Rocky Mountain Cliff, Canyon and Massive Bedrock
Provisional State Rank
(see reason below)
State Rank Reason
Because these systems tend to occur in inaccessible locations, they have not been widely disturbed. However, warming and/or drying climatic patterns and loss of tree species to fire or insects may limit the range and distribution over the short term.
This ecological system of barren and sparsely vegetated landscapes is found from foothill to subalpine elevations throughout the Rocky Mountains and island mountain ranges of Montana. Its range overlaps with the Western Great Plains Cliff and Outcrop, which differs in having more developed soils and more vegetated cover. It occurs on steep cliff faces, in narrow canyons, and on smaller rock outcrops of various igneous, sedimentary, and metamorphic bedrock types, and includes the unstable scree and talus slopes that typically occur below cliff faces. It is characteristically dry and sparsely vegetated, typically having less than 10% plant cover. Although there may be small patches of dense vegetation, the system usually consists of scattered trees and/or shrubs such as Douglas-fir (Pseudotsuga menziesii), Ponderosa pine (Pinus ponderosa), limber pine (Pinus flexilis), aspen (Populus tremuloides), or subalpine fir (Abies lasiocarpa). Juniper (Juniperus spp.) is common at lower elevations. Shrubs adapted to xeric growing conditions and rocky soils are typically present, e.g. oceanspray (Holodiscus discolor), currant (Ribes species), common ninebark (Physocarpus malvaceus), wild rose (Rosa species), common juniper (Juniperus communis), Lewis mock orange (Philadelphus lewisii), creeping Oregon grape (Mahonia repens), three leaf sumac (Rhus trilobata), American wild raspberry (Rubus idaeus) or serviceberry (Amelanchier alnifolia). Soil development is limited, as is herbaceous cover. Forbs may include penstemon (Penstemon species), buckwheat (Eriogonum species), western sagewort (Artemisia ludovicana), Michaux’s sagewort (Artemisia michauxiana), and spotted saxifrage (Saxifraga bronchialis). Because the elevation range is so broad, species composition may vary widely from occurrence to occurrence.
Canyon, cliff, bedrock outcrop, barrens or talus; shallow and/or poorly developed soils; less than 10% vascular plant cover.
This system is located throughout the Rocky Mountains, including the mountains of western Montana and the isolated island ranges of central Montana.
Ecological System Distribution
Approximately 691 square kilometers are classified as Rocky Mountain Cliff, Canyon and Massive Bedrock in the 2017 Montana Land Cover layers.
Grid on map is based on USGS 7.5 minute quadrangle map boundaries.
Montana Counties of Occurrence
Beaverhead, Big Horn, Blaine, Broadwater, Carbon, Cascade, Chouteau, Deer Lodge, Fergus, Flathead, Gallatin, Glacier, Golden Valley, Granite, Hill, Jefferson, Judith Basin, Lake, Lewis and Clark, Liberty, Lincoln, Madison, Meagher, Mineral, Missoula, Park, Phillips, Pondera, Powell, Ravalli, Sanders, Silver Bow, Stillwater, Sweet Grass, Teton, Toole, Wheatland
The Rocky Mountain Cliff, Canyon and Massive Bedrock ecological system occurs on steep cliff faces, in narrow canyons, on smaller rock outcrops and on unstable scree and talus slopes. These systems are shaped by the parent rock material, climate, aspect, and physical weathering patterns making them distinct from neighboring ecosystems as well as from each other (Larson et al 2000). Soils are typically thin and/or poorly developed, and moisture for plant growth is primarily retained in crevices in the rock substrate. Limited soil availability, harsh weather extremes, and water stress impose physiological constraints on plants communities leading to plant species that are uniquely adapted to these conditions. Additionally, within the larger cliff habitat, steep slopes, small ledges, overhangs, cracks and crevices often form a mosaic of microhabitat types (Graham and Knight 2004).
This system is characteristically dry and sparsely vegetated, typically having less than 10% plant cover. Species composition includes individuals present in adjacent systems (unless exposed parent material is radically different) and herbaceous species specifically adapted to cliff faces and unstable talus slides. Soil development is limited, as is herbaceous cover. Although there may be small patches of dense vegetation, the system usually consists of scattered trees and/or shrubs such as Douglas-fir (Pseudotsuga menziesii), Ponderosa pine (Pinus ponderosa), limber pine (Pinus flexilis), aspen (Populus tremuloides), or subalpine fir (Abies lasiocarpa). Juniper (Juniperus spp.) is common at lower elevations. Shrubs adapted to xeric growing conditions and rocky soils are typically present, e.g. oceanspray (Holodiscus discolor), currant (Ribes species), common ninebark (Physocarpus malvaceus), wild rose (Rosa species), common juniper (Juniperus communis), Lewis mock orange (Philadelphus lewisii), creeping Oregon grape (Mahonia repens), three leaf sumac (Rhus trilobata), American wild raspberry (Rubus idaeus) or serviceberry (Amelanchier alnifolia). Woody colonizing vegetation is usually limited to the toeslopes of talus and scree slides or in protected pockets beneath cliff faces. Herbaceous plants inhabit both the talus and scree slides and fractures in the cliff faces. Forbs may include penstemon (Penstemon species), buckwheat (Eriogonum species), western sagewort (Artemisia ludovicana), Michaux’s sagewort (Artemisia michauxiana), and spotted saxifrage (Saxifraga bronchialis). Graminoids may include slender wheatgrass (Elymus trachycaulus) and bluebunch wheatgrass (Pseudoroegneria spicata). Mosses and xeric-adapted ferns such as cliff fern (Woodsia species), holly fern (Polystichium lonchitis), and fragile fern (Cystopteris fragilis) occur in fractures of the bedrock, cliff faces or in toeslopes of unstable talus slides. Lichen cover can be high on larger size talus.
National Vegetation Classification Switch to Full NVC View
Adapted from US National Vegetation Classification
A0540 Pinus flexilis Rocky Mountain Woodland Alliance
CEGL000815 Pinus flexilis Scree Woodland
A2036 Populus tremuloides Rocky Mountain Forest & Woodland Alliance
CEGL000945 Populus tremuloides - Physocarpus malvaceus / Amelanchier alnifolia Scree Woodland
A3154 Minuartia obtusiloba - Paronychia pulvinata - Silene acaulis Alpine Fell-field Alliance
A3398 Pinus ponderosa Southern Rocky Mountain Forest & Woodland Alliance
A3454 Pseudotsuga menziesii Southern Rocky Mountain Forest & Woodland Alliance
CEGL000911 Pseudotsuga menziesii Scree Woodland
A3466 Pinus ponderosa Northwest Great Plains Open Woodland Alliance
A3616 Abies lasiocarpa - Picea engelmannii Rocky Mountain Talus & Scree Woodland Alliance
A3644 Abies lasiocarpa - Picea engelmannii Dry-Mesic Scree & Talus Woodland Alliance
CEGL000925 Abies lasiocarpa Scree Woodland
A4021 Rocky Mountain Alpine Sparse Herb Bedrock & Scree Alliance
A4022 Rocky Mountain Alpine Nonvascular Bedrock & Scree Alliance
A4079 Pinus contorta Rocky Mountain Woodland Alliance
CEGL000766 Pinus contorta Scree Woodland
*Disclaimer: Alliances and Associations have not yet been finalized in the National Vegetation Classification (NVC) standard.
A complete version of the NVC for Montana can be found here
Cliff and canyon ecosystems are shaped by the strength and type of parent rock, aspect, climate, and both physical and chemical weathering patterns. Erosion by wind, water, and gravity is the primary disturbance process in these environment, and it can have a strong influence over which species occur on cliffs and talus (Larson et al 2000). Warming or drying climatic patterns will impact this system and the distribution of the peripheral species, northern Rocky Mountain endemics, and rare species that occur within it. Historically, stand-replacing fires occur frequently in adjacent forests, woodlands and shrublands. Lightning strikes can cause fire within these cliff and canyon systems, however due to minimal vegetation cover fire severity is generally low.
This system is fragile due to extremely limited soil development and plant colonization. Because they are difficult to access these habitats are relatively free of anthropogenic disturbance, however climbing recreation, and mining have been known to impact this system (Colorado Natural Heritage Program 2005).
Generally, human disturbances are extremely limited in this system due to inaccessibility and unstable landslides occurring below the cliff faces. Systems will generally recover over time if the disturbance is removed.
Species Associated with this Ecological System
- Details on Creation and Suggested Uses and Limitations
How Associations Were Made
We associated the use and habitat quality (common or occasional) of each of the 82 ecological systems mapped in Montana for
vertebrate animal species that regularly breed, overwinter, or migrate through the state 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, Foresman 2012, Adams 2003, and Werner et al. 2004);
- Evaluating structural characteristics and distribution of each ecological system 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 ecological system;
- Calculating the percentage of observations associated with each ecological system relative to the percent of Montana covered by each ecological system 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, and species that only migrate through Montana were only evaluated for migratory habitat use.
In general, species were listed as associated with an ecological system if structural characteristics of used habitat documented in the literature were present in the ecological system or large numbers of point observations were associated with the ecological system.
However, species were not listed as associated with an ecological system if there was no support in the literature for use of structural characteristics in an ecological system, even if
point observations were associated with that system.
Common versus occasional association with an ecological system was assigned based on the degree to which the structural characteristics of an ecological system matched the preferred structural habitat characteristics for each species as represented in scientific literature.
The percentage of observations associated with each ecological system relative to the percent of Montana covered by each ecological system was also used to guide assignment of common versus occasional association.
If you have any questions or comments on species associations with ecological systems, please contact the Montana Natural Heritage Program's Senior Zoologist.
Suggested Uses and Limitations
Species associations with ecological systems 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 (this information can be requested at: mtnhp.org/requests
) or systematic surveys for species and evaluations of habitat at a local site level by trained biologists.
Users of this information should be aware that the land cover data used to generate species associations is based on imagery from the late 1990s and early 2000s and was only intended to be used at broader landscape scales.
Land cover mapping accuracy is particularly problematic when the systems 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 ecological system within its known geographic range, portions of that ecological system may occur outside of the species' known geographic range.
- Adams, R.A. 2003. Bats of the Rocky Mountain West; natural history, ecology, and conservation. Boulder, CO: University Press of Colorado. 289 p.
- 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.
- 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.
- Native Species Commonly Associated with this Ecological System
- Native Species Occasionally Associated with this Ecological System
Montana Version Authors
- Classification and Map Identifiers
Cowardin Wetland Classification:
National Land Cover Dataset:
|Element Global ID
|CES306.815, Rocky Mountain Cliff, Canyon and Massive Bedrock
31: Barren Land
3129: Rocky Mountain Cliff, Canyon and Massive Bedrock
- Additional ReferencesLegend: View Online Publication
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