Print Report
G228 Pinus ponderosa Southern Rocky Mountain Forest & Woodland Group
Type Concept Sentence: This widespread woodland group is found throughout the cordillera of the Rocky Mountains at lower treeline typically in warm, dry, exposed sites where the dominant tree is Pinus ponderosa (primarily var. scopulorum and var. brachyptera) usually with a shrubby layer of species of Artemisia, Arctostaphylos, Cercocarpus, Purshia, Symphoricarpos, and Quercus gambelii, with Pseudoroegneria spicata, Pascopyrum smithii, and species of Achnatherum, Bouteloua, Festuca, Hesperostipa, and Muhlenbergia common grasses.
Common (Translated Scientific) Name: Ponderosa Pine Southern Rocky Mountain Forest & Woodland Group
Colloquial Name: Southern Rocky Mountain Ponderosa Pine Forest & Woodland
Hierarchy Level: Group
Type Concept: This widespread group is most common throughout the cordillera of the Rocky Mountains, from the Greater Yellowstone region south. It is also found in the Colorado Plateau region, west into scattered locations of the Great Basin. Its easternmost extent in Wyoming is in the Bighorn Mountains. These woodlands occur at the lower treeline/ecotone between grassland or shrubland and more mesic coniferous forests typically in warm, dry, exposed sites. Elevations range from less than 1900 m in northern Wyoming to 2800 m in the New Mexico mountains. Occurrences are found on all slopes and aspects; however, moderately steep to very steep slopes or ridgetops are most common. This group generally occurs on soils derived from igneous, metamorphic, and sedimentary material, with characteristic features of good aeration and drainage, coarse textures, circumneutral to slightly acidic pH, an abundance of mineral material, rockiness, and periods of drought during the growing season. Pinus ponderosa (primarily var. scopulorum and var. brachyptera) is the predominant conifer; Pseudotsuga menziesii, Pinus edulis, Pinus contorta, Populus tremuloides, and Juniperus spp. may also be present in the tree canopy. The understory is usually shrubby, with Artemisia nova, Artemisia tridentata, Arctostaphylos patula, Arctostaphylos uva-ursi, Cercocarpus montanus, Purshia stansburiana, Purshia tridentata, Quercus gambelii, Symphoricarpos spp., Prunus virginiana, Amelanchier alnifolia, and Rosa spp. common. Pseudoroegneria spicata, Pascopyrum smithii, and species of Hesperostipa, Achnatherum, Festuca, Muhlenbergia, and Bouteloua are some of the common grasses. Mixed fire regimes and surface fires of variable return intervals maintain these woodlands, depending on climate, degree of soil development, and understory density.
Diagnostic Characteristics: Pinus ponderosa (primarily var. scopulorum and var. brachyptera) is the predominant conifer; Pseudotsuga menziesii, Pinus edulis, Pinus contorta, Populus tremuloides, and Juniperus spp. may also be present in the tree canopy. The understory is usually shrubby, with Artemisia nova, Artemisia tridentata, Arctostaphylos patula, Arctostaphylos uva-ursi, Cercocarpus montanus, Purshia stansburiana, Purshia tridentata, Quercus gambelii, Symphoricarpos spp., Prunus virginiana, Amelanchier alnifolia, and Rosa spp. common. Pseudoroegneria spicata, Pascopyrum smithii, and species of Hesperostipa, Achnatherum, Festuca, Muhlenbergia, and Bouteloua are some of the common grasses.
Rationale for Nominal Species or Physiognomic Features: No Data Available
Classification Comments: ~Central Rocky Mountain Ponderosa Pine Open Woodland Group (G213)$$ in the eastern Cascades, Okanogan and Northern Rockies regions receives winter and spring rains, and thus has a greater spring "green-up" than the drier woodlands in the Central Rockies. This group also intergrades with ~Southern Rocky Mountain Ponderosa Pine Open Woodland Group (G229)$$. They are distinguished by the high-frequency surface-fire regime, less steep or rocky environmental setting, and more open grassy understory structure of the savanna group. Ponderosa pine woodlands, savannas, and "escarpments''" of central and eastern Montana, eastern Wyoming, the Black Hills region, western Dakotas, and Nebraska are now included in ~Black Hills-Northwestern Great Plains Ponderosa Pine Forest & Woodland Group (G216)$$.
Similar NVC Types: No Data Available
note: No Data Available
Physiognomy and Structure: Conifer-dominated open forests or woodlands. Shrubs tend to predominate in the understory. Graminoids are common, but not as abundant as seen in the graminoid-dominated savanna group.
Floristics: This group is dominated by Pinus ponderosa with Pseudotsuga menziesii, Pinus edulis, Pinus contorta, Populus tremuloides, and Juniperus spp. as common canopy associates. In the southern Rocky Mountains and the mountains of southern Arizona and New Mexico, associated trees include Pseudotsuga menziesii, Abies concolor, Picea pungens, Pinus strobiformis, Pinus edulis, Pinus discolor, Pinus cembroides, Pinus flexilis, Juniperus scopulorum, and Populus tremuloides. In far southern stands, Juniperus deppeana may also be common. Average tree canopy cover ranges from 20-70%. The understory may include dense stands of shrubs or be dominated by grasses, sedges, or herbaceous species, although many of the associations are named for shrub species. Existing stands usually have younger cohorts of Pinus ponderosa present and may be less open than in the past. Understory shrub species include Artemisia nova, Artemisia tridentata, Arctostaphylos patula, Arctostaphylos uva-ursi, Cercocarpus montanus, Purshia stansburiana, Purshia tridentata, Quercus gambelii, Symphoricarpos spp., Fallugia paradoxa, Ribes spp., Robinia neomexicana, Alnus incana, Forestiera pubescens, Prunus virginiana, Amelanchier alnifolia, and Rosa spp. The herbaceous layer tends to vary inversely with shrub cover, but is composed primarily of graminoids. Important species include Bouteloua gracilis, Carex geyeri, Carex rossii, Carex pensylvanica, Koeleria macrantha, Leucopoa kingii (= Festuca kingii), Muhlenbergia straminea (= Muhlenbergia virescens), Muhlenbergia montana, Achnatherum hymenoides (= Oryzopsis hymenoides), Achnatherum occidentale (= Stipa occidentalis), Pseudoroegneria spicata, Poa secunda, Elymus elymoides, Festuca idahoensis, Festuca arizonica, and Hesperostipa comata (= Stipa comata). Important or diagnostic forb species include Aspidotis densa, Wyethia mollis, Balsamorhiza sagittata, Achillea millefolium, Sedum stenopetalum, Maianthemum racemosum (= Smilacina racemosa), Vicia americana, and species of many other genera, such as Erigeron, Lupinus, Fragaria, Lathyrus, Heterotheca, Arenaria, and Antennaria.
Dynamics: Pinus ponderosa is a drought-resistant, shade-intolerant conifer which usually occurs at lower treeline in the major ranges of the western United States. Historically, surface fires and drought were influential in maintaining open-canopy conditions in these woodlands. With settlement and subsequent fire suppression, occurrences have become denser. Presently, many occurrences contain understories of more shade-tolerant species, such as Pseudotsuga menziesii and/or Abies spp., as well as younger cohorts of Pinus ponderosa. These altered structures have affected fuel loads and fire regimes. Presettlement fire regimes were primarily frequent (5- to 15-year return intervals), low-intensity surface fires triggered by lightning strikes or deliberately set fires by Native Americans. With fire suppression and increased fuel loads, fire regimes are now less frequent and often become intense crownfires, which can kill mature Pinus ponderosa (Reid et al. 1999).
Establishment is erratic and believed to be linked to periods of adequate soil moisture and good seed crops, as well as fire frequencies, which allow seedlings to reach sapling size. Longer fire-return intervals have resulted in many occurrences having dense subcanopies of overstocked and unhealthy young Pinus ponderosa (Reid et al. 1999). Mehl (1992) states the following: "Where fire has been present, occurrences will be climax and contain groups of large, old trees with little understory vegetation or down woody material and few occurring dead trees. The age difference of the groups of trees would be large. Where fire is less frequent, there will also be smaller size trees in the understory giving the occurrence some structure with various canopy layers. Dead, down material will be present in varying amounts along with some occurring dead trees. In both cases the large old trees will have irregular open, large branched crowns. The bark will be lighter in color, almost yellow, thick and some will like have basal fire scars."
Grace''s warbler, pygmy nuthatch, and flammulated owl are indicators of a healthy ponderosa pine woodland. All of these birds prefer mature trees in an open woodland setting (Winn 1998, Jones 1998d, Levad 1998 as cited in Rondeau 2001).
Establishment is erratic and believed to be linked to periods of adequate soil moisture and good seed crops, as well as fire frequencies, which allow seedlings to reach sapling size. Longer fire-return intervals have resulted in many occurrences having dense subcanopies of overstocked and unhealthy young Pinus ponderosa (Reid et al. 1999). Mehl (1992) states the following: "Where fire has been present, occurrences will be climax and contain groups of large, old trees with little understory vegetation or down woody material and few occurring dead trees. The age difference of the groups of trees would be large. Where fire is less frequent, there will also be smaller size trees in the understory giving the occurrence some structure with various canopy layers. Dead, down material will be present in varying amounts along with some occurring dead trees. In both cases the large old trees will have irregular open, large branched crowns. The bark will be lighter in color, almost yellow, thick and some will like have basal fire scars."
Grace''s warbler, pygmy nuthatch, and flammulated owl are indicators of a healthy ponderosa pine woodland. All of these birds prefer mature trees in an open woodland setting (Winn 1998, Jones 1998d, Levad 1998 as cited in Rondeau 2001).
Environmental Description: This group within the region occurs at the lower treeline/ecotone between grassland or shrubland and more mesic coniferous forests typically in warm, dry, exposed sites at elevations ranging from 1980-2800 m (6500-9200 feet). It can occur on all slopes and aspects; however, it commonly occurs on moderately steep to very steep slopes or ridgetops. At higher elevations, it will typically occur on south- or west-facing slopes. This group generally occurs on soils derived from igneous, metamorphic, and sedimentary material, including basalt, basaltic, andesitic flows, intrusive granitoids and porphyrites, and tuffs (Youngblood and Mauk 1985). Characteristic soil features include good aeration and drainage, coarse textures, circumneutral to slightly acidic pH, an abundance of mineral material, and periods of drought during the growing season. Some occurrences may occur as edaphic climax communities on very skeletal, infertile, and/or excessively drained soils, such as pumice, cinder or lava fields, and scree slopes. Surface textures are highly variable in this group, ranging from sand to loam and silt loam. Exposed rock and bare soil consistently occur to some degree in all the associations. Pinus ponderosa / Arctostaphylos patula represents the extreme, with typically a high percentage of rock and bare soil present.
Precipitation generally contributes 25-60 cm annually to this group, mostly through winter storms and some monsoonal summer rains. Typically a seasonal drought period occurs throughout this group as well. Fire plays an important role in maintaining the characteristics of these open-canopy woodlands. However, soil infertility and drought may contribute significantly in some areas as well.
Climate: The quantity and timing of precipitation vary across the range of the group, ranging from 25-60 cm annually, with at least some seasonal drought. East of the Continental Divide and in the Southwest, summer precipitation predominates, whereas western stands receive most of their precipitation from westerly winter storms. Monsoonal summer rains can contribute a substantial proportion to the annual precipitation totals in the Southwest. Elevations decrease with increasing latitude, from less than 1000 m in eastern Washington to over 2750 m in southern Arizona and New Mexico. Soil/substrate/hydrology: Fire is a key factor in maintaining the open canopies characteristic of these woodlands, but soil drought or infertility may be equally important in some areas. This group generally occurs on soils derived from igneous, metamorphic, and sedimentary material, including basalt, basaltic, andesitic flows, intrusive granitoids and porphyrites, and tuffs (Youngblood and Mauk 1985). Characteristic soil features include good aeration and drainage, coarse textures, circumneutral to slightly acidic pH, an abundance of mineral material, and periods of drought during the growing season. Some occurrences may occur as edaphic climax communities on very skeletal, infertile, and/or excessively drained soils, such as pumice, cinder or lava fields, and scree slopes. Surface textures are highly variable in this group, ranging from sand to loam and silt loam. Exposed rock and bare soil consistently occur to some degree in all the associations.
Precipitation generally contributes 25-60 cm annually to this group, mostly through winter storms and some monsoonal summer rains. Typically a seasonal drought period occurs throughout this group as well. Fire plays an important role in maintaining the characteristics of these open-canopy woodlands. However, soil infertility and drought may contribute significantly in some areas as well.
Climate: The quantity and timing of precipitation vary across the range of the group, ranging from 25-60 cm annually, with at least some seasonal drought. East of the Continental Divide and in the Southwest, summer precipitation predominates, whereas western stands receive most of their precipitation from westerly winter storms. Monsoonal summer rains can contribute a substantial proportion to the annual precipitation totals in the Southwest. Elevations decrease with increasing latitude, from less than 1000 m in eastern Washington to over 2750 m in southern Arizona and New Mexico. Soil/substrate/hydrology: Fire is a key factor in maintaining the open canopies characteristic of these woodlands, but soil drought or infertility may be equally important in some areas. This group generally occurs on soils derived from igneous, metamorphic, and sedimentary material, including basalt, basaltic, andesitic flows, intrusive granitoids and porphyrites, and tuffs (Youngblood and Mauk 1985). Characteristic soil features include good aeration and drainage, coarse textures, circumneutral to slightly acidic pH, an abundance of mineral material, and periods of drought during the growing season. Some occurrences may occur as edaphic climax communities on very skeletal, infertile, and/or excessively drained soils, such as pumice, cinder or lava fields, and scree slopes. Surface textures are highly variable in this group, ranging from sand to loam and silt loam. Exposed rock and bare soil consistently occur to some degree in all the associations.
Geographic Range: This group is found throughout much of the Rocky Mountains cordillera, from northwestern Wyoming, south through the Rocky Mountains of Colorado and into New Mexico, and a few scattered stands in west Texas. In Arizona, it occurs on the Mogollon Rim north into the Colorado Plateau region and west into scattered locations of the Great Basin.
Nations: MX,US
States/Provinces: AZ, CO, ID?, MT, MXCHH, MXCOA, ND, NE, NM, NV, SD, TX, UT, WY
Plot Analysis Summary:
http://vegbank.org/natureserve/ELEMENT_GLOBAL.2.835821
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.Nb Rocky Mountain Forest & Woodland Division | D194 | 1.B.2.Nb |
| Macrogroup | 1.B.2.Nb.1 White Fir - Douglas-fir - Blue Spruce Forest Macrogroup | M022 | 1.B.2.Nb.1 |
| Group | 1.B.2.Nb.1.b Ponderosa Pine Southern Rocky Mountain Forest & Woodland Group | G228 | 1.B.2.Nb.1.b |
| Alliance | A3398 Ponderosa Pine Southern Rocky Mountain Forest & Woodland Alliance | A3398 | 1.B.2.Nb.1.b |
Concept Lineage: No Data Available
Predecessors: No Data Available
Obsolete Names: No Data Available
Obsolete Parents: No Data Available
Synonomy: < Interior Ponderosa Pine: 237 (Eyre 1980)
> Pine Series, Pinus ponderosa-Quercus gambelii Association - 122.321 (Brown et al. 1979)
> Pine Series, Pinus ponderosa Association - 122.321 (Brown et al. 1979)
> Pine Series, Pinus ponderosa-Mixed Conifer Association - 122.321 (Brown et al. 1979)
= Ponderosa Pine Series (Mauk and Henderson 1984)
= Ponderosa Pine Series (Muldavin et al. 1996)
= Ponderosa Pine Series (Youngblood and Mauk 1985)
= Ponderosa Pine Series (Komarkova et al. 1988b)
= Ponderosa Pine Series (Hoffman and Alexander 1976)
= Ponderosa Pine Series (DeVelice et al. 1986)
= Ponderosa Pine Series (Hess and Alexander 1986)
= Xeric Pinus ponderosa Forest (Peet 1981)
> Pine Series, Pinus ponderosa-Quercus gambelii Association - 122.321 (Brown et al. 1979)
> Pine Series, Pinus ponderosa Association - 122.321 (Brown et al. 1979)
> Pine Series, Pinus ponderosa-Mixed Conifer Association - 122.321 (Brown et al. 1979)
= Ponderosa Pine Series (Mauk and Henderson 1984)
= Ponderosa Pine Series (Muldavin et al. 1996)
= Ponderosa Pine Series (Youngblood and Mauk 1985)
= Ponderosa Pine Series (Komarkova et al. 1988b)
= Ponderosa Pine Series (Hoffman and Alexander 1976)
= Ponderosa Pine Series (DeVelice et al. 1986)
= Ponderosa Pine Series (Hess and Alexander 1986)
= Xeric Pinus ponderosa Forest (Peet 1981)
- 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.
- DeVelice, R. L., J. A. Ludwig, W. H. Moir, and F. Ronco, Jr. 1986. A classification of forest habitat types of northern New Mexico and southern Colorado. General Technical Report RM-131. USDA Forest Service, Rocky Mountain Forest and Range Experiment Station, Fort Collins, CO. 59 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]
- Hess, K., and R. R. Alexander. 1986. Forest vegetation of the Arapaho and Roosevelt national forests in northcentral Colorado: A habitat type classification. Research Paper RM-266. USDA Forest Service, Rocky Mountain Forest and Range Experiment Station, Fort Collins, CO. 48 pp.
- Hoffman, G. R., and R. R. Alexander. 1976. Forest vegetation of the Bighorn Mountains, Wyoming: A habitat type classification. Research Paper RM-170. USDA Forest Service, Rocky Mountain Forest and Range Experiment Station, Fort Collins, CO. 38 pp.
- Johansen, A. D., and R. G. Latta. 2003. Mitochondrial haplotype distribution, seed dispersal and patterns of post glacial expansion of ponderosa pine. Molecular Ecology 12:293-298.
- Jones, S. L. 1998d. Pygmy nuthatch. Pages 360-361 in: H. E. Kingery, editor. Colorado breeding bird atlas. Colorado Bird Atlas Partnership and Colorado Division of Wildlife, Denver.
- Komarkova, V. K., R. R. Alexander, and B. C. Johnston. 1988b. Forest vegetation of the Gunnison and parts of the Uncompahgre national forests: A preliminary habitat type classification. Research Paper RM-163. USDA Forest Service, Rocky Mountain Forest and Range Experiment Station, Fort Collins, CO. 65 pp.
- Mauk, R. L., and J. A. Henderson. 1984. Coniferous forest habitat types of northern Utah. General Technical Report INT-170. USDA Forest Service, Intermountain Forest and Range Experiment Station, Ogden, UT. 89 pp.
- Mehl, M. S. 1992. Old-growth descriptions for the major forest cover types in the Rocky Mountain Region. Pages 106-120 in: M. R. Kaufmann, W. H. Moir, and R. L. Bassett. Old-growth forests in the southwest and Rocky Mountain regions. Proceedings of the old-growth forests in the Rocky Mountains and Southwest conference, Portal, AZ. March 9-13, 1992. General Technical Report RM-213. USDA Forest Service, Rocky Mountain Forest and Range Experiment Station, Fort Collins, CO.
- Muldavin, E. H., R. L. DeVelice, and F. Ronco, Jr. 1996. A classification of forest habitat types of southern Arizona and portions of the Colorado Plateau. General Technical Report RM-GTR-287. USDA Forest Service, Rocky Mountain Forest and Range Experiment Station, Fort Collins, CO. 130 pp.
- Muldavin, E., R. DeVelice, and W. Dick-Peddie. 1987. Forest habitat types of the Prescott, Tonto and western Coronado national forests, Arizona. Unpublished final report prepared for Rocky Mountain Forest and Range Experiment Station, CO. 71 pp.
- Peet, R. K. 1978a. Latitudinal variation in southern Rocky Mountain forests. Journal of Biogeography 5:275-289.
- Peet, R. K. 1981. Forest vegetation of the Colorado Front Range. Vegetatio 45:3-75.
- Peet, R. K. 2000. Forests and meadows of the Rocky Mountains. Chapter 3 in: M. G. Barbour and W. D. Billings, editors. North American terrestrial vegetation. Second edition. Cambridge University Press, New York. 434 pp.
- Reid, M. S., K. A. Schulz, P. J. Comer, M. H. Schindel, D. R. Culver, D. A. Sarr, and M. C. Damm. 1999. An alliance level classification of vegetation of the coterminous western United States. Unpublished final report to the University of Idaho Cooperative Fish and Wildlife Research Unit and National Gap Analysis Program, in fulfillment of Cooperative Agreement 1434-HQ-97-AG-01779. The Nature Conservancy, Western Conservation Science Department, Boulder, CO.
- Rondeau, R. 2001. Ecological system viability specifications for Southern Rocky Mountain ecoregion. First edition. Colorado Natural Heritage Program, Colorado State University, Fort Collins, CO. 181 pp.
- Winn, R. 1998. Flammulated owl. Pages 210-211 in: H. E. Kingery, editor. Colorado breeding bird atlas. Colorado Bird Atlas Partnership and Colorado Division of Wildlife, Denver.
- Youngblood, A. P., and R. L. Mauk. 1985. Coniferous forest habitat types of central and southern Utah. General Technical Report INT-187. USDA Forest Service, Intermountain Research Station, Ogden, UT. 89 pp.