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A0930 Rubus allegheniensis - Rubus canadensis Shrubland Alliance

Type Concept Sentence: This alliance includes areas dominated by Rubus allegheniensis, Rubus canadensis, Rubus idaeus ssp. strigosus, and Prunus pensylvanica at high elevations in the Southern Blue Ridge, on grassy balds, in areas where the balsam woolly adelgid has caused Abies fraseri death, or other disturbed areas such as landslide scars that create open conditions.


Common (Translated Scientific) Name: Allegheny Blackberry - Smooth Blackberry Shrubland Alliance

Colloquial Name: Southern Appalachian Blackberry Shrubland

Hierarchy Level:  Alliance

Type Concept: This alliance encompasses Rubus-dominated areas at high elevations in the Southern Blue Ridge, as well as related stands dominated by Prunus pensylvanica. This includes grassy balds (open montane grasslands), areas where the balsam woolly adelgid has caused Abies fraseri death, or other disturbed areas such as landslide scars that create open conditions. Stands of this alliance are dominated by Rubus allegheniensis, Rubus canadensis, and Rubus idaeus ssp. strigosus. Examples in otherwise grassy balds may also contain trace amounts of other species from adjacent grasslands, such as Athyrium filix-femina ssp. asplenioides, Agrostis perennans, Angelica triquinata, Carex debilis var. rudgei, Carex brunnescens, Carex intumescens, and Rumex acetosella (exotic). Successional stands at high elevation resulting from severe disturbance of spruce-fir forests (i.e., balsam woolly adelgid-affected stands), as well as exposed sites with other frequent, natural disturbance (such as shrub invasion of grazed fire meadows), may contain dense Athyrium filix-femina ssp. asplenioides and Solidago glomerata (on more protected sites). Scattered living trees and shrubs of Amelanchier laevis, Betula alleghaniensis, Picea rubens, Prunus pensylvanica, and Sorbus americana may occur.

Diagnostic Characteristics: Distinctive shrublands dominated primarily by Rubus allegheniensis and/or Rubus canadensis, restricted to higher elevations in the Southern Appalachians.

Rationale for Nominal Species or Physiognomic Features: No Data Available

Classification Comments: The associations in this alliance can, to varying degrees, be regarded as "semi-natural" or even "ruderal" in that their presence may be related to successional situations following the cessation of grazing, the death of Abies fraseri, intense fires, as well as other possible factors and situations. The placement of the alliance in this group as opposed to a ruderal shrubland group should be investigated. In the Southern Appalachians of North Carolina and Tennessee, Prunus pensylvanica often forms an open low-canopy layer (<50% cover). In areas such as Shining Rock Wilderness and parts of the Great Smoky Mountains, fires were started after logging had taken place and the intensity of the fires, due to the accumulated slash, burned down nearly to mineral soil. These areas do not have as much coarse woody debris from downed spruce or fir and often have a canopy approaching that of a woodland with sparse cover of Prunus pensylvanica and Sorbus americana.

Similar NVC Types: No Data Available
note: No Data Available

Physiognomy and Structure: This high-elevation Appalachian bald vegetation is dominated by Rubus allegheniensis and Rubus canadensis. Herbaceous plants typical of grassy balds may be found in this vegetation, and scattered living trees and shrubs of Amelanchier laevis, Betula alleghaniensis, Picea rubens, Prunus pensylvanica, and Sorbus americana may occur.

Floristics: Stands of this alliance are dominated by Rubus allegheniensis, Rubus canadensis, and Rubus idaeus ssp. strigosus. Examples in otherwise grassy balds may also contain trace amounts of other species from adjacent grasslands, such as Athyrium filix-femina ssp. asplenioides, Agrostis perennans, Angelica triquinata, Carex debilis var. rudgei, Carex brunnescens, Carex intumescens (= var. fernaldii), and Rumex acetosella (exotic). Successional stands at high elevation resulting from severe disturbance of spruce-fir forests (i.e., balsam woolly adelgid-affected stands), as well as exposed sites with other frequent, natural disturbance (such as shrub invasion of grazed fire meadows), may contain dense Athyrium filix-femina ssp. asplenioides and Solidago glomerata (on more protected sites). Scattered living trees and shrubs of Amelanchier laevis, Betula alleghaniensis, Picea rubens, Prunus pensylvanica, and Sorbus americana may occur.

Dynamics:  Strong winds, high rainfall, frequent fog, shallow, rocky soils, and extremes of temperature and moisture are characteristic of these environments, and keep the areas from becoming dominated by deciduous trees. Successional stands at high elevation resulting from severe disturbance of spruce-fir forests (i.e., balsam woolly adelgid-affected stands), as well as exposed sites with other frequent, natural disturbance (such as shrub invasion of grazed fire meadows), may contain dense Athyrium filix-femina ssp. asplenioides and Solidago glomerata (on more protected sites).

Environmental Description:  These grasslands occur at high elevations (usually above 1200-1500 m [4000-5000 feet]) in the Southern Blue Ridge, often on south- to southwest-facing domes, ridgetops and gentle slopes. Strong winds, high rainfall, frequent fog, shallow, rocky soils, and extremes of temperature and moisture are characteristic of these environments. This alliance may occur intermixed with grassy balds (which are open montane grasslands), in areas where the balsam woolly adelgid has caused Abies fraseri death, or in other disturbed areas such as landslide scars that create open conditions.

Geographic Range: Stands are found in the Southern Appalachians and adjacent Central Appalachians from Tennessee, North Carolina, and Virginia.

Nations: US

States/Provinces:  NC, TN, VA




Confidence Level: Moderate

Confidence Level Comments: No Data Available

Grank: GNR

Greasons: No Data Available


Concept Lineage: equivalent to A.930

Predecessors: No Data Available

Obsolete Names: No Data Available

Obsolete Parents: No Data Available

Synonomy: >< ID9a. Grass Bald (Allard 1990)

Concept Author(s): S. Simon, G. Kauffman, D.M. Danley, in Faber-Langendoen et al. (2013)

Author of Description: M. Pyne

Acknowledgements: No Data Available

Version Date: 09-26-14

  • Allard, D. J. 1990. Southeastern United States ecological community classification. Interim report, Version 1.2. The Nature Conservancy, Southeast Regional Office, Chapel Hill, NC. 96 pp.
  • Crandall, D. L. 1958. Ground vegetation patterns of the spruce-fir area of the Great Smoky Mountains National Park. Ecological Monographs 28:337-360.
  • 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.
  • Feldcamp, S. M. 1984. Revegetation of upper elevation debris slide scars on Mt. LeConte in the Great Smoky Mountains National Park. M.S. thesis, University of Tennessee, Knoxville. 106 pp.
  • 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.