Print Report

A3212 Juniperus ashei Woodland Alliance

Type Concept Sentence: This alliance includes needle-leaved evergreen woodlands characterized by Juniperus ashei occurring on calcareous substrates, with shallow, rocky soils, often with much exposed bedrock in the Edwards Plateau of Texas and adjacent regions, such as the Arbuckle Mountains of Oklahoma and the Stockton Plateau of Texas


Common (Translated Scientific) Name: Ashe''s Juniper Woodland Alliance

Colloquial Name: Ashe''s Juniper Woodland

Hierarchy Level:  Alliance

Type Concept: This alliance includes needle-leaved evergreen woodlands characterized by Juniperus ashei occurring on calcareous substrates, with shallow, rocky soils, often with much exposed bedrock in the Edwards Plateau of Texas and adjacent regions, such as the Arbuckle Mountains of Oklahoma and the Stockton Plateau of Texas. Associated species include evergreen oaks Quercus fusiformis, Quercus vaseyana, deciduous oaks Quercus sinuata var. breviloba and Quercus buckleyi, and other junipers and pines, including Pinus remota and Juniperus pinchotii, as well as Mahonia trifoliolata, Bouteloua curtipendula, Carex planostachys, Celtis laevigata var. reticulata, Diospyros texana, Fraxinus albicans, Lespedeza texana, Nolina texana, Toxicodendron pubescens, Rhus virens, Schizachyrium scoparium, and Yucca rupicola. Occurrences in the Arbuckle Mountains of Oklahoma have a grassy understory dominated by Schizachyrium scoparium. Climate and edaphic factors are thought to play an important role in maintaining these woodlands. Diagnostic criteria include a mostly needle-leaved canopy with Juniperus ashei as a characteristic species, occurring on calcareous substrates, with shallow, rocky soils, often with much exposed bedrock, places where Juniperus ashei is expected to be naturally dominant, in the Edwards Plateau and adjacent regions of Texas and Oklahoma.

Diagnostic Characteristics: Diagnostic criteria include a mostly needle-leaved canopy with Juniperus ashei as a characteristic species, occurring on calcareous substrates, with shallow, rocky soils, often with much exposed bedrock, places where Juniperus ashei is expected to be naturally dominant, in the Edwards Plateau and adjacent regions of Texas and Oklahoma.

Rationale for Nominal Species or Physiognomic Features: No Data Available

Classification Comments: This alliance is closely related to and shares many species with the other alliances in this group (G126). Differences between them are related to the dominance of those species and their growth form (broad-leaved subevergreen, needle-leaved evergreen, or deciduous). The prevalence of Juniperus ashei has likely increased since presettlement times in some areas of central Texas. This is speculated to have resulted from several factors including overgrazing and altered fire regimes. As a result, it may be difficult to distinguish juniper-invaded habitats from areas where juniper was naturally a dominant component of the vegetation. This alliance is restricted to shallow, rocky soils, places where Juniperus ashei is expected to be naturally dominant. Areas with deeper soils are more likely to support invasive Juniperus ashei, especially following disturbance or alteration of natural processes, such as protection from fire. There may be undescribed associations related to this alliance. More information is needed to flesh out detailed floristic, environment, and range.

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

Physiognomy and Structure: This alliance includes short-statured needle-leaved evergreen woodlands.

Floristics: This alliance includes needle-leaved evergreen woodlands characterized by Juniperus ashei. Associated species include evergreen oaks Quercus fusiformis, Quercus vaseyana (= Quercus pungens var. vaseyana), deciduous oaks Quercus sinuata var. breviloba and Quercus buckleyi, and other junipers and pines, including Pinus remota and Juniperus pinchotii, as well as Mahonia trifoliolata (= Berberis trifoliolata), Bouteloua curtipendula, Carex planostachys, Celtis laevigata var. reticulata (= Celtis reticulata), Diospyros texana, Fraxinus albicans (= Fraxinus texensis), Lespedeza texana, Nolina texana, Toxicodendron pubescens (= Rhus toxicodendron), Rhus virens, Schizachyrium scoparium, and Yucca rupicola. Occurrences in the Arbuckle Mountains of Oklahoma have a grassy understory dominated by Schizachyrium scoparium. Occurrences in the western Edwards Plateau and Stockton Plateau in Texas may have a mixture of southwestern shrubs, such as Acacia berlandieri, Acacia roemeriana, Condalia viridis, Forestiera reticulata, Jatropha dioica, and Salvia ballotiflora. Graminoids include Bouteloua curtipendula, Carex planostachys, Schizachyrium scoparium, Dichanthelium pedicellatum, Erioneuron pilosum, Poa bigelovii, and Vulpia octoflora.

Dynamics:  Climate and edaphic factors are thought to play an important role in maintaining these woodlands. Like all dry slope woodland types containing Juniperus ashei, it is threatened by brush clearing, a practice currently being promoted for watershed conservation.

Environmental Description:  Woodlands in this alliance generally occur on calcareous substrates, with shallow, rocky soils, often with much exposed bedrock and lichen coverage.

Geographic Range: This alliance is centered in the Edwards Plateau of Texas. It ranges into adjacent regions such as the Arbuckle Mountains of Oklahoma and the Stockton Plateau of Texas.

Nations: US

States/Provinces:  OK, TX




Confidence Level: Low

Confidence Level Comments: No Data Available

Grank: GNR

Greasons: No Data Available


Concept Lineage: No Data Available

Predecessors: No Data Available

Obsolete Names: No Data Available

Obsolete Parents: No Data Available

Synonomy: ? Juniperus ashei woodland alliance (Hoagland 1998a)
>< Ashe Juniper - Redberry (Pinchot) Juniper: 66 (Eyre 1980)
>< Pinyon - Juniper: 239 (Eyre 1980)
>< Pinyon Pine-Oak Series (Diamond 1993)

Concept Author(s): J. Teague, in Faber-Langendoen et al. (2013)

Author of Description: J. Teague

Acknowledgements: No Data Available

Version Date: 12-18-14

  • Amos, B. B., and F. R. Gehlbach. 1988. Edwards Plateau vegetation: Plant ecological studies in central Texas. Baylor University Press, Waco, TX. 144 pp.
  • Cogan, D. 2007c. Vegetation classification and mapping project report, Lyndon B. Johnson National Historical Park. Natural Resource Technical Report NPS/SOPN/NRTR--2007/073. National Park Service, Johnson City, TX. 118 pp.
  • Diamond, D. D. 1993. Classification of the plant communities of Texas (series level). Unpublished document. Texas Natural Heritage Program, Austin. 25 pp.
  • Diamond, D., G. Rowell, and D. Keddy-Hector. 1995. Conservation of Ashe juniper (Juniperus ashei Buchholz) woodlands of the Central Texas Hill Country. Natural Areas Journal 15:189-197.
  • Eyre, F. H., editor. 1980. Forest cover types of the United States and Canada. Society of American Foresters, Washington, DC. 148 pp.
  • 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.
  • 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.