Foothills Limber Pine - Juniper Woodland
Global Name:
Rocky Mountain Foothill-Rock Outcrop Limber Pine - Juniper Woodland
Global Rank:
G4G5
State Rank:
S4
(see reason below)
External Links
State Rank Reason
This low elevation forest and woodland type is widespread east of the Continental Divide and likely has increased in extent in some areas. Threats from blister rust on limber pine and increases in the frequency of severe wildfires will likely impact some of the habitat.
General Description
This National Vegetation Classification Group occurs in the foothills and lower montane zones in the Rocky Mountain and Intermountain Regions in the southern half of Montana, and on escarpments extending out onto the western Great Plains. It occurs primarily east of the Continental Divide though some communities dominated by Rocky Mtn Juniper also occur west of the Divide. Vegetation is characterized by an open-tree canopy or patchy woodland that is dominated by Limber Pine (Pinus flexilis) and/or Rocky Mountain Juniper (Juniperus scopulorum). In the Pryor Mountains, Utah Juniper (Juniperus osteosperma) reaches its northern extent and may be present or co-dominate on some sites, though stands dominated solely by Utah Juniper are part of the Utah Juniper Woodland Group. Douglas-fir (Pseudotsuga menziesii) and Ponderosa Pine (Pinus ponderosa) may be present at some sites. Elevations of sites range from 4,000ft to as high as approximately 6,500ft in southwest Montana. At lower elevations, it can occur on all aspects and on relatively level terrain. Stands of Limber Pine at higher elevations, lacking Rocky Mtn Juniper and with a mostly different component of undergrowth species are included in the Montane - Subalpine Limber Pine Woodlands. In Montana, limber pine stands are found mainly on calcareous substrates. Soils generally have a high rock component (generally over 50% cover) and are coarse- to fine-textured, often gravelly.
This group incorporates the lower and drier plant associations included within the Rocky Mountain Foothill Limber Pine - Juniper Woodland Ecological System
Diagnostic Characteristics
Xeric Conifer Forest and Woodlands; Foothills and Lower Montane Zones, Great Plains Rocky Mtn and Intermountain Region; Low to Moderate Canopy Cover; Calcareous Soils; Gravel, Rock and Bare Soil Common; Soils with an A-Horizon <10cm.
Typical Dominants: Limber Pine (Pinus flexilis), Rocky Mtn Juniper (Juniperus scopulorum), Utah Juniper (Juniperus osteosperma)
Similar Systems
Range
This group occurs in the foothills and lower montane zones east of the Continental Divide and onto the plains. It is common along the lower elevations of several of the Island Ranges and on escarpments extending out into the western Great Plains. It is common in and near the Pryor Mountains in south-central Montana. This group also occurs in scattered locations west of the Divide and is represented by communities dominated by Rocky Mtn Juniper.
In Montana, G209 occurs in Level III Ecoregions: 17 (Middle Rockies), 18 (Wyoming Basin), 41 (Canadian Rockies), 42 (Northwestern Glaciated Plains), and 43 (Northwestern Great Plains).
In Montana, G209 occurs within these Major Land Resource Areas: 32 - Northern Intermountain Desertic Basins, 43B-Central Rocky Mountains, 46 - Northern and Central Rocky Mountain Foothills; 52 – Brown Glaciated Plains, 58A - Northern Rolling High Plains, Northern Part.
Density and Distribution
Based on 2025 land cover layer. Grid on map is based on USGS 7.5 minute quadrangle map boundaries.
Mapped Distribution by County
Beaverhead, Big Horn, Blaine, Broadwater, Carbon, Cascade, Chouteau, Deer Lodge, Fergus, Flathead, Gallatin, Glacier, Golden Valley, Granite, Hill, Jefferson, Judith Basin, Lewis and Clark, Liberty, Madison, Meagher, Missoula, Musselshell, Park, Petroleum, Phillips, Pondera, Powell, Ravalli, Silver Bow, Stillwater, Sweet Grass, Teton, Toole, Wheatland, Yellowstone
Based on 2025 land cover layer.
Spatial Pattern
Large Patch
Environment
Communities in G209 are found on sites with elevations from 4,000ft to as high as approximately 6,500ft in southwest Montana. At lower elevations, it can occur on all aspects and on relatively level terrain. In Montana, limber pine stands are found mainly on calcareous substrates. Rocky Mountain juniper stands are often found in complex transitional zones or growing on exposed or severe sites within other forest groups. These juniper stands can exhibit a savanna-like character in southwestern Montana. Soils generally have a high rock component (generally over 50% cover) and are coarse- to fine-textured, often gravelly. They are generally poorly developed, shallow, have low moisture holding capacity and are easily erodible, so in some occurrences, little topsoil is present. Although this group can be seen on gently rolling terrain, limestone cliffs, and exposed bluffs, it is most often found on rocky ridges and steep rocky slopes, and can survive in extremely windswept areas at the lower treeline. Climate is characterized by a relatively small amount of precipitation, with the wettest months during the growing season, very low humidity, and wide annual and diurnal temperature ranges.
Vegetation
Vegetation is characterized by an open-tree canopy or patchy woodland that is dominated by Limber Pine (Pinus flexilis) and/or Rocky Mountain Juniper (Juniperus scopulorum). In the Pryor Mountains, Utah Juniper (Juniperus osteosperma) reaches its northern extent and may be present or co-dominate on some sites. Douglas-fir (Pseudotsuga menziesii) and Ponderosa Pine (Pinus ponderosa) may be present at some sites. A sparse to moderately dense short-shrub layer is usually present. In southern Montana, Big Sagebrush (Artemisia tridentata), Black sagebrush (Artemisia nova), Curl-leaf Mountain Mahogany (Cercocarpus ledifolius), Broom Snakeweed (Gutierrezia sarothrae) and Plains Pricklypear (Opuntia polyacantha) are commonly present. The herbaceous layer is generally sparse and typically dominated by perennial graminoids such as Sandberg’s bluegrass (Poa secunda), Bluebunch Wheatgrass (Elymus spicatus), Prairie Junegrass (Koeleria macrantha), Purple Threeawn (Arista purpurea), Blue Grama (Bouteloua gracilis), Spike Fescue (Leucopoa kingii), Indian ricegrass (Oryzopsis hymenoides), and Threadleaf Sedge (Carex filifolia). Forb diversity can be very high. Some common forbs include Arenaria hookeri, Astragalus spp, Cryptantha spp, Erigeron spp, Eriogonum ovalifolium, Gaura coccinea, Locoweeds (Oxytropis spp). Phlox spp, Petrophytum caespitosum, Penstemon spp, Senecio canus, Stenotus spp, and Tetraneuris acaulis. Bryophyte and lichen cover are usually sparse (DeVelice and Lesica 1993, Pfister et al, 1977).
In Montana, 9 Associations grouped into 3 Alliances are currently recognized. These are relatively well-described and likely represent the overall diversity of the group within Montana.
National Vegetation Classification
Download the complete NVC hierarchy for Montana
TT2 B02 Temperate-Boreal Forest and Woodland
TT2.b S92 Cool Temperate Forest and Woodland
TT2.b3 F112 Temperate Continental Conifer Forest and Woodland
TT2.b3.Nb D337 Rocky Mountain Foothills and Montane Forest and Woodland
TT2.b3.Nb.3 M501 Central Rocky Mountain Montane Forest and Woodland
TT2.b3.Nb.3.f G209 Rocky Mountain Foothill-Rock Outcrop Limber Pine - Juniper Woodland
A3424 Pinus flexilis / Cercocarpus montanus Woodland Alliance
CEGL000808 Pinus flexilis / Juniperus osteosperma Woodland
CEGL000809 Pinus flexilis / Juniperus scopulorum Woodland
CEGL000813 Pinus flexilis / Pseudoroegneria spicata Woodland
A3426 Juniperus scopulorum - Juniperus osteosperma / Artemisia tridentata Shrubby Woodland Alliance
CEGL000734 Juniperus osteosperma / Cercocarpus ledifolius Woodland
CEGL000742 Juniperus scopulorum / Artemisia nova Woodland
CEGL000743 Juniperus scopulorum / Artemisia tridentata Woodland
CEGL000744 Juniperus scopulorum - Cercocarpus ledifolius Woodland
CEGL000745 Juniperus scopulorum / Cercocarpus montanus Woodland
A3427 Juniperus scopulorum - Juniperus osteosperma / Pseudoroegneria spicata Woodland Alliance
CEGL000748 Juniperus scopulorum / Pseudoroegneria spicata Woodland
*Disclaimer: Some Alliances and Associations are considered provisional. Some require further documentation to verify their occurrence in the state
and some may be modified or deleted in future revisions after collection of additional data and information.
Dynamic Processes
Major disturbances in this group include fire, soil erosion from over-used range, and biotic vectors. Fire is infrequent and spotty as the semi-arid environment and rocky substrates inhibit growth of a continuous canopy and the fine fuels that are needed for continuous fire spread. However, some of these woodlands often originate with and are likely maintained by fire. Regeneration on burns within Limber Pine stands is largely from germination of seedlings from Clark's nutcracker seed caches. Clark's nutcrackers are the primary harvester and disperser of its seeds. Fire can easily kill young Limber Pine and Rocky Mountain Juniper because of their thin bark (Fischer and Clayton, 1983), however, fuel loads in this group are generally light due to open rocky terrain, and fires do not generate severe damage or considerably alter vegetation composition. In comparison with upper treeline Limber Pine communities, foothill populations are thought to experience greater disturbance frequency (Schuster et al., 1995), and fire return intervals vary between 50 and 400 years (U.S. Department of Agriculture, 2012). Over time Limber Pine woodlands have shifted both up- and down-slope in response to changing climate and drought, and are considered to be particularly sensitive to future change (Means 2010).
Limber Pine occurs on dry, rocky sites that are typified by extreme winter weather and droughty summer conditions that offer marginal conditions for tree growth. Consequently, mortality from abiotic and biotic stressors is high in some areas. Limber pine is highly susceptible to white pine blister rust (Cronartium ribicola), the pine needle pathogen (Dothistroma septospora), and mountain pine beetles (Dendroctonus ponderosae). It can also be heavily infected or killed by limber pine dwarf-mistletoe (Arceuthobium cyanocarpum), particularly in south-central and southwestern Montana (Jackson et al., 2010), and is susceptible to infestation by cone beetles (Conophthorus contortae), the ponderosa pine cone worm (Dioryctria auranticella), and the western conifer seed bug (Leptoglossus occidentalis). Resistance to blister rust and mountain pine beetle is lower for Limber Pine than for other North American pines affected by these biotic agents (Hoff and McDonald 1993; Means 2010), and drought can exacerbate vulnerability to pine beetle attack (Jackson et al., 2010). The most significant damage due to biotic factors appears to occur at locations on the Lewis and Clark National Forest along the northern Rocky Mountain Front, the Gravelly range and sections of the Yellowstone ecosystem in southwestern Montana. Large numbers of trees have very thin crowns and poor terminal growth, and severe mortality is occurring in some areas.
Under natural conditions, Rocky Mountain Juniper seedlings become established on moist sites in partial shade (Burns and Honkala 1990). Stands found in southwestern Montana may exhibit a savanna-like character due to the inability of Rocky Mountain Juniper to establish on drier micro-sites. Rocky Mountain Juniper is generally shallow rooted, and forest health can be negatively affected by heavy grazing, especially on exposed sites with erodible soils. Although Rocky Mountain juniper is relatively resistant to disease and tolerant of insects, several insect pests do attack this species including cedar flathead borers (Chrysobothris spp.) and bark beetles (Phloeosinus spp.) (Scher, 2002). Additionally, mistletoes (Phoradendron spp.), a blight caused by Cercospora sequoia, and cedar apple rust (Gymnosporangium juniper virgiananae) can be especially problematic (Burns and Honkala 1990).
Management
In the absence of natural fire, periodic low to moderate intensity prescribed burns can be implemented during late fall months to maintain and enhance Limber Pine regeneration, although results may be variable due to insufficient ground fuels and rocky terrain typical of these communities. Fire may kill younger Limber Pine and Rocky Mountain Juniper because of their thin bark. Thinning may also be used in particularly dense stands to reduce spread of mountain pine beetles (Bureau of Land Management, 2011). In light of blister rust prevalence, stands can be managed to maintain Limber Pine forest composition, and to diversify age structure to include regeneration, thereby encouraging natural selection of rust resistant individuals (Jackson et al., 2010). On sites with slopes and forage that support domestic livestock, use can be monitored to maintain soil integrity. Prolonged drought and white pine blister rust (Cronartium rubicola) have decimated limber pine along the Rocky Mountain Front (and elsewhere), resulting in a skeleton woodland with scattered Douglas-firs as the only living trees.
Restoration Considerations
Reintroduction of prescribed fire fosters Limber Pine regeneration because it provides open sites and exposed mineral soils that are suitable for Clark's nutcracker to cache seeds, and for seedlings to establish. Augmenting natural Limber Pine regeneration with seed sources that exhibit some resistance to blister rust or, in some cases, with nursery stock, will be necessary in areas where seed sources are absent or greatly reduced. Blister rust-resistant or tolerant trees can be identified in previously infected stands, or by screening for an identified resistance gene (Schoettle and Sniezko 2007; Schoettle et al. 2014). Direct seeding may be the most practical restoration method on most sites, however seed-transfer guidelines should be considered when the seed source is a considerable distance from the seeding site (Schoettle and Sniezko 2007). Germination will take place during the first growing season after fall caching or direct seeding.
Because this group is characterized by shallow soils, outplanting of nursery stock may be limited to microsites with deeper soil pockets. Out-planted seedling survival has been shown to be higher when seedlings are planted on microsites with some cover, when seedlings are planted in clumps rather than singly, and when competition from surrounding vegetation is minimized (Asebrook et al. 2011). Seedling health was marginally improved in burned areas compared to unburned areas within an experimental area in Waterton Lakes National Park, Alberta (Asebrook et al. 2006).
Species Associated with this Community
- How Lists Were Created and Suggested Uses and Limitations
Animal Species Associations
Please note that while all vertebrate species have been systematically associated with vegetation communities, only a handful of invertebrate species have been associated with vegetation communities and invertebrates lists for each vegetation community should be regarded as incomplete. Animal species associations with natural vegetation communities that they regularly breed or overwinter in or migrate through were made by:
- Using personal observations and reviewing literature that summarize the breeding, overwintering, or migratory habitat requirements of each species (Dobkin 1992, Hart et al. 1998, Hutto and Young 1999, Maxell 2000, Werner et al. 2004, Adams 2003, and Foresman 2012);
- Evaluating structural characteristics and distribution of each vegetation community relative to the species' range and habitat requirements;
- Examining the observation records for each species in the state-wide point observation database associated with each vegetation community;
- Calculating the percentage of observations associated with each vegetation community relative to the percent of Montana covered by each vegetation community to get a measure of "observations versus availability of habitat".
Species that breed in Montana were only evaluated for breeding habitat use. Species that only overwinter in Montana were only evaluated for overwintering habitat use. Species that only migrate through Montana were only evaluated for migratory habitat use. In general, species are listed as associated with a vegetation community if it contains structural characteristics known to be used by the species. However, species are not listed as associated with a vegetation community if we found no support in the literature for the species’ use of structural characteristics of the community even if point observations were associated with it. If you have any questions or comments on animal species associations with vegetation communities, please contact the Montana Natural Heritage Program's Senior Zoologist.
Plant Species Associations
Please note that while diagnostic, dominant, or codominant vascular plant species for a vegetation community have been systematically assigned to those communities and vascular plant Species of Concern were systematically evaluated for their associations with vegetation communities, the majority of Montana’s vascular plant species have not been evaluated for their associations with vegetation communities and no attempt has been made to associate non-vascular plants, fungi, or lichens with vegetation communities. Plant species associations with natural vegetation communities were made in a manner similar to that described above for animals, but with review of Lesica et al. (2022) and specimen collection data from the Consortium of Pacific Northwest Herbaria. If you have any questions or comments on plant species associations with vegetation communities, please contact the Montana Natural Heritage Program's Program Botanist.
Suggested Uses and Limitations
Species associations with vegetation communities should be used to generate potential lists of species that may occupy broader landscapes for the purposes of landscape-level planning. These potential lists of species should not be used in place of documented occurrences of species or predicted habitat suitability models (this information can be requested at: https://mtnhp.mt.gov/requests/), or systematic surveys for species and onsite evaluations of habitat by trained biologists. Users of this information should be aware that the land cover data used to generate species associations is based on satellite imagery from 2016 and was only intended to be used at broader landscape scales. Land cover mapping accuracy is particularly problematic when the vegetation communities occur as small patches or where the land cover types have been altered over the past decade. Thus, particular caution should be used when using the associations in assessments of smaller areas (e.g., evaluations of public land survey sections). Finally, although a species may be associated with a particular vegetation community within its known geographic range, portions of that vegetation community may occur outside of the species' known geographic range.
Literature Cited
- Adams, R.A. 2003. Bats of the Rocky Mountain West; natural history, ecology, and conservation. Boulder, CO: University Press of Colorado. 289 p.
- Consortium of Pacific Northwest Herbaria. https://www.pnwherbaria.org/ Last accessed May 30, 2025.
- Dobkin, D. S. 1992. Neotropical migrant land birds in the Northern Rockies and Great Plains. USDA Forest Service, Northern Region. Publication No. R1-93-34. Missoula, MT.
- Foresman, K.R. 2012. Mammals of Montana. Second edition. Mountain Press Publishing, Missoula, Montana. 429 pp.
- Hart, M.M., W.A. Williams, P.C. Thornton, K.P. McLaughlin, C.M. Tobalske, B.A. Maxell, D.P. Hendricks, C.R. Peterson, and R.L. Redmond. 1998. Montana atlas of terrestrial vertebrates. Montana Cooperative Wildlife Research Unit, University of Montana, Missoula, MT. 1302 p.
- Hutto, R.L. and J.S. Young. 1999. Habitat relationships of landbirds in the Northern Region, USDA Forest Service, Rocky Mountain Research Station RMRS-GTR-32. 72 p.
- Lesica P., M. Lavin, and P.F. Stickney. 2022. Manual of vascular plants, 2nd Edition. Brit Press. 779 p.
- Maxell, B.A. 2000. Management of Montana's amphibians: a review of factors that may present a risk to population viability and accounts on the identification, distribution, taxonomy, habitat use, natural history, and the status and conservation of individual species. Report to U.S. Forest Service Region 1. Missoula, MT: Wildlife Biology Program, University of Montana. 161 p.
- Werner, J.K., B.A. Maxell, P. Hendricks, and D. Flath. 2004. Amphibians and reptiles of Montana. Missoula, MT: Mountain Press Publishing Company. 262 p.
- Species of Concern Associated with this Community
Vascular Plants
Mammals
Birds
Reptiles
Amphibians
- Diagnostic, Dominant, or Codominant Plant Species for this Community
Vascular Plants
- Other Native Species Commonly Associated with this Community
Vascular Plants
Original Concept Authors
D.H. Knight (1994) and M.S. Reid and K.A. Schulz
Montana Version Authors
S. Mincemoyer
Version Date
12/3/2024
References
- Literature Cited AboveLegend:
View Online Publication
Asebrook, J.M. 2006. Revegetation Monitoring Reports: Glacier National Park. West Glacier, MT: Research Reports, Glacier National Park.- Asebrook, J.M., J. Lapp, and T. Carolin. 2011. Whitebark and limber pine restoration and monitoring in Glacier National Park. Pp. 335-337 In: Proceedings of the high five symposium on the future of high-elevation, five-needle white pines in western North America, Keane, R.E., Tomback, D.F., Murray, M.P., and Smith, C.M. Missoula, MT: USDA Forest Service, Rocky Mountain Research Station. RMRS-P-63.
- Bureau of Land Management (BLM). 2011 Whitebark and Limber Pine (Five Needle Pine) Management Guidelines for Wyoming BLM. In: FY 2011 Memorandums. Wyoming: U.S. Department of the Interior, Bureau of Land Management.
- Burns, R. M., and B. H. Honkala, technical coordinators. 1990a. Silvics of North America: Volume 1. Conifers. USDA Forest Service. Agriculture Handbook 654. Washington, DC. 675 pp.
- DeVelice, R.L. and P. Lesica. 1993. Plant community classification for vegetation on BLM lands, Pryor Mountains, Carbon County, Montana. Montana Natural Heritage Program, Helena, MT. 78 pp.
- Fischer, W.C. and B.D. Clayton. 1983. Fire ecology of Montana. Forest habitat types east of the continental divide. USDA, Forest Service Gen. Tech. Rpt. INT-141.
- Hoff, R.J. and G.I. McDonald. 1993. Variation of virulence of white pine blister rust. European journal of forest pathology 23(2):103-109.
- Jackson, M., A. Gannon, H. Kearns, K. Kendall. 2010. Current Status of Limber Pine in Montana. Report 10-06. Missoula, MT: U.S. Department of Agriculture, Forest Service, Northern Region. 14 p.
- Means, R.E. 2010. Synthesis of lower treeline limber pine (Pinus flexilis) woodland knowledge, research needs, and management considerations. Pp. 29-36 In: Proceedings of the high five symposium on the future of high-elevation, five-needle white pines in western North America, Keane, R.E., Tomback, D.F., Murray, M.P., and Smith, C.M. Missoula, MT: USDA Forest Service, Rocky Mountain Research Station. RMRS-P-63.
- Pfister, R. D., B. L. Kovalchik, S. F. Arno, and R. C. Presby. 1977. Forest habitat types of Montana. USDA Forest Service. General Technical Report INT-34. Intermountain Forest and Range Experiment Station, Ogden, UT. 174 pp.
- Scher, J.S. 2002. Juniperus scopulorum. In: Fire Effects Information System, [Online]. U.S. Department of Agriculture, Forest Service, Rocky Mountain Research Station, Fire Sciences Laboratory.
- Schoettle, A.W. and R.A. Sniezko. 2007. Proactive intervention to sustain high-elevation pine ecosystems threatened by white pine blister rust. Journal of Forest Research 12(5):327-336.
- Schoettle, A.W., R.A. Sniezko, R.A., A. Kegley, and K.S. Burns. 2014. White pine blister rust resistance in limber pine: evidence for a major gene. Phytopathology 104(2):163-173.
- Schuster, W.S., J.B. Mitton, D.K. Yamaguchi, and C.A. Woodhouse. 1995. A comparison of limber pine (Pinus flexilis) ages at lower and upper treeline sites east of the Continental Divide in Colorado. American Midland Naturalist 133(1):101-111.
- U.S. Department of Agriculture, Forest Service, Missoula Fire Sciences Laboratory. 2012. Information from LANDFIRE on Fire Regimes of Limber Pine Communities. In: Fire Effects Information System. Missoula, MT: USDA Forest Service, Rocky Mountain Research
- Additional ReferencesLegend: View Online Publication
Do you know of a citation we're missing?- Cooper, S.V., C. Jean, and B.L. Heidel. 1999. Plant associations and related botanical inventory of the Beaverhead Mountains Section, Montana. Unpublished report to the Bureau of Land Management. Montana Natural Heritage Program, Helena. 235 pp.
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