra - Packera tomentosa Piedmont Flatrock Group
Type Concept Sentence: This vegetation occupies granitic domes and flatrocks in the southern Piedmont of the United States, and is dominated by Croton michauxii var. ellipticus, Minuartia glabra, Packera tomentosa, Schizachyrium scoparium, and Phemeranthus spp., with Diamorpha smallii having high cover in some examples.
Common (Translated Scientific) Name: Willdenow''s Croton - Appalachian Stitchwort - Woolly Ragwort Piedmont Flatrock Group
Colloquial Name: Piedmont Dome & Flatrock Vegetation
Hierarchy Level: Group
Type Concept: This vegetation occupies granitic domes and flatrocks in the southern Piedmont of the United States. Examples are primarily dominated by Croton michauxii var. ellipticus, Minuartia glabra, Packera tomentosa, Schizachyrium scoparium, and Phemeranthus spp. Some examples may also have Minuartia uniflora (from southern North Carolina southwards) and other annuals, including Diamorpha smallii, which may have high cover in patches. This group also includes seepage areas with greater seasonal moisture availability which contain or are dominated by Portulaca smallii and Phemeranthus teretifolius, with Lindernia monticola present in some occurrences. This vegetation is restricted to granitic domes and flatrocks in the southern Piedmont of the southern United States from Alabama to Virginia. Examples may include shallow depressions and/or seepage areas, as well as the surrounding dry-mesic and dry woodlands. Moisture levels are variable with the seasons, and exhibit some variation among stands.
Diagnostic Characteristics: This distinctive vegetation is restricted to granitic domes and flatrocks in the southern Piedmont of the southern United States from Alabama to Virginia. Examples may include shallow depressions and/or seepage areas, as well as the surrounding dry-mesic and dry woodlands.
Rationale for Nominal Species or Physiognomic Features: No Data Available
Classification Comments: Coffey (1964) cites Diamorpha smallii (as Diamorpha cymosa) as being abundant "in the shallow depressions which dry quickly" and also states that Minuartia glabra (as Arenaria groenlandica var. glabra) and Minuartia uniflora (as Arenaria brevifolia) are also found in these depressions. She does not name or identify either particular zones or specific associations in her work on flat granitic outcrops. Wharton (1978) does not discuss this granite vegetation zone other than citing the work of Baker (1956) and Burbanck and Platt (1964). The rock pools which have deeper and more persistent water are placed in ~Isoetes spp. - Amphianthus pusillus Granitic Outcrop Pool Alliance (A1817)$$. It has been moved from this group (G671) to the wetlands part of the classification.
Similar NVC Types: No Data Available
note: No Data Available
Physiognomy and Structure: These are herbaceous patches in a granitic dome or rock outcrop matrix, with characteristic annual and perennial taxa that exhibit adaptations to the open, seasonally hot and dry environment (reduced leaves, annual or succulent habit, etc.).
Floristics: This vegetation is dominated by Croton michauxii var. ellipticus (= Croton willdenowii), Minuartia glabra, Packera tomentosa, Schizachyrium scoparium, and Phemeranthus (= Talinum) spp. Some examples may also have Juncus georgianus, Minuartia uniflora (from southern North Carolina southwards), and other annuals, including Diamorpha smallii, which may have high cover in patches. This group also includes seepage areas with greater seasonal moisture availability which contain or are dominated by Portulaca smallii and Phemeranthus teretifolius (= Talinum teretifolium), with Lindernia monticola present in some occurrences. Additional species that may be present include Hypericum gentianoides, Isoetes piedmontana, and Selaginella rupestris, as well as the mosses and lichens Cladonia caroliniana, Grimmia laevigata, Philonotis fontana, Polytrichum ohioense, and others (Schafale and Weakley 1990).
Dynamics: No Data Available
Environmental Description: Examples occur in shallow depressions and/or seepage areas associated with granitic outcrops of the southeastern Piedmont, as well as in the surrounding dry-mesic and dry woodlands. Moisture levels are variable with the seasons, and exhibit some variation among stands. These habitats are made wet by the accumulation of water in shallow depressions by rain or by seepage; the hydrological placement is ambiguous. The habitat is actually dry for most of the growing season, but when many of the floristic elements are visible and evident, the substrate is wet. The rock pools which have deeper and more persistent water with Amphianthus pusillus, Isoetes melanospora, Isoetes tegetiformans, and Cyperus granitophilus are not include here.
Geographic Range: This vegetation is primarily found in the southern Piedmont from Virginia to Alabama, with outliers in the Southern Blue Ridge of North Carolina and Tennessee.
Nations: US
States/Provinces: AL, GA, NC, SC, TN, VA
Plot Analysis Summary:
http://vegbank.org/natureserve/ELEMENT_GLOBAL.2.877425
Confidence Level: Moderate
Confidence Level Comments: No Data Available
Grank: GNR
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.1 Catawba Rosebay / Michaux''s Saxifrage - Flattened Oatgrass Felsic & Mafic Scrub & Grassland Macrogroup | M506 | 2.B.2.Nc.1 |
| Group | 2.B.2.Nc.1.f Willdenow''s Croton - Appalachian Stitchwort - Woolly Ragwort Piedmont Flatrock Group | G671 | 2.B.2.Nc.1.f |
| Alliance | A3962 Willdenow''s Croton - Appalachian Stitchwort - Fameflower species Piedmont Open Flatrock Alliance | A3962 | 2.B.2.Nc.1.f |
Concept Lineage: G668 merged into G671 (MP 7-16-13). G173 split into G670 & G671 (DFL 7-24-12)
Predecessors: No Data Available
Obsolete Names: No Data Available
Obsolete Parents: No Data Available
Synonomy: ? Diamorpha community (Quarterman et al. 1993)
? Diamorpha community (Burbanck and Platt 1964)
= Granitic Flatrock (Schafale and Weakley 1990)
? Type B (Baker 1956)
? Diamorpha community (Burbanck and Platt 1964)
= Granitic Flatrock (Schafale and Weakley 1990)
? Type B (Baker 1956)
- Baker, W. B. 1956. Some interesting plants of the granite outcrops of Georgia. Georgia Mineral Newsletter 9(1):10-19.
- Burbanck, M. P., and R. B. Platt. 1964. Granite outcrop communities of the Piedmont Plateau in Georgia. Ecology 45:292-306.
- Chafin, L. 2011. Georgia''s natural communities and associated rare plant and animal species: Thumbnail accounts. Based on "Guide to the Natural Communities of Georgia," by Edwards et al. 2013. University of Georgia Press. Georgia Nongame Conservation Section, Wildlife Resources Division, Georgia Department of Natural Resources. 125 pp.
- Coffey, J. C. 1964. A floristic study of the flat granitic outcrops of the lower Piedmont, South Carolina. M.S. thesis, University of South Carolina, Columbia.
- Faber-Langendoen, D., J. Drake, S. Gawler, M. Hall, C. Josse, G. Kittel, S. Menard, C. Nordman, M. Pyne, M. Reid, L. Sneddon, K. Schulz, J. Teague, M. Russo, K. Snow, and P. Comer, editors. 2010-2019a. Divisions, Macrogroups and Groups for the Revised U.S. National Vegetation Classification. NatureServe, Arlington, VA. plus appendices. [in preparation]
- Nelson, J. B. 1986. The natural communities of South Carolina: Initial classification and description. South Carolina Wildlife and Marine Resources Department, Division of Wildlife and Freshwater Fisheries, Columbia, SC. 55 pp.
- Quarterman, E., M. P. Burbanck, and D. J. Shure. 1993. Rock outcrop communities: Limestone, sandstone, and granite. Pages 35-86 in: W. H. Martin, S. G. Boyce, and A. C. Echternacht, editors. Biodiversity of the southeastern United States: Upland terrestrial communities. John Wiley and Sons, New York.
- Schafale, M. P., and A. S. Weakley. 1990. Classification of the natural communities of North Carolina. Third approximation. North Carolina Department of Environment, Health, and Natural Resources, Division of Parks and Recreation, Natural Heritage Program, Raleigh. 325 pp.
- Wharton, C. H. 1978. The natural environments of Georgia. Georgia Department of Natural Resources, Atlanta. 227 pp.