Print Report
A3962 Croton michauxii var. ellipticus - Minuartia glabra - Phemeranthus spp. Piedmont Open Flatrock Alliance
Type Concept Sentence: This vegetation 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. It is found on granitic domes and flatrocks in the southern Piedmont of the southern United States from Alabama to Virginia.
Common (Translated Scientific) Name: Willdenow''s Croton - Appalachian Stitchwort - Fameflower species Piedmont Open Flatrock Alliance
Colloquial Name: Southern Piedmont Open Granite Flatrock
Hierarchy Level: Alliance
Type Concept: This vegetation 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. Some examples may also have Cyperus granitophilus, Minuartia glabra, Minuartia uniflora (from southern North Carolina southwards), and other annuals, including Diamorpha smallii, which may have high cover in patches. This alliance 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. It is restricted to granitic domes and flatrocks in the southern Piedmont of the southern United States from Alabama to Virginia. Examples may include ephemeral pools, 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 ephemeral pools, 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 Burbank and Platt (1964).
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 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., with Diamorpha smallii having high cover in some examples. Some examples may also have Cyperus granitophilus, Minuartia glabra, Minuartia uniflora (from southern North Carolina southwards), and other annuals. This alliance also includes seepage areas with greater wetness which contain or are dominated by Portulaca smallii and Phemeranthus teretifolius (= Talinum teretifolium), with Lindernia monticola present in some occurrences.
Dynamics: No Data Available
Environmental Description: Examples of this vegetation occur in ephemeral pools, 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.
Geographic Range: Vegetation of this alliance is found in the southern Piedmont from Alabama to Virginia.
Nations: US
States/Provinces: AL, GA, NC, SC, VA
Plot Analysis Summary:
http://vegbank.org/natureserve/ELEMENT_GLOBAL.2.900013
Confidence Level: Moderate
Confidence Level Comments: No Data Available
Grank: GNR
Greasons: No Data Available
Concept Lineage: This new alliance unifies elements from two old alliances: A.1819 (2/3), and A.1920 (1/16). CEGL004298 was placed in proto A2075, but that is being changed.
Predecessors: No Data Available
Obsolete Names: No Data Available
Obsolete Parents: No Data Available
Synonomy: ? Diamorpha community (Burbanck and Platt 1964)
? Diamorpha community (Quarterman et al. 1993)
= Granitic Flatrock (Schafale and Weakley 1990)
? Type B (Baker 1956)
? Diamorpha community (Quarterman et al. 1993)
= 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, M. Hall, G. Kittel, S. Menard, C. Nordman, M. Pyne, M. Reid, M. Russo, K. Schulz, L. Sneddon, K. Snow, and J. Teague. 2013-2019b. Screening alliances for induction into the U.S. National Vegetation Classification: Part 1 - Alliance concept review. NatureServe, Arlington, VA.
- 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.