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A1920 Quercus stellata - Quercus marilandica / Schizachyrium scoparium Interior Acidic Bedrock Scrub Alliance

Type Concept Sentence: This alliance is dominated by Schizachyrium scoparium and other native warm-season perennial grasses with scattered trees, such as Quercus stellata and Quercus marilandica being the most common, often with Juniperus virginiana var. virginiana. It is found on exposed slopes and thin soil areas typically over shale or sandstone in the central United States.

Common (Translated Scientific) Name: Post Oak - Blackjack Oak / Little Bluestem Interior Acidic Bedrock Scrub Alliance

Colloquial Name: Central Interior Acidic Glade & Barrens

Hierarchy Level:  Alliance

Type Concept: Native grasses dominate stands of this alliance with scattered trees and shrubs, with Quercus stellata and Quercus marilandica being the most common trees, although Quercus velutina and Juniperus virginiana var. virginiana may often be present. Andropogon virginicus, Danthonia spicata, Dichanthelium spp., and Schizachyrium scoparium are the most abundant grasses. Rhus aromatica, Smilax bona-nox, Smilax glauca, Toxicodendron radicans, Ulmus alata, and Vaccinium arboreum make up the sparse to moderate shrub layer. Lichens (e.g., Cladonia spp.) and mosses are prominent on exposed rock. Stands of this alliance occur on exposed slopes and thin soil areas throughout its range in the central United States. The soil is absent to thin (0-40 cm) and somewhat rapidly to very rapidly drained. Exposed bedrock or fragments of parent material are common on or at the surface. Some associations are over various igneous materials, e.g., nepheline syenite in Arkansas. In Missouri, they occur on moderate to steep slopes of dissected drainages along major streams and mounds. Organic matter is low, and clay content can be quite high.

Diagnostic Characteristics: Grasslands or open woodlands dominated by Schizachyrium scoparium and other native warm-season perennial grasses with scattered broad-leaved deciduous trees, such as Quercus stellata, and Quercus marilandica sometimes with needle-leaved evergreen trees such as Juniperus virginiana var. virginiana. These glades and barrens occur in the central interior part of the United States from Illinois, Indiana, Ohio, and Kentucky west to Missouri, Arkansas, Oklahoma, and Kansas, on thin acidic soils over shale, sandstone, or siltstone (in Indiana). Acidic rock outcrops of shale or sandstone are often interspersed within these open woodlands or grasslands.

Rationale for Nominal Species or Physiognomic Features: No Data Available

Classification Comments: Similar vegetation on the Cumberland Plateau is classified as ~Schizachyrium scoparium - Danthonia sericea - Bigelowia nuttallii Cumberland Sandstone Grassland Alliance (A3474)$$.

Similar NVC Types: No Data Available
note: No Data Available
Physiognomy and Structure: This alliance includes grasslands dominated by Schizachyrium scoparium with scattered broad-leaved deciduous trees, or mixed broad-leaved deciduous trees with needle-leaved evergreen trees such as Juniperus virginiana var. virginiana. Graminoids dominate stands of this alliance with scattered trees and shrubs.

Floristics: This alliance includes grasslands dominated by Schizachyrium scoparium with scattered broad-leaved deciduous trees, or mixed broad-leaved deciduous trees with needle-leaved evergreen trees such as Juniperus virginiana var. virginiana. Graminoids dominate stands of this alliance with scattered trees and shrubs. Various combinations of Quercus spp. and Juniperus virginiana var. virginiana may be present, with Quercus stellata and Quercus marilandica being the most common trees, although Quercus velutina may often be present. Andropogon virginicus, Danthonia spicata, Dichanthelium spp., and Schizachyrium scoparium are the most abundant herbs. Some other herbs which may be found include Asclepias amplexicaulis, Carex spp., Castilleja coccinea, Coreopsis tripteris, Liatris spp., Rudbeckia spp., and Silphium spp. Rhus aromatica, Smilax bona-nox, Smilax glauca, Toxicodendron radicans, Ulmus alata, and Vaccinium arboreum make up the sparse to moderate shrub layer. Lichens (e.g., Cladonia spp.) and mosses are prominent on exposed rock.

Dynamics:  Fire, climate, native and livestock grazing and edaphic factors all played a role historically in maintaining an open structure in this vegetation. Loss of these natural processes often results in a decrease in native grass cover and increase in woody invaders. Threats to these communities include lack of fire, livestock grazing, and damage by feral hogs and off-road vehicles. The current range of this alliance has been reduced greatly from its historic extent.
Environmental Description:  Stands of this alliance occur on exposed slopes and thin soil areas throughout its range. The soil is absent to thin (0-40 cm) and somewhat rapidly to very rapidly drained. The parent material is variable but most typically shale or sandstone, with siltstone present in Indiana occurrences. Exposed bedrock or fragments of parent material are common on or at the surface. Most associations in this alliance occur over soils that are stony, shallow, and typically acidic, primarily consisting of weathered mineral matter, loess, and organic debris which collects in cracks and crevices of the bedrock. Some associations are over various igneous materials, e.g., nepheline syenite in Arkansas. In Missouri, they occur on moderate to steep slopes of dissected drainages along major streams and mounds. Organic matter is low, and clay content can be quite high. These soils are extremely susceptible to erosion and downslope migration, especially on steeper slopes and during periods of freeze-thaw. All these factors contribute to poor productivity and provide only shallow root penetration for vegetation. Although predominantly droughty and excessively drained, these sites can be seasonally wet; water is occasionally ponded in shallow depressions.
Geographic Range: This alliance is found in the central United States from Illinois, Indiana, Ohio, and Kentucky west to Missouri, Arkansas, Oklahoma, and Kansas.

Nations: US

States/Provinces:  AR, IL, IN, KS, KY, MO, OH, OK


Confidence Level: Low

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.2 Little Bluestem - Silky Oatgrass Acidic Scrub & Grassland Macrogroup M509 2.B.2.Nc.2
Group 2.B.2.Nc.2.b Little Bluestem - Silky Oatgrass Acidic Glade & Barrens Group G178 2.B.2.Nc.2.b
Alliance A1920 Post Oak - Blackjack Oak / Little Bluestem Interior Acidic Bedrock Scrub Alliance A1920 2.B.2.Nc.2.b
Association CEGL002242 Little Bluestem - Churchmouse Three-awn - Willdenow''s Croton / Lichens Wooded Grassland CEGL002242 2.B.2.Nc.2.b
Association CEGL002243 Little Bluestem - Indiangrass - Lanceleaf Tickseed - Willdenow''s Croton Wooded Grassland CEGL002243 2.B.2.Nc.2.b
Association CEGL002244 Little Bluestem - Yellow Stonecrop - Rock Spikemoss - Kiss-Me-Quick / Lichens Wooded Grassland CEGL002244 2.B.2.Nc.2.b
Association CEGL002391 Post Oak - Blackjack Oak / Little Bluestem Wooded Grassland CEGL002391 2.B.2.Nc.2.b
Association CEGL002428 Blackjack Oak - (Eastern Red-cedar) / Little Bluestem - Poverty Oatgrass Wooded Grassland CEGL002428 2.B.2.Nc.2.b
Association CEGL003756 Post Oak - Winged Elm - (Eastern Red-cedar) / Rough Dropseed - Ouachita Beebalm Woodland CEGL003756 2.B.2.Nc.2.b
Association CEGL004062 Blackjack Oak - Eastern Red-cedar / Little Bluestem - Orange-grass Wooded Grassland CEGL004062 2.B.2.Nc.2.b
Association CEGL005134 Post Oak - Blackjack Oak / Little Bluestem - Prairie Rosinweed Wooded Grassland CEGL005134 2.B.2.Nc.2.b
Association CEGL007814 Post Oak - (Shortleaf Pine) / Farkleberry / Big Bluestem - Late Purple Aster Wooded Grassland CEGL007814 2.B.2.Nc.2.b
Association CEGL007825 Ashe''s Blackjack Oak / Little Bluestem - Big Bluestem - Ouachita Beebalm / Lichens Novaculite Glade Wooded Grassland CEGL007825 2.B.2.Nc.2.b
Concept Lineage: Derived from old alliance A.1920. (pasted in from old alliance A.1920 with edits in track changes)

Predecessors: No Data Available

Obsolete Names: No Data Available

Obsolete Parents: No Data Available
Synonomy: >< Schizachyrium scoparium / Juniperus virginiana herbaceous alliance (Hoagland 1998a)
>< Schizachyrium scoparium herbaceous series (Hoagland 1997)
>< ID4a. Bluestem Tallgrass Prairie (Allard 1990)
? ID4b. Morse Clay Calcareous Prairie (Allard 1990)
? ID4c. Fleming Calcareous Prairie (Allard 1990)
? ID4e. Cook Mountain Calcareous Prairie (Allard 1990)
>< ID4f. Limestone Prairie (Allard 1990)
>< ID4g. Sandstone Prairie (Allard 1990)
? IE10a. Interior Upland Limestone Barren (Allard 1990)
? IE6c. Ouachita Novaculite Glade/Outcrop (Allard 1990)
Concept Author(s): C.W. Nordman, in Faber-Langendoen et al. (2013)

Author of Description: C. Nordman

Acknowledgements: The past work of D. Allard, T. Foti, and B. Hoagland is gratefully acknowledged.

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.
  • Carpenter, S. 1996. Limestone glade plant and butterfly survey. Unpublished final report to Ouachita National Forest, Tiak Ranger District. 4 pp. plus appendices.
  • DeSelm, H. R. 1988. The barrens of the western Highland Rim of Tennessee. Pages 199-219 in: D. H. Snyder, editor. Proceedings of the first annual symposium on the natural history of the lower Tennessee and Cumberland river valleys. Austin Peay St. University, Center for Field Biology, Clarksville, TN.
  • DeSelm, H. R. 1990. Flora and vegetation of some barrens of the eastern Highland Rim of Tennessee. Castanea 55:187-206.
  • Evers, R. A. 1955. Hill prairies of Illinois. Bulletin of the Illinois Natural History Survey 26(5):367-446.
  • 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.
  • Faber-Langendoen, D., and Midwest State Natural Heritage Program Ecologists. 1996. Terrestrial vegetation of the midwest United States. International classification of ecological communities: Terrestrial vegetation of the United States. The Nature Conservancy, Arlington, VA.
  • Fehrenbacher, J. B., J. D. Alexander, I. J. Jansen, R. A. Pope, M. A. Flock, W. F. Andrews, L. J. Bushue, J. W. Scott, and E. E. Voss. 1982. General soil map of Illinois, 1:500,000 scale. University of Illinois, College of Agriculture, Agricultural Experiment Station, and USDA Soil Conservation Service, Champaign, IL.
  • Fralish, J. S. 1987. Forest stand basal area and its relationship to individual soil and topographic factors in the Shawnee Hills. Transactions of the Illinois Academy of Science 80(3 and 4):183-194.
  • Heikens, A. L., K. A. West, and P. A. Robertson. 1994. Short-term response of chert and shale barrens vegetation to fire in southwestern Illinois. Castanea 59(3):274-285.
  • Hoagland, B. W. 1997. Preliminary plant community classification for Oklahoma. Unpublished draft document, version 35629. University of Oklahoma, Oklahoma Natural Heritage Inventory, Norman. 47 pp.
  • Hoagland, B. W. 1998a. Classification of Oklahoma vegetation types. Working draft. University of Oklahoma, Oklahoma Natural Heritage Inventory, Norman. 43 pp.
  • Homoya, M. A. 1994. Indiana barrens: Classification and description. Castanea 59(3):204-213.
  • Hutchison, M. D. 1994. The barrens of the Midwest: An historical perspective. Castanea 59(3):195-203.
  • Nelson, P. W. 1985. The terrestrial natural communities of Missouri. Missouri Natural Areas Committee, Jefferson City. 197 pp. Revised edition, 1987.
  • Voigt, J. W., and R. H. Mohlenbrock. 1964. Plant communities of southern Illinois. Southern Illinois University Press, Carbondale. 202 pp.