Northern Rockies Subalpine Grassland

EVT 7146Southern Rocky Mountain Montane-Subalpine Grassland
CES306.806GNRHerbGrassland
Summary
This is an upper montane to subalpine, high-elevation, lush grassland system dominated by perennial grasses and forbs on dry sites, particularly south-facing slopes. It is most extensive in the Canadian Rockies portion of the Rocky Mountain cordillera, extending south into western Montana, eastern Oregon, eastern Washington and Idaho. Subalpine dry grasslands are small meadows to large open parks surrounded by conifer trees but lack tree cover within them. In general, soil textures are much finer, and soils are often deeper under grasslands than in the neighboring forests. Grasslands, although composed primarily of tussock-forming species, do exhibit a dense sod that makes root penetration difficult for tree species. Disturbance such as fire also plays a role in maintaining these open grassy areas. Typical dominant species include Leymus innovatus, Koeleria macrantha, Festuca campestris, Festuca idahoensis, Festuca viridula, Achnatherum occidentale, Achnatherum richardsonii, Bromus inermis var. pumpellianus, Elymus trachycaulus, Phleum alpinum, Trisetum spicatum, and a variety of Carices, such as Carex hoodii, Carex obtusata, and Carex scirpoidea. Important forbs include Lupinus argenteus var. laxiflorus, Potentilla diversifolia, Potentilla flabellifolia, Fragaria virginiana, and Chamerion angustifolium. This system is similar to Northern Rocky Mountain Lower Montane, Foothill and Valley Grassland (CES306.040) but is found at higher elevations and is more often composed of species of Festuca, Achnatherum, and/or Hesperostipa with additional floristic components of more subalpine taxa. Occurrences of this system are often more forb-rich than Southern Rocky Mountain Montane-Subalpine Grassland (CES306.824).
Source: NatureServe Explorer
Vegetation
Grasslands, although composed primarily of tussock-forming species, do exhibit a dense sod that makes root penetration difficult for tree species. Typical dominant species include Leymus innovatus (= Elymus innovatus), Koeleria macrantha, Festuca campestris, Festuca idahoensis, Festuca viridula, Achnatherum occidentale (= Stipa occidentalis), Achnatherum richardsonii (= Stipa richardsonii), Bromus inermis var. pumpellianus (= Bromus pumpellianus), Elymus trachycaulus, Phleum alpinum, Trisetum spicatum, and a variety of Carices, such as Carex hoodii, Carex obtusata, and Carex scirpoidea. Important forbs include Lupinus argenteus var. laxiflorus, Potentilla diversifolia, Potentilla flabellifolia, Fragaria virginiana, and Chamerion angustifolium (= Epilobium angustifolium).
Source: NatureServe Explorer
Environment
This is an upper montane to subalpine, high-elevation, lush grassland system dominated by perennial grasses and forbs on dry sites, particularly south-facing slopes. It is most extensive in the Canadian Rockies portion of the Rocky Mountain cordillera, extending south into western Montana, eastern Oregon, eastern Washington and Idaho. Subalpine dry grasslands are small meadows to large open parks surrounded by conifer trees but lack tree cover within them. In general, soil textures are much finer, and soils are often deeper under grasslands than in the neighboring forests.
Source: NatureServe Explorer
Dynamics
Disturbance such as fire also plays a role in maintaining these open grassy areas.
Source: NatureServe Explorer
Distribution
This system is most extensive in the Canadian Rockies portion of the Rocky Mountain cordillera, extending south into western Montana, central and eastern Oregon, eastern Washington and Idaho. It also occurs in the "island" ranges of central Montana, though it is not common, and is also found in the Bighorn Range of north-central Wyoming.
Source: NatureServe Explorer
Ecologically Associated Plant Species

Plant species that characterize this ecosystem type, organized by vegetation stratum. These are species ecologically associated with the ecosystem, not confirmed present in any specific area.

Herb (field)

Achnatherum occidentale, Achnatherum richardsonii, Agoseris glauca, Bromus inermis ssp. pumpellianus, Carex geyeri, Carex hoodii, Carex obtusata, Carex scirpoidea, Chamaenerion angustifolium, Danthonia intermedia, Elymus trachycaulus, Festuca campestris, Festuca idahoensis, Festuca viridula, Fragaria virginiana, Koeleria macrantha, Leymus innovatus, Lupinus argenteus var. laxiflorus, Phleum alpinum, Potentilla diversifolia, Potentilla flabellifolia, Trisetum spicatum
Source: NatureServe Ecological System assessment
Ecologically Associated Animals (3)

Animal species ecologically associated with this ecosystem type based on NatureServe assessment. These are species whose habitat requirements overlap with this ecosystem, not confirmed present in any specific roadless area.

Mammals (2)

Common NameScientific NameG-Rank
Montane VoleMicrotus montanusG5
Columbian Ground SquirrelUrocitellus columbianusG5

Reptiles (1)

Common NameScientific NameG-Rank
Terrestrial GartersnakeThamnophis elegansG5
Source: NatureServe Ecological System assessment
Component Associations (14)

Plant community associations that occur within this ecological system. Associations are the finest level of the U.S. National Vegetation Classification (USNVC) and describe specific, repeating assemblages of plant species. Each association represents a distinct community type that may be found where this ecosystem occurs.

NameG-Rank
Calamagrostis rubescens GrasslandG3 NatureServe
Carex hoodii - Festuca idahoensis GrasslandG2 NatureServe
Festuca campestris GrasslandG3 NatureServe
Festuca idahoensis - Carex filifolia GrasslandG3 NatureServe
Festuca idahoensis - Carex obtusata GrasslandG3 NatureServe
Festuca idahoensis - Carex scirpoidea GrasslandG2 NatureServe
Festuca idahoensis - Danthonia intermedia GrasslandG3 NatureServe
Festuca idahoensis - Deschampsia cespitosa GrasslandG3 NatureServe
Festuca idahoensis - Elymus trachycaulus GrasslandG4 NatureServe
Festuca idahoensis - (Festuca campestris) / Potentilla diversifolia GrasslandG3 NatureServe
Festuca viridula - Carex hoodii MeadowG3 NatureServe
Festuca viridula - Festuca idahoensis MeadowG2 NatureServe
Festuca viridula - Lupinus argenteus var. laxiflorus MeadowG3 NatureServe
Phleum alpinum - Elymus trachycaulus MeadowG2 NatureServe
State Conservation Ranks (5)

Subnational conservation status ranks (S-ranks) assigned by Natural Heritage Programs in each state where this ecosystem occurs. S1 indicates critically imperiled at the state level, S2 imperiled, S3 vulnerable, S4 apparently secure, and S5 secure. An ecosystem may be globally secure but imperiled in specific states at the edge of its range.

StateS-Rank
IDSNR
MTSNR
ORSNR
WASNR
WYSNR
Roadless Areas (187)

Inventoried Roadless Areas where this ecosystem is present, identified from LANDFIRE 2024 Existing Vegetation Type spatial analysis. Coverage indicates the proportion of each area occupied by this ecosystem type.

Arizona (2)

AreaForestCoverageHectares
Black River CanyonApache-Sitgreaves National Forests1.4%67.5
Red PointKaibab National Forest1.0%29.07

California (5)

AreaForestCoverageHectares
Iceberg - SlinkardHumboldt-Toiyabe National Forest5.6%35.01
Fourth Of July Spr (CA)Humboldt-Toiyabe National Forest2.1%22.86
Wild Horse Mtn. (CA)Humboldt-Toiyabe National Forest1.1%130.5
FalesHumboldt-Toiyabe National Forest1.0%36.18
Boundary Peak (CA)Inyo National Forest0.3%286.38

Nevada (52)

AreaForestCoverageHectares
Jarbidge - SeventysixHumboldt-Toiyabe National Forest29.0%77.31
Hicks MountainHumboldt-Toiyabe National Forest8.3%550.62
Pine Mtn.Humboldt-Toiyabe National Forest7.7%390.51
Pennsylvania HillHumboldt-Toiyabe National Forest7.5%239.13
Copper Mtns.Humboldt-Toiyabe National Forest6.9%886.86
Humboldt - Checkers NEHumboldt-Toiyabe National Forest6.5%16.74
Humboldt - Angel LkHumboldt-Toiyabe National Forest6.4%26.19
Deadhorse PointHumboldt-Toiyabe National Forest6.0%227.34
RattlesnakeHumboldt-Toiyabe National Forest5.8%463.95
Ruby - Cold CkHumboldt-Toiyabe National Forest4.6%43.83
Ruby - SegundaHumboldt-Toiyabe National Forest3.8%194.13
Elephant ButtesHumboldt-Toiyabe National Forest3.7%94.77
Jarbidge - CottonwoodHumboldt-Toiyabe National Forest3.6%52.29
Ruby - Lamoille CynHumboldt-Toiyabe National Forest3.5%465.03
McaffieHumboldt-Toiyabe National Forest3.0%316.17
Pearl PeakHumboldt-Toiyabe National Forest2.8%799.47
Boulder BasinHumboldt-Toiyabe National Forest2.7%75.42
Ruby - SouthHumboldt-Toiyabe National Forest2.6%137.88
Ruby - Smith CkHumboldt-Toiyabe National Forest2.5%76.59
Jarbidge - Biroth RdgHumboldt-Toiyabe National Forest2.3%46.44
Cabin CreekHumboldt-Toiyabe National Forest2.3%97.83
Santa RosaHumboldt-Toiyabe National Forest2.2%481.41
Ruby - MarshHumboldt-Toiyabe National Forest2.1%85.41
Duck Creek Mtns.Humboldt-Toiyabe National Forest2.0%99.99
Jarbidge - Sun CreekHumboldt-Toiyabe National Forest2.0%70.38
Staunton RidgeHumboldt-Toiyabe National Forest1.9%81.45
Elk MountainHumboldt-Toiyabe National Forest1.8%62.1
Bunker HillHumboldt-Toiyabe National Forest1.7%195.21
South Fork QuinnHumboldt-Toiyabe National Forest1.7%281.25
Boundary Peak (NV)Inyo National Forest1.6%142.83
Jenneman PeakHumboldt-Toiyabe National Forest1.5%39.24
South SchellHumboldt-Toiyabe National Forest1.5%757.62
Hot Springs ButteHumboldt-Toiyabe National Forest1.5%46.53
Flat CreekHumboldt-Toiyabe National Forest1.4%31.95
Toiyabe RangeHumboldt-Toiyabe National Forest1.3%528.57
West SchellHumboldt-Toiyabe National Forest1.3%112.68
South Shoshone PeakHumboldt-Toiyabe National Forest1.2%122.22
WildhorseHumboldt-Toiyabe National Forest1.2%55.8
VincentiHumboldt-Toiyabe National Forest1.2%39.42
North SchellHumboldt-Toiyabe National Forest1.1%141.84
Jarbidge - Pete BasinHumboldt-Toiyabe National Forest1.1%23.49
RobinsonHumboldt-Toiyabe National Forest1.1%32.85
South ForkHumboldt-Toiyabe National Forest1.0%44.91
Bald Mtn.Humboldt-Toiyabe National Forest1.0%173.43
Ruby - Secret Pk.Humboldt-Toiyabe National Forest1.0%28.08
Humboldt - SouthHumboldt-Toiyabe National Forest1.0%44.55
SugarloafInyo National Forest0.9%40.59
Mt. HicksHumboldt-Toiyabe National Forest0.8%49.86
East Fork QuinnHumboldt-Toiyabe National Forest0.8%97.83
ButtermilkHumboldt-Toiyabe National Forest0.7%53.1
ShellbackHumboldt-Toiyabe National Forest0.5%77.85
Pine Grove SouthHumboldt-Toiyabe National Forest0.3%110.97

New Mexico (24)

AreaForestCoverageHectares
Ranger CabinCibola National Forest25.1%621.9
RendijaSanta Fe National Forest23.5%206.55
T BarGila National Forest20.1%555.75
Oser MesaCarson National Forest9.3%107.1
Cruces BasinCarson National Forest8.3%175.95
GallinasSanta Fe National Forest7.7%409.59
Mt. TaylorCibola National Forest7.5%193.68
Jacks CreekSanta Fe National Forest6.6%19.8
Grass MountainSanta Fe National Forest5.6%73.8
Willow CreekSanta Fe National Forest4.0%23.85
Elk MountainGila National Forest3.9%104.4
Pecos WS RiverSanta Fe National Forest3.5%77.04
Valle Del ToroSanta Fe National Forest3.2%23.94
Canyon CreekGila National Forest3.1%125.01
Bear MountainSanta Fe National Forest2.7%15.12
Guaje CanyonSanta Fe National Forest2.3%56.52
Contiguous To Gila Wilderness & Primitive AreaGila National Forest2.1%658.89
Rio MedioSanta Fe National Forest1.9%21.78
Alamo CanyonSanta Fe National Forest1.7%57.69
El LagunitoSanta Fe National Forest1.6%43.2
Eagle PeakGila National Forest1.3%175.77
Polvadera PeakSanta Fe National Forest1.2%31.05
Columbine - Hondo Wilderness Study AreaCarson National Forest0.7%122.85
Contiguous To Black & Aldo Leopold WildernessGila National Forest0.3%127.98

Utah (85)

AreaForestCoverageHectares
418042Uinta National Forest10.9%323.01
Rolfson - StakerManti-Lasal National Forest10.9%308.61
White MountainManti-Lasal National Forest9.0%259.11
0401029Ashley National Forest8.5%231.93
418034Uinta National Forest7.9%196.65
418044Uinta National Forest7.8%173.88
418003Uinta National Forest5.8%258.21
418004Uinta National Forest5.8%388.8
HeliotropeManti-Lasal National Forest5.6%102.15
Black MountainManti-Lasal National Forest5.3%137.52
Mt. Um Plateau - Mt TerrillFishlake National Forest4.7%334.98
0401023Ashley National Forest3.8%128.88
Stansbury MountainsWasatch-Cache National Forest3.5%561.6
Big Bear CreekManti-Lasal National Forest3.5%401.85
Blue MountainManti-Lasal National Forest3.0%261.9
Boulger - Black CanyonManti-Lasal National Forest2.9%271.26
White KnollManti-Lasal National Forest2.9%159.93
Sugar PineWasatch-Cache National Forest2.8%64.17
Musinia PeakFishlake National Forest2.5%69.39
Widdop MountainWasatch-Cache National Forest2.5%80.28
Oak CreekFishlake National Forest2.3%504.09
White MountainFishlake National Forest2.3%218.61
418022Uinta National Forest2.2%152.37
Lamb CanyonWasatch-Cache National Forest2.1%36.36
Rock Creek - Green ForkWasatch-Cache National Forest2.1%47.43
Twelve Mile CreekManti-Lasal National Forest2.0%82.71
Upper South ForkWasatch-Cache National Forest1.9%132.66
Bullion - DelanoFishlake National Forest1.9%117.54
Hay LakesDixie National Forest1.9%165.96
North HornManti-Lasal National Forest1.7%58.41
418013Uinta National Forest1.7%100.08
Price RiverManti-Lasal National Forest1.5%151.83
0401027Ashley National Forest1.5%45.18
Musinia PeakManti-Lasal National Forest1.5%29.52
418043Uinta National Forest1.5%57.87
Lost PeakDixie National Forest1.5%24.3
Deer CreekDixie National Forest1.4%227.52
418025Uinta National Forest1.4%185.49
Circleville MountainFishlake National Forest1.4%132.84
418019Uinta National Forest1.3%36.54
Dark ValleyDixie National Forest1.2%137.88
418001Uinta National Forest1.2%28.17
418031Uinta National Forest1.2%89.64
Raft RiverSawtooth National Forest1.2%117.09
0401014Ashley National Forest1.2%130.77
Horse Mountain - Mans PeakManti-Lasal National Forest1.2%106.56
418009Uinta National Forest1.2%86.58
Wildcat KnollsManti-Lasal National Forest1.2%24.66
418041Uinta National Forest1.2%79.2
418002Uinta National Forest1.2%90.45
Swan Creek MountainWasatch-Cache National Forest1.2%43.92
Mollens HollowWasatch-Cache National Forest1.1%80.82
Fishlake MountainFishlake National Forest1.0%100.35
Mt. PealeManti-Lasal National Forest1.0%38.07
Mt. Johns Peak - Mt AliceFishlake National Forest0.9%47.88
418006Uinta National Forest0.9%42.57
Mt. Logan SouthWasatch-Cache National Forest0.9%58.95
418032Uinta National Forest0.8%50.85
SanpitchManti-Lasal National Forest0.8%94.41
Boulder Mtn. / Boulder Top / Deer LakeDixie National Forest0.8%357.03
Muddy Creek - Nelson Mt.Manti-Lasal National Forest0.8%188.73
0418033Ashley National Forest0.8%78.84
418029Uinta National Forest0.8%49.23
0401007Ashley National Forest0.8%51.39
418016Uinta National Forest0.8%109.26
Casto BluffDixie National Forest0.8%266.22
418018Uinta National Forest0.7%33.75
418012Uinta National Forest0.7%75.87
South MountainManti-Lasal National Forest0.7%42.3
0401008Ashley National Forest0.7%42.84
PavantFishlake National Forest0.7%115.83
418015Uinta National Forest0.6%45.27
Big HorseshoeManti-Lasal National Forest0.6%45.72
0401005Ashley National Forest0.6%100.98
418024Uinta National Forest0.6%127.35
0419020Ashley National Forest0.6%875.07
Long Neck Mesa / Steep Creek / Oak Creek - Steep Creek / OakDixie National Forest0.6%135.09
North PavantFishlake National Forest0.6%121.32
0401002Ashley National Forest0.6%81.72
Hilgard MountainFishlake National Forest0.5%60.39
418028Uinta National Forest0.4%61.92
Tushar MountainFishlake National Forest0.4%71.37
Mt. NaomiWasatch-Cache National Forest0.4%73.44
High Uintas (UT)Wasatch-Cache National Forest0.4%168.57
LakesWasatch-Cache National Forest0.3%167.58

Wyoming (19)

AreaForestCoverageHectares
Illinois CreekMedicine Bow-Routt National Forest12.3%333
Platte River AdditionMedicine Bow-Routt National Forest8.8%282.78
Bear MountainMedicine Bow-Routt National Forest5.3%203.04
Sheep MountainMedicine Bow-Routt National Forest4.0%285.57
Savage Run AdditionMedicine Bow-Routt National Forest3.5%33.57
Snowy RangeMedicine Bow-Routt National Forest3.5%420.3
Libby FlatsMedicine Bow-Routt National Forest3.2%144.45
French CreekMedicine Bow-Routt National Forest3.1%74.79
Campbell LakeMedicine Bow-Routt National Forest3.0%86.76
Bridger PeakMedicine Bow-Routt National Forest2.9%79.47
Laramie PeakMedicine Bow-Routt National Forest2.4%274.05
Middle ForkMedicine Bow-Routt National Forest1.8%95.67
Little SandstoneMedicine Bow-Routt National Forest1.4%30.96
Big SandstoneMedicine Bow-Routt National Forest1.3%38.97
Cow Creek MountainMedicine Bow-Routt National Forest1.2%40.59
Soldier CreekMedicine Bow-Routt National Forest1.1%27
Rock CreekMedicine Bow-Routt National Forest1.1%82.62
Pennock MountainMedicine Bow-Routt National Forest1.0%38.88
Huston Park AdditionMedicine Bow-Routt National Forest0.9%31.41
Methodology and Data Sources

Ecosystem classification: Ecosystems are classified using the LANDFIRE 2024 Existing Vegetation Type (EVT) layer, mapped to NatureServe Terrestrial Ecological Systems via a curated crosswalk. Each EVT is linked to the USNVC (U.S. National Vegetation Classification) hierarchy through pixel-level co-occurrence analysis of LANDFIRE EVT and NatureServe IVC Group rasters across all roadless areas.

Vegetation coverage: Coverage percentages and hectares are derived from zonal statistics of the LANDFIRE 2024 EVT raster intersected with roadless area boundaries.

Ecosystem narratives and community species: Sourced from the NatureServe Explorer API, representing professional ecological assessments of vegetation composition, environmental setting, dynamics, threats, and characteristic species assemblages.

IVC hierarchy: The International Vegetation Classification hierarchy is sourced from the USNVC v3.0 Catalog, providing the full classification from Biome through Association levels.

Component associations: Plant community associations listed as components of each NatureServe Ecological System. Association data from the NatureServe Explorer API.

State ranks: Conservation status ranks assigned by NatureServe member programs in each state where the ecosystem occurs.