Print Report
G899 Pinus monophylla - Juniperus osteosperma Woodland Group
Type Concept Sentence: This woodland group occurs on dry mountain ranges of the Great Basin region and eastern foothills of the Sierra Nevada and is characterized by an open to moderately dense tree canopy typically composed of a mix of Pinus monophylla and Juniperus osteosperma, but either tree species may dominate as long as there is significant presence of Pinus monophylla (not accidental) to characterize the stand as a pinyon-juniper stand and not the more xeric, typically lower-elevation Juniperus osteosperma woodland and savanna.
Common (Translated Scientific) Name: Singleleaf Pinyon - Utah Juniper Woodland Group
Colloquial Name: Great Basin Pinyon - Juniper Woodland
Hierarchy Level: Group
Type Concept: This woodland group occurs on dry mountain ranges of the Great Basin region and eastern foothills of the Sierra Nevada, and south in scattered locations throughout southern California. The vegetation is characterized by an open to moderately dense tree canopy typically composed of a mix of Pinus monophylla and Juniperus osteosperma, but either tree species may dominate as long as there is significant presence of Pinus monophylla (not accidental) to characterize the stand as a pinyon-juniper stand and not the more xeric, typically lower-elevation Juniperus osteosperma woodland and savanna. In some regions of southern California, Juniperus osteosperma is replaced by Juniperus californica. Cercocarpus ledifolius is a common associate and may occur in tree or shrub form. On the east slope of the Sierra Nevada in California, Pinus jeffreyi and Juniperus grandis may be minor components of higher elevation stands in these woodlands. The understory layers are variable, but shrubs such as Artemisia tridentata frequently form a moderately dense short-shrub layer. Other associated shrubs include Arctostaphylos patula, Artemisia arbuscula, Artemisia nova, Cercocarpus ledifolius, Cercocarpus intricatus, Coleogyne ramosissima, Juniperus californica, Quercus chrysolepis, Quercus gambelii, Quercus john-tuckeri, Quercus turbinella, and Yucca brevifolia. Bunchgrasses such as Bouteloua gracilis, Festuca idahoensis, Hesperostipa comata, Leymus cinereus, Poa fendleriana, Poa secunda, and Pseudoroegneria spicata are commonly present and may form an herbaceous layer. These woodlands are typically found at lower elevations, but range from 1500-2600 m. Stands occur on warm, dry sites on mountain slopes, mesas, plateaus and ridges. Severe climatic events occurring during the growing season, such as frosts and drought, are thought to limit the distribution of pinyon-juniper woodlands to relatively narrow altitudinal belts on mountainsides. These woodlands occur at lower elevation than ~Colorado Plateau Pinyon - Juniper Woodland Group (G900)$$ where sympatric.
Diagnostic Characteristics: These woodlands are characterized by diagnostic tree species Pinus monophylla that forms an open to dense tree layer often with the wider ranging Juniperus osteosperma or, less frequently, Juniperus californica in southern California. Juniperus osteosperma also may dominate woodland stands within the range of Pinus monophylla as long as there is significant presence of Pinus monophylla (not accidental) to characterize the stand as a pinyon-juniper stand and not the more xeric, typically lower-elevation Juniperus osteosperma woodland and savanna. Understory diagnostic species are characteristic of the Great Basin, such as Arctostaphylos patula, Artemisia nova, Artemisia tridentata, Cercocarpus intricatus, Cercocarpus ledifolius, Coleogyne ramosissima, Purshia stansburiana, Purshia tridentata, Pleuraphis jamesii, Pseudoroegneria spicata, Poa secunda, or Poa fendleriana.
Rationale for Nominal Species or Physiognomic Features: No Data Available
Classification Comments: This group corresponds to the Pinus monophylla-dominated portion of the persistent pinyon-juniper woodland type from Romme et al. (2009) that occurs on rocky uplands with shallow, coarse-textured, and often skeletal soils that support relatively sparse herbaceous cover and rarely burn.
Similar NVC Types: No Data Available
note: No Data Available
Physiognomy and Structure: This vegetation group is characterized by an open to moderately dense, short (2-10 m tall) evergreen needle-leaved or scale-leaved tree canopy. Open to dense shrub and herbaceous layers may be present or absent. Herbaceous layers are usually sparse.
Floristics: These woodlands are characterized by an open to moderately dense tree canopy typically composed of a mix of Pinus monophylla and Juniperus osteosperma, but either tree species may dominate as long as there is significant presence of Pinus monophylla (not accidental) to characterize the stand as a pinyon-juniper stand and not the more xeric, typically lower-elevation Juniperus osteosperma woodland and savanna. In some regions of southern California, Juniperus osteosperma is replaced by Juniperus californica. Cercocarpus ledifolius is a common associate and may occur in tree or shrub form. On the east slope of the Sierra Nevada in California, Pinus jeffreyi and Juniperus grandis (= Juniperus occidentalis var. australis) may be minor components of these woodlands. Understory layers are variable, but shrubs such as Artemisia tridentata frequently form a moderately dense short-shrub layer. Other associated shrubs include Amelanchier utahensis, Arctostaphylos patula, Arctostaphylos pungens, Artemisia arbuscula, Artemisia nova, Ceanothus greggii, Cercocarpus intricatus, Coleogyne ramosissima, Glossopetalon spinescens, Peraphyllum ramosissimum, Prunus virginiana, Purshia stansburiana, Purshia tridentata, Quercus chrysolepis, Quercus gambelii, Quercus john-tuckeri, Quercus turbinella, Shepherdia rotundifolia, and Yucca brevifolia. Bunchgrasses such as Bouteloua gracilis, Festuca idahoensis, Hesperostipa comata, Leymus cinereus (= Elymus cinereus), Poa fendleriana, Poa secunda, and Pseudoroegneria spicata are commonly present and may form an herbaceous layer.
Dynamics: Pinus monophylla, Juniperus osteosperma, and Juniperus scopulorum are slow-growing, long-lived trees (about 650 years for Juniperus osteosperma, 300 years for Juniperus scopulorum, and 800 years for Pinus monophylla although older individuals are known) (Burns and Honkala 1990a, Zlatnik 1999e, Zouhar 2001b, Scher 2002, Sawyer et al. 2009). These trees are killed by severe fire because of thin bark and lack of self-pruning; however, mature trees can survive low-intensity fires (Zouhar 2001b, Sawyer et al. 2009). Although there is variation in fire frequency because of the diversity of site characteristics, stand-replacing fire was uncommon in this ecological system historically, with an average fire-return interval (FRI) of 100-1000 years occurring primarily during extreme fire behavior conditions and during long droughts (Zouhar 2001b) (Landfire 2007a, BpS model 1210190). Mixed-severity fire (average FRI of 100-500 years) was characterized as a mosaic of replacement and surface fires distributed through stands in patches at a fine scale (<0.1 acre) (LF BpS model 1210190).
Environmental Description: This woodland group occurs on dry mountain ranges of the Great Basin region and eastern foothills of the Sierra Nevada, and south in scattered locations throughout southern California. It is typically found at lower elevations but ranges from 1500-2600 m. These woodlands occur on warm, dry sites on mountain slopes, mesas, plateaus and ridges. Substrates are variable but are often rocky with shallow soil. Severe climatic events occurring during the growing season, such as frosts and drought, are thought to limit the distribution of pinyon-juniper woodlands to relatively narrow altitudinal belts on mountainsides.
Geographic Range: This woodland group occurs on dry mountain ranges of the Great Basin region and eastern foothills of the Sierra Nevada. It extends southwest in California to the northern Transverse Ranges (Ventura County) and San Jacinto Mountains (Riverside County). Stands do not occur in Mexico.
Nations: US
States/Provinces: AZ, CA, CO, ID, MT, NM?, NV, UT, WY
Plot Analysis Summary:
http://vegbank.org/natureserve/ELEMENT_GLOBAL.2.1085055
Confidence Level: Moderate
Confidence Level Comments: No Data Available
Grank: GNR
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.c Singleleaf Pinyon - Utah Juniper Woodland Group | G899 | 1.B.2.Nc.1.c |
| Alliance | A2108 Singleleaf Pinyon - Utah Juniper Shrubby Woodland Alliance | A2108 | 1.B.2.Nc.1.c |
| Alliance | A2109 Singleleaf Pinyon - Utah Juniper Grassy Open Woodland Alliance | A2109 | 1.B.2.Nc.1.c |
| Alliance | A4370 Utah Juniper Great Basin Shrubby Woodland Alliance | A4370 | 1.B.2.Nc.1.c |
Concept Lineage: No Data Available
Predecessors: No Data Available
Obsolete Names: No Data Available
Obsolete Parents: No Data Available
Synonomy: = PIMO Series (West et al. 1998)
- Barbour, M. G., and J. Major, editors. 1977. Terrestrial vegetation of California. John Wiley and Sons, New York. 1002 pp.
- Brown, D. E., C. H. Lowe, and C. P. Pase. 1979. A digitized classification system for the biotic communities of North America with community (series) and association examples for the Southwest. Journal of the Arizona-Nevada Academy of Science 14:1-16.
- Brown, D. E., editor. 1982a. Biotic communities of the American Southwest-United States and Mexico. Desert Plants Special Issue 4(1-4):1-342.
- Burns, R. M., and B. H. Honkala, technical coordinators. 1990a. Silvics of North America: Volume 1. Conifers. Agriculture Handbook 654. USDA Forest Service, Washington, DC. 675 pp.
- 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, 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]
- Holland, V. L., and D. J. Keil. 1995. California vegetation. Kendall/Hunt Publishing Company, Dubuque, IA. 516 pp.
- Küchler, A. W. 1964. Potential natural vegetation of the conterminous United States. American Geographic Society Special Publication 36. New York, NY. 116 pp.
- LANDFIRE [Landfire National Vegetation Dynamics Database]. 2007a. Landfire National Vegetation Dynamics Models. Landfire Project, USDA Forest Service, U.S. Department of Interior. (January - last update) [http://www.LANDFIRE.gov/index.php] (accessed 8 February 2007).
- Romme, W. H., C. D. Allen, J. D. Balley, W. L. Baker, B. T. Bestelmeyer, P. M. Brown, K. S. Eisenhart, M. L. Floyd, D. W. Huffman, B. F. Jacobs, R. F. Miller, E. H. Muldavin, T. W. Swetnam, R. J. Tausch, and P. J. Weisberg. 2009. Historical and modern disturbance regimes, stand structures, and landscape dynamics in pinon-juniper vegetation of the western United States. Rangeland Ecology & Management 62:203-222.
- Sawyer, J. O., T. Keeler-Wolf, and J. Evens. 2009. A manual of California vegetation. Second edition. California Native Plant Society, Sacramento CA. 1300 pp.
- Scher, J. S. 2002. Juniperus scopulorum. In: Fire Effects Information System [Online]. USDA Forest Service, Rocky Mountain Research Station, Fire Sciences Laboratory (Producer). [http://www.fs.fed.us/database/feis/] (accessed 25 June 2015).
- Shiflet, T. N., editor. 1994. Rangeland cover types of the United States. Society for Range Management. Denver, CO. 152 pp.
- Thorne, R. F., A. A. Schoenherr, C. D. Clements, and J. A. Young. 2007. Transmontane coniferous vegetation. Pages 574-586 in: M. G. Barbour, T. Keeler-Wolf, and A. A. Schoenherr, editors. Terrestrial vegetation of California. Third edition. University of California Press, Berkeley.
- West, N. E. 1999a. Juniper-pinon savannas and woodlands of western North America. Pages 288-308 in: R. C. Anderson, editor. Savannas, barrens, and rock outcrop plant communities of North America. Cambridge University Press, New York.
- West, N. E., R. J. Tausch, and P. T. Tueller. 1998. A management-oriented classification of pinyon-juniper woodlands of the Great Basin. General Technical Report RMRS-GTR-12. USDA Forest Service, Rocky Mountain Research Station, Ogden, UT. 42 pp.
- Zlatnik, E. 1999e. Juniperus osteosperma. In: Fire Effects Information System [Online]. USDA Forest Service, Rocky Mountain Research Station, Fire Sciences Laboratory (Producer). [http://www.fs.fed.us/database/feis/] (accessed 25 June 2015).
- Zouhar, K. L. 2001b. Pinus monophylla. In: Fire Effects Information System [Online]. USDA Forest Service, Rocky Mountain Research Station, Fire Sciences Laboratory (Producer). [http://www.fs.fed.us/database/feis/] (accessed 2 January 2011).