Print Report

CEGL000787 Pinus edulis - Juniperus spp. / Poa fendleriana Woodland

Type Concept Sentence: No Data Available

Common (Translated Scientific) Name: Two-needle Pinyon - Juniper species / Muttongrass Woodland

Colloquial Name: No Data Available

Hierarchy Level:  Association

Type Concept: This association is widespread and common throughout the Colorado Plateau of Utah, Arizona, New Mexico and Colorado. This woodland association is characterized by an open to moderately closed, mixed canopy of Pinus edulis and Juniperus osteosperma, about 2-10 m tall. The understory is dominated by the bunchgrass Poa fendleriana with up to 25% cover. Scattered shrubs present are varied and fail to form a stratum. Stands occur on the slopes of canyons, ridges, toeslopes, alluvial fans, benches and plateaus at elevations ranging from 1525 to 2560 m (5000-8400 feet). Slopes range from 4-50% and are oriented to any aspect. Soils are sandy, sandy loam, silt loam or clay loam.

Diagnostic Characteristics: This woodland often has an overstory of tall Pinus edulis and Juniperus spp., with a grassy understory. Poa fendleriana is common, but Festuca arizonica is absent.

Rationale for Nominal Species or Physiognomic Features: No Data Available

Classification Comments: This association is largely known and described from National Park Service inventory efforts in the Colorado Plateau. Even if stands have relatively sparse cover of Poa fendleriana (<5%), if no other species are present with more than trace cover, they have been placed in this association rather than ~Pinus edulis - Juniperus osteosperma / Sparse Understory Woodland (CEGL002148)$$.

Similar NVC Types: No Data Available
note: No Data Available
Physiognomy and Structure: No Data Available

Floristics: This woodland association is widespread and relatively common at moderate elevations throughout the Colorado Plateau. Total vegetation cover ranges from 40% to more than 75%. This woodland association is characterized by an open to moderately closed, mixed canopy of Pinus edulis and Juniperus osteosperma 2-10 m tall. In the southern part of the range, Juniperus monosperma and Juniperus scopulorum may be present in the canopy. The understory is dominated by the bunchgrass Poa fendleriana with between 1 and 25% cover. Scattered shrubs present include Amelanchier utahensis, Artemisia nova, Artemisia tridentata, Cercocarpus montanus, Gutierrezia sarothrae, Quercus gambelii, Purshia tridentata, Yucca baccata, Opuntia spp., Symphoricarpos oreophilus, Fallugia paradoxa, and Fendlera rupicola. Other common herbaceous species (always with less cover than Poa fendleriana) include Achnatherum hymenoides, Bouteloua gracilis, Hesperostipa comata, Heterotheca villosa, Koeleria macrantha, Muhlenbergia montana, Blepharoneuron tricholepis, Pascopyrum smithii, Bouteloua gracilis, Balsamorhiza sagittata, Mirabilis multiflora, Penstemon linarioides, and Petradoria pumila.

Dynamics:  Stands with grassy understories tend to occur in areas with deeper, finer-textured soils that are some distance from the rim of Mesa Verde (Erdman et al. 1969). Most sampled stands appear to be in mature to old-growth condition. This association is vulnerable to fire; most of the stands at Mesa Verde National Park have been converted by fire in the past 30 years to weedy herbaceous communities (Erdman 1969, Floyd et al. 2001).
Environmental Description:  This association is widespread and common throughout the Colorado Plateau of Utah, Arizona, New Mexico and Colorado. It occurs on the gentle to moderate slopes of canyons, ridges, toeslopes, benches and plateaus at elevations ranging from 1525 to 2560 m (5000-8400 feet). Stands may occur on slopes ranging from 4 to 50% and oriented to any aspect. Soils are sandy, sandy loam, silt loam or clay loam derived from sedimentary, granitic or metamorphic rocks, Straight Cliffs Formation and/or from talus/colluvium. A third to half the unvegetated ground surface is bare ground, and in some plots large rocks and gravel cover up to a third of the surface. In some cases, cryptogamic crusts and moss or litter cover up to 25% of the soil surface.
Geographic Range: This association occurs at moderate elevations in the Colorado Plateau region of western Colorado, northern Arizona and New Mexico and eastern Utah.

Nations: US

States/Provinces:  AZ, CO, NM, UT


Confidence Level: High

Confidence Level Comments: No Data Available
Grank: G5

Greasons: No Data Available
Type Name Database Code Classification Code
Class 1 Forest & Woodland Class C01 1
Subclass 1.B Temperate & Boreal Forest & Woodland Subclass S15 1.B
Formation 1.B.2 Cool Temperate Forest & Woodland Formation F008 1.B.2
Division 1.B.2.Nc Western North American Pinyon - Juniper Woodland & Scrub Division D010 1.B.2.Nc
Macrogroup 1.B.2.Nc.1 Singleleaf Pinyon - Utah Juniper - Western Juniper Intermountain Woodland Macrogroup M896 1.B.2.Nc.1
Group 1.B.2.Nc.1.a Two-needle Pinyon - Utah Juniper Woodland Group G900 1.B.2.Nc.1.a
Alliance A3572 Two-needle Pinyon - Utah Juniper Grassy Open Woodland Alliance A3572 1.B.2.Nc.1.a
Association CEGL000787 Two-needle Pinyon - Juniper species / Muttongrass Woodland CEGL000787 1.B.2.Nc.1.a
Concept Lineage: No Data Available

Predecessors: No Data Available

Obsolete Names: No Data Available

Obsolete Parents: No Data Available
Synonomy: = Pinus edulis - Juniperus osteosperma / Poa fendleriana Plant Association (Johnston 1987)
= Pinus edulis / Poa fendleriana (Stuever and Hayden 1997b)
= Pinus edulis / Poa fendleriana Plant Association (Larson and Moir 1987)
Concept Author(s): M.C. Stuever and J.S. Hayden (1997b)

Author of Description: J. Coles and G. Kittel

Acknowledgements: No Data Available

Version Date: 10-16-18
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