Print Report

G340 Polypodium spp. - Umbilicaria spp. - Danthonia spicata Talus, Bluff & Rock Vegetation Group

Type Concept Sentence: This vegetation comprises sparse and lichen-dominated vegetation occurring on talus slopes and boulderfields, and on erosional bluffs on lakes, rivers, and coastal settings in the eastern and midwestern U.S. and Canada.

Common (Translated Scientific) Name: Polypody species - Rocktripe Lichen species - Poverty Oatgrass Talus, Bluff & Rock Vegetation Group

Colloquial Name: Northeastern Erosional Bluff Vegetation

Hierarchy Level:  Group

Type Concept: This group encompasses sparse vascular or nonvascular vegetation on steep, unconsolidated substrates in temperate eastern North America. The two main substrate types are talus slopes and erosional bluffs. Vegetation varies with substrate character and chemistry. Open talus features sparse vascular vegetation with Dryopteris marginalis, Parthenocissus quinquefolia, Polypodium spp., Ribes spp., Toxicodendron radicans, or Toxicodendron rydbergii characteristic, and/or areas dominated by macrolichens. Characteristic foliose and fruticose macrolichen genera include Umbilicaria, Lasallia, Cladonia, and Stereocaulon. Crustose lichens are also common. Scattered small trees may be present, including Juniperus virginiana. Vegetation on erosional bluffs is sparse and highly variable. Species in these habitats tolerate disturbance, and can include Carex scoparia, Comptonia peregrina, Danthonia spicata, Dichanthelium depauperatum, Equisetum arvense, Equisetum hyemale, Impatiens capensis, Oenothera biennis, Polygonella articulata, Schizachyrium scoparium, Solidago nemoralis, and non-native weeds including Tussilago farfara.

Diagnostic Characteristics: Sparse vegetation of talus slopes, boulderfields, and erosional slopes; rock chemistry and species composition vary.

Rationale for Nominal Species or Physiognomic Features: No Data Available

Classification Comments: More data are needed to better circumscribe and describe this group.

Similar NVC Types: No Data Available
note: No Data Available
Physiognomy and Structure: Vegetation is sparse and primarily herb-dominated. Nonvascular plants may also be prominent, especially on talus and boulderfields. Shrubs and small trees are occasional. Unvegetated substrate is common on erosional bluffs.

Floristics: Open talus features sparse vascular vegetation with Dryopteris marginalis, Parthenocissus quinquefolia, Polypodium spp., Ribes spp., Toxicodendron radicans, or Toxicodendron rydbergii characteristic, and/or areas dominated by macrolichens. Characteristic foliose and fruticose macrolichen genera include Umbilicaria, Lasallia, Cladonia, and Stereocaulon. Crustose lichens are also common. Scattered small trees may be present. Vegetation on erosional bluffs is sparse and highly variable. Species in these habitats tolerate disturbance and can include Carex scoparia, Comptonia peregrina, Danthonia spicata, Dichanthelium clandestinum (= Panicum clandestinum), Dichanthelium depauperatum (= Panicum depauperatum), Equisetum arvense, Equisetum hyemale, Impatiens capensis, Oenothera biennis, Polygonella articulata, Schizachyrium scoparium, Solidago nemoralis, and non-native weeds including Tussilago farfara.

Dynamics:  The open character of the vegetation on talus and boulderfields is maintained by exposure to wind, temperature fluctuations, and movement of unstable substrate downslope. Freeze-thaw cycles allow water to permeate bedrock above cliffs, resulting in fracturing of rock that accumulates on and at the base of the slope. Frequent natural disturbance caused by soil slumping of unstable unconsolidated sediments is characteristic of erosional bluffs. Additional processes here include wave action, flood scour, ice-scour, and exposure to storms.
Environmental Description:  Climate: North-temperate. Soil/substrate/hydrology: The unconsolidated substrate contributes to spatially and temporally variable vegetation. On talus, small pockets among the rocks provide rooting substrates; on bluffs, plants have more rooting sites available, but they are subject to erosion or slumping.
Geographic Range: This group ranges from New England and adjacent Canada west to the Great Lakes and northern Minnesota, south through the Appalachians and Piedmont (occasional in the Atlantic Coastal Plain), and west across the Cumberland Plateau and Interior Low Plateau to the Ozarks.

Nations: CA,US

States/Provinces:  AR, CT, GA, IA, IL, IN, KY, MA, MB, MD, ME, MI, MN, MO, MS, NB, NC, NH, NJ, NS, NY, OH, OK, ON, PA, QC, RI, SC, TN, TX, VA, VT, WI, WV


Confidence Level: Low

Confidence Level Comments: No Data Available
Grank: GNR

Greasons: No Data Available
Type Name Database Code Classification Code
Class 6 Open Rock Vegetation Class C06 6
Subclass 6.B Temperate & Boreal Open Rock Vegetation Subclass S04 6.B
Formation 6.B.1 Temperate & Boreal Cliff, Scree & Other Rock Vegetation Formation F034 6.B.1
Division 6.B.1.Na Eastern North American Temperate Cliff, Scree & Rock Vegetation Division D051 6.B.1.Na
Macrogroup 6.B.1.Na.1 Shrubby Fivefingers - Rock Polypody / Cup Lichen species Eastern North American Cliff & Rock Vegetation Macrogroup M111 6.B.1.Na.1
Group 6.B.1.Na.1.a Polypody species - Rocktripe Lichen species - Poverty Oatgrass Talus, Bluff & Rock Vegetation Group G340 6.B.1.Na.1.a
Alliance A3992 Eastern North American Erosional Bluff Alliance A3992 6.B.1.Na.1.a
Concept Lineage: No Data Available

Predecessors: No Data Available

Obsolete Names: No Data Available

Obsolete Parents: No Data Available
Synonomy: > Erosional River Bluff + Open Talus (Thompson and Sorenson 2000)
Concept Author(s): S.C. Gawler, D. Faber-Langendoen, and S.E. Menard, in Faber-Langendoen et al. (2011)

Author of Description: S.C. Gawler and L.A. Sneddon

Acknowledgements: No Data Available

Version Date: 05-06-15
  • 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]
  • Thompson, E. H., and E. R. Sorenson. 2000. Wetland, woodland, wildland: A guide to the natural communities of Vermont. The Nature Conservancy and the Vermont Department of Fish and Wildlife. University Press of New England, Hanover, NH. 456 pp.