NatureServe Explorer logo.An Online Encyclopedia of Life
Search
Ecological Association Comprehensive Report: Record 1 of 1 selected.
See All Search Results    View Glossary
<< Previous | Next >>

Fraxinus americana - Juniperus virginiana / Talinum teretifolium - Polygonum tenue - Opuntia humifusa Wooded Grassland
Translated Name: White Ash - Eastern Red-cedar / Quill Fameflower - Pleatleaf Knotweed - Eastern Prickly-pear Wooded Grassland
Common Name: Piedmont Mafic Barrens
Unique Identifier: CEGL006294
Classification Approach: International Vegetation Classification (IVC)
Summary: This community is known only from scattered mafic outcrops in the northern Virginia Piedmont. It occupies exposed, xeric bedrock exposures and has a mixed physiognomy best characterized as herbaceous with scattered, stunted trees. Fraxinus americana and Juniperus virginiana are the most typical woody plants. Dominant and diagnostic lower-strata species include Opuntia humifusa, Talinum teretifolium, Polygonum tenue, Krigia virginica, Carex pensylvanica, and Danthonia spicata.



Classification

Classification Confidence: Moderate
Classification Comments: It is unclear whether similar vegetation occurring on Bald Knob, a mafic monadnock in the southern Virginia Piedmont, belongs to this type. Also closely related (at least in physical setting) are the Diabase Glades of North Carolina, but based on the available information, they appear to be floristically distinct. None of the characteristic herbaceous species are mentioned in the descriptions provided by North Carolina.

Vegetation Hierarchy
Class 2 - Shrub & Herb Vegetation
Subclass 2.B - Temperate & Boreal Grassland & Shrubland
Formation 2.B.2 - Temperate Grassland & Shrubland
Division 2.B.2.Nc - Eastern North American Grassland & Shrubland
Macrogroup Appalachian Rocky Felsic & Mafic Scrub & Grassland
Group Appalachian Mafic Glade
Alliance Appalachian Mafic-Circumneutral Barrens

This is the revised vegetation hierarchy. For more information see Classification Sources and usnvc.org.



Related Concepts from Other Classifications

Other Related Concepts
Related Concept Name: Fraxinus americana - Juniperus virginiana / Talinum teretifolium - Polygonum tenue - Opuntia humifusa Wooded Herbaceous Vegetation
Relationship: ? - Undetermined
Reference: Fleming, Gary P. Personal communication. Ecologist, Virginia Department of Conservation and Recreation, Division of Natural Heritage, Richmond, VA.
Related Concept Name: Fraxinus americana / Opuntia humifusa var. humifusa - Carex pensylvanica - Talinum teretifolium - Polygonum tenue Sparse Shrubland
Relationship: ? - Undetermined
Reference: Fleming, G. P. 2002b. Preliminary classification of Piedmont & Inner Coastal Plain vegetation types in Virginia. Natural Heritage Technical Report 02-14. Virginia Department of Conservation and Recreation, Division of Natural Heritage, Richmond. 29 pp.
Relationship: ? - Undetermined
Reference: Fleming, Gary P. Personal communication. Ecologist, Virginia Department of Conservation and Recreation, Division of Natural Heritage, Richmond, VA.
Related Concept Name: Schizachyrium scoparium - Opuntia humifusa - Talinum mengesii - Minuartia glabra Herbaceous Vegetation
Relationship: = - Equivalent
Reference: Fleming, G. P., and K. D. Patterson. 2003. Preliminary vegetation classification for the National Capitol Region parks. Regional (VA-WVA-MD-DC) analysis prepared for NatureServe and USGS-NPS Vegetation Mapping Program, March 2003. Virginia Department of Conservation and Recreation, Division of Natural Heritage, Richmond.
Related Concept Name: Low-Elevation Basic Outcrop Barren
Relationship: B - Broader
Reference: Fleming, G. P., P. P. Coulling, D. P. Walton, K. M. McCoy, and M. R. Parrish. 2001. The natural communities of Virginia: Classification of ecological community groups. First approximation. Natural Heritage Technical Report 01-1. Virginia Department of Conservation and Recreation, Division of Natural Heritage, Richmond, VA. 76 pp.

Ecological Systems Placement

Ecological Systems Placement
Ecological System Unique ID Ecological System Name
CES202.268 Piedmont Hardpan Woodland and Forest
CES202.328 Southern Piedmont Glade and Barrens


NatureServe Conservation Status
Global Status: G1 (25Jan2005)
Rounded Global Status: G1 - Critically Imperiled
Reasons: There are only 8 known occurrences of this community rangewide. Each occurrence is very small, usually less than an acre, and none are protected. There are probably fewer than 10 acres rangewide. All occurrences are in two ecoregion subsections in the northern Piedmont of Virginia, on diabase or metabasalt outcrops. This community has probably always been rare; some loss of acreage has occurred due to road construction, and several sites have been degraded by invasion of weedy species from nearby disturbed areas. This community is highly threatened by quarrying and road construction.

Distribution
Color legend for Distribution Map
United States Distribution: VA
Global Distribution: United States
Global Range: This type is apparently restricted to the northern Piedmont of Virginia.

U.S. Forest Service Ecoregions
Domain Name: Humid Temperate Domain
Division Name: Subtropical Division
Province Name: Southeastern Mixed Forest Province
Province Code: 231 Occurrence Status: Confident or certain
Section Name: Southern Appalachian Piedmont Section
Section Code: 231A Occurrence Status: Confident or certain


Vegetation

Vegetation Summary: This small-patch community exhibits mixed physiognomy, occurring as a patch-mosaic of lichen and moss mats, herbs, and shrubs or stunted trees. Wooded herbaceous is probably the best descriptor of the physiognomy. Trees are usually stunted and widely spaced, with Fraxinus americana and Juniperus virginiana usually the principal species. Minor trees and shrubs include Pinus virginiana, Carya glabra, Quercus prinus, Celtis occidentalis, Celtis tenuifolia, and Rhus aromatica. The herb layer consists of mixed forbs, grasses, and Opuntia humifusa rooted on thin-soiled shelves, moss mats, and crevices. Constant species include Carex pensylvanica (dominant), Danthonia spicata (dominant), Talinum teretifolium, Polygonum tenue, Krigia virginica, Triodanis perfoliata, and Schizachyrium scoparium. Less constant but nevertheless characteristic herbs include Bulbostylis capillaris, Cheilanthes lanosa, Cyperus lupulinus, Eragrostis capillaris, Fimbristylis annua, Isanthus brachiatus, Muhlenbergia capillaris, Panicum philadelphicum, Scutellaria parvula var. missouriensis (= Scutellaria leonardii), Trichostema setaceum, and Trifolium virginicum. Many other species occur at low cover and constancy. Lichens and mosses, including Xanthoparmelia sp., Grimmia laevigata, Polytrichum sp., and Dicranum sp., are abundant on exposed outcrop surfaces.

Vegetation Composition (incomplete)
Species Name Rounded Global Status Growth Form Stratum Charact-
eristic
Dominant Constant
Cover Class %
Con-
stancy
%
Juniperus virginiana G1 Needle-leaved tree Tree canopy  
 
 
Opuntia humifusa G1 Succulent shrub Short shrub/sapling    
 
 
Trifolium virginicum G1 Flowering forb Herb (field)    
 
 
Cyperus squarrosus G1 Graminoid Herb (field)    
 
 
Fimbristylis annua G1 Graminoid Herb (field)    
 
 
Muhlenbergia capillaris G1 Graminoid Herb (field)    
 
 


At-Risk Species Reported for this Association
Scientific Name
  (Common Name)
NatureServe Global Status U.S. Endangered Species Act Status
Trifolium virginicum
  (Kate's Mountain Clover)
G3  


Environmental Setting

Wetland Indicator: N
Environmental Summary: This vegetation type is restricted to exposed outcrops of diabase, metabasalt, and perhaps other mafic rocks in the northern Virginia Piedmont. In the northern Virginia Culpeper Basin, outcrops of fine-grained Triassic diabase are usually exposed by stream incision. Metabasalt outcrops are located on western Piedmont foothills of the Blue Ridge and are represented by resistant ledges and cliffs. Outcrops supporting this community vary from steeply dipping to nearly level ("flatrocks"). On steeper terrain, habitats are typically south- to west-facing. Soil development is limited to depositional crevices and thin veneers of silt and gravel on ledges. Samples collected from three plots were strongly to moderately acidic, with moderately high Ca, Mg, and Mn levels. Most occurrences exhibit periods of ephemeral vernal seepage on outcrop surfaces and moss mats. A closely related community type in North Carolina (Diabase Glade) occurs on xeric, acidic to neutral, purple brown, Lithic Hapludalfs with exposed bedrock.


Dynamic Processes

Dynamics: The massive outcrops supporting this community type effectively limit the normal establishment and development of trees. Although periodic drought stress limits some weeds, the shrub Symphoricarpos orbiculatus, introduced from the western U.S., has become invasive in one occurrence. Ruderal weeds such as Veronica arvensis, Barbarea vulgaris, and Verbascum thapsus can also become problematic, especially in wet years.


Plot Sampling & Classification Analysis

Plots stored in VegBank


Authors/Contributors
Concept Author(s): Eastern Ecology Group
Element Description Edition Date: 25Jan2005
Element Description Author(s): G.P. Fleming
NatureServe Conservation Status Factors Edition Date: 25Jan2005
NatureServe Conservation Status Factors Author(s): C. Reschke, mod. G.P. Fleming

Ecological data developed by NatureServe and its network of natural heritage programs (see Local Programs) and other contributors and cooperators (see Sources).


References
  • Eastern Ecology Working Group of NatureServe. No date. International Ecological Classification Standard: International Vegetation Classification. Terrestrial Vegetation. NatureServe, Boston, MA.

  • Fleming, G. P. 2002b. Preliminary classification of Piedmont & Inner Coastal Plain vegetation types in Virginia. Natural Heritage Technical Report 02-14. Virginia Department of Conservation and Recreation, Division of Natural Heritage, Richmond. 29 pp.

  • Fleming, G. P., P. P. Coulling, D. P. Walton, K. M. McCoy, and M. R. Parrish. 2001. The natural communities of Virginia: Classification of ecological community groups. First approximation. Natural Heritage Technical Report 01-1. Virginia Department of Conservation and Recreation, Division of Natural Heritage, Richmond, VA. 76 pp.

  • Fleming, G. P., and K. D. Patterson. 2003. Preliminary vegetation classification for the National Capitol Region parks. Regional (VA-WVA-MD-DC) analysis prepared for NatureServe and USGS-NPS Vegetation Mapping Program, March 2003. Virginia Department of Conservation and Recreation, Division of Natural Heritage, Richmond.

  • Fleming, G. P., and K. D. Patterson. 2009b. Classification of selected Virginia montane wetland groups. In-house analysis, December 2009. Virginia Department of Conservation and Recreation, Division of Natural Heritage, Richmond.

  • Fleming, G. P., and K. D. Patterson. 2011a. Natural communities of Virginia: Ecological groups and community types. Natural Heritage Technical Report 11-07. Virginia Department of Conservation and Recreation, Division of Natural Heritage, Richmond. 34 pp.

  • Fleming, Gary P. Personal communication. Ecologist, Virginia Department of Conservation and Recreation, Division of Natural Heritage, Richmond, VA.

  • Grossman, D. H., K. Lemon Goodin, and C. L. Reuss, editors. 1994. Rare plant communities of the conterminous United States: An initial survey. The Nature Conservancy. Arlington, VA. 620 pp.


Use Guidelines and Citation

The Small Print: Trademark, Copyright, Citation Guidelines, Restrictions on Use, and Information Disclaimer.

Note: All species and ecological community data presented in NatureServe Explorer at http://explorer.natureserve.org were updated to be current with NatureServe's central databases as of November 2016.
Note: This report was printed on

Trademark Notice: "NatureServe", NatureServe Explorer, The NatureServe logo, and all other names of NatureServe programs referenced herein are trademarks of NatureServe. Any other product or company names mentioned herein are the trademarks of their respective owners.

Copyright Notice: Copyright © 2017 NatureServe, 4600 N. Fairfax Dr., 7th Floor, Arlington Virginia 22203, U.S.A. All Rights Reserved. Each document delivered from this server or web site may contain other proprietary notices and copyright information relating to that document. The following citation should be used in any published materials which reference the web site.

Citation for data on website including State Distribution, Watershed, and Reptile Range maps:
NatureServe. 2017. NatureServe Explorer: An online encyclopedia of life [web application]. Version 7.1. NatureServe, Arlington, Virginia. Available http://explorer.natureserve.org. (Accessed:

Citation for Bird Range Maps of North America:
Ridgely, R.S., T.F. Allnutt, T. Brooks, D.K. McNicol, D.W. Mehlman, B.E. Young, and J.R. Zook. 2003. Digital Distribution Maps of the Birds of the Western Hemisphere, version 1.0. NatureServe, Arlington, Virginia, USA.

Acknowledgement Statement for Bird Range Maps of North America:
"Data provided by NatureServe in collaboration with Robert Ridgely, James Zook, The Nature Conservancy - Migratory Bird Program, Conservation International - CABS, World Wildlife Fund - US, and Environment Canada - WILDSPACE."

Citation for Mammal Range Maps of North America:
Patterson, B.D., G. Ceballos, W. Sechrest, M.F. Tognelli, T. Brooks, L. Luna, P. Ortega, I. Salazar, and B.E. Young. 2003. Digital Distribution Maps of the Mammals of the Western Hemisphere, version 1.0. NatureServe, Arlington, Virginia, USA.

Acknowledgement Statement for Mammal Range Maps of North America:
"Data provided by NatureServe in collaboration with Bruce Patterson, Wes Sechrest, Marcelo Tognelli, Gerardo Ceballos, The Nature Conservancy-Migratory Bird Program, Conservation International-CABS, World Wildlife Fund-US, and Environment Canada-WILDSPACE."

Citation for Amphibian Range Maps of the Western Hemisphere:
IUCN, Conservation International, and NatureServe. 2004. Global Amphibian Assessment. IUCN, Conservation International, and NatureServe, Washington, DC and Arlington, Virginia, USA.

Acknowledgement Statement for Amphibian Range Maps of the Western Hemisphere:
"Data developed as part of the Global Amphibian Assessment and provided by IUCN-World Conservation Union, Conservation International and NatureServe."

NOTE: Full metadata for the Bird Range Maps of North America is available at:
http://www.natureserve.org/library/birdDistributionmapsmetadatav1.pdf.

Full metadata for the Mammal Range Maps of North America is available at:
http://www.natureserve.org/library/mammalsDistributionmetadatav1.pdf.

Restrictions on Use: Permission to use, copy and distribute documents delivered from this server is hereby granted under the following conditions:
  1. The above copyright notice must appear in all copies;
  2. Any use of the documents available from this server must be for informational purposes only and in no instance for commercial purposes;
  3. Some data may be downloaded to files and altered in format for analytical purposes, however the data should still be referenced using the citation above;
  4. No graphics available from this server can be used, copied or distributed separate from the accompanying text. Any rights not expressly granted herein are reserved by NatureServe. Nothing contained herein shall be construed as conferring by implication, estoppel, or otherwise any license or right under any trademark of NatureServe. No trademark owned by NatureServe may be used in advertising or promotion pertaining to the distribution of documents delivered from this server without specific advance permission from NatureServe. Except as expressly provided above, nothing contained herein shall be construed as conferring any license or right under any NatureServe copyright.
Information Warranty Disclaimer: All documents and related graphics provided by this server and any other documents which are referenced by or linked to this server are provided "as is" without warranty as to the currentness, completeness, or accuracy of any specific data. NatureServe hereby disclaims all warranties and conditions with regard to any documents provided by this server or any other documents which are referenced by or linked to this server, including but not limited to all implied warranties and conditions of merchantibility, fitness for a particular purpose, and non-infringement. NatureServe makes no representations about the suitability of the information delivered from this server or any other documents that are referenced to or linked to this server. In no event shall NatureServe be liable for any special, indirect, incidental, consequential damages, or for damages of any kind arising out of or in connection with the use or performance of information contained in any documents provided by this server or in any other documents which are referenced by or linked to this server, under any theory of liability used. NatureServe may update or make changes to the documents provided by this server at any time without notice; however, NatureServe makes no commitment to update the information contained herein. Since the data in the central databases are continually being updated, it is advisable to refresh data retrieved at least once a year after its receipt. The data provided is for planning, assessment, and informational purposes. Site specific projects or activities should be reviewed for potential environmental impacts with appropriate regulatory agencies. If ground-disturbing activities are proposed on a site, the appropriate state natural heritage program(s) or conservation data center can be contacted for a site-specific review of the project area (see Visit Local Programs).

Feedback Request: NatureServe encourages users to let us know of any errors or significant omissions that you find in the data through (see Contact Us). Your comments will be very valuable in improving the overall quality of our databases for the benefit of all users.

Copyright 2017
NatureServe
Version 7.1 (2 February 2009)
Data last updated: November 2016