VEGETATION APPENDIX

VEGETATION APPENDIX

VEG-1

VEGETATION APPENDIX 

Habitat Types and 

Biological Diversity

The land classification system developed by the 

University of Montana, Montana Gap Analysis Project 

(MT-GAP), was used to estimate acreages listed for 

this Appendix (Fisher et al. 1998).

Grasslands

Grasslands cover approximately 7.9 million acres of 

the 13-county CBNG Planning Area. Of this acreage, 

2.6 million acres are underlain by subbituminous or 

bituminous coal deposits. Grasslands are divided into 

five types (see Table VEG-1). Species richness data for 

these types are provided.

Altered herbaceous habitats include grasslands with 

30 percent or more cover from introduced species 

and/or noxious weed species such as thistle (Cirsium

spp.), cheat grass (Bromus tectorum), Japanese brome 

(B. japonicus), spotted knapweed (Centaurea 

maculosa), crested wheatgrass (Agropyron cristatum) 

or yellow sweetclover (Melilotus officinalis). Total 

herbaceous cover ranges from 20 to 80 percent on these 

sites, which are usually associated with disturbance and 

can have bare ground coverages in the 10 to 50 percent 

range (Fisher et al. 1998). 

Very Low Cover Grasslands are semi-desert 

grasslands with total grass cover of 10 to 30 percent. 

They are dominated by short grasses and forbs such as 

blue grama (Bouteloua gracilis). These grasslands 

typically have a high amount of bare soil (20 to 

60 percent) (Fisher et al. 1998). 

Low to Moderate Cover Grasslands are the most 

abundant grassland type in Montana. They are the 

category that has the greatest potential for impact from 

CBM extraction (see Table VEG-1). Total grass 

coverages on these sites range from 20 to 70 percent 

and are dominated by short- to medium-height grasses 

and forbs, such as blue grama, green needlegrass (Stipa 

viridula), Idaho fescue (Festuca idahoensis), lupine 

(Lupinus spp.), arrowleaf balsamroot (Balsamorhiza 

sagittata), and bluebunch wheatgrass (Agropyron 

spicatum) (Fisher et al. 1998). 

Moderate to High Cover Grasslands are dominated 

by medium to tall grass species, such as bluebunch 

wheatgrass, green needlegrass, big bluestem 

(Andropogon gerardii), switchgrass (Panicum 

virgatum), little bluestem (Andropogon scoparium), 

and needle and thread (Stipa comata). Grass coverage 

on these grasslands ranges from 50 to 100 percent 

(Fisher et al. 1998). 

Montane Parklands and Subalpine Meadows are the 

final type of grasslands classification for Montana 

lands. Total herbaceous cover in these moist locations 

can range from 30 to 100 percent and are dominated by 

species such as beargrass (Xerophyllum tenax), several 

species of sedge (Carex spp.), pinegrass 

(Calamagrostis rubescens), arnica (Arnica spp.), and 

subalpine daisy (Erigeron peregrinus) (Fisher et al. 

1998).

Shrublands

Of the 4.8 million acres designated as shrubland in the 

CBNG Planning Area, approximately 1.7 million acres 

are underlain by bituminous coal deposits. Shrublands 

in Montana are divided into seven categories: Mixed 

Mesic Shrubs, Mixed Xeric Shrubs, Silver Sage, SaltDesert Shrubs, Mesic-Grassland Shrubs, XericGrassland Shrubs, and Sagebrush (see Table VEG-2). 

Mixed Mesic Shrub sites are characterized by 20 to 

100 percent shrub cover. Dominant shrubs on these 

sites are alder (Alnus spp.), ceanothus (Ceanothus spp), 

huckleberry (Vaccinium spp.), ninebark (Physocarpus 

malvaceus), snowberry (Symphoricarpos spp.), and 

western serviceberry (Amelanchier alnifolia). 

Mixed Xeric Shrub sites are characterized by shrub 

cover ranging from 20 to 50 percent. Dominant shrubs 

for this type are bitterbrush (Purshia tridentata), 

creeping juniper (Juniperus horizontalis), greasewood 

(Sarcobatus spp.), mountain mahogany (Cercocarpus

spp.), and rabbitbrush (Chrysothamnus spp.). 

Associated grass species cover from 5 to 40 percent of 

these sites and are predominantly bluebunch 

wheatgrass, blue grama, Idaho fescue, and western 

wheatgrass (Agropyron smithii). 

Silver Sage sites are dominated by silver sage 

(Artemisia cana). This alkali-tolerant species is most 

abundant in the northeastern part of Montana on moist 

sites near riparian areas. 

Salt-Desert Shrub and Dry Salt Flat sites are 

dominated by Saltsage (Atriplex nuttallii) at 10 to 

40 percent cover. These sites are usually underlain by 

alkali-affected soils in dry, sandy, or saline-seep areas. 

Species associated with these sites are blue grama, 

Sandberg’s bluegrass (Poa secunda), and threadleaf 

sedge (Carex filifolia). It occurs mainly in eastern and 

southeastern Montana.
VEGETATION APPENDIX

VEG-2

Mesic Shrub-Grassland Associations are shrublands 

with co-dominance between shrubs and grasses that 

together cover 10 to 50 percent of the site. These are 

moist, ecotonal areas between shrub-dominated and 

grass-dominated sites. The grass and shrub species are 

those found in the respective classes that make up the 

association. 

Xeric Shrub-Grassland Associations are shrublands 

with a co-dominance of xeric shrubs and grass species 

in the ecotone between grass- and xeric shrubdominated sites with the same dominant species as 

those types. Cover of both shrubs and grasses on these 

sites range from 10 to 50 percent.

Sagebrush shrubland sites are dominated by big 

sagebrush (Artemisia tridentata spp. tridentata, 

vaseyana, and wyomingensis) and black sagebrush 

(Artemisia nova) at 20 to 80 percent cover. These are 

associated with the same grass species listed under the 

Mixed Xeric Shrub habitat type. Sagebrush shrublands 

are particularly characteristic of the counties that make 

up the CBNG Planning Area where more than 33

percent (1.6 million acres) of shrublands fall within this 

category (Fisher et al. 1998).

Forests

Of the 2.8 million acres classified as forest in the 

CBNG Planning Area, almost 1.3 million acres are 

underlain by subbituminous or bituminous coal 

deposits. The acreages underlain with these coal beds

within each forest type in the 13 counties affected by 

this project are given in Table VEG-3.

Riparian Areas

Riparian areas cover about 1.0 million acres within the 

CBNG Planning Area. Almost 270,000 acres are 

underlain by subbituminous or bituminous coal beds.

Table VEG-4 gives the breakdown by type for riparian 

areas in the project area that are underlain by coal beds. 

The types with the most acreage are in the Graminoid 

and Forb and the Shrub categories. 

Graminoid and Forb Riparian areas are 

characterized by herbaceous species at 30 to 

100 percent cover and less than 15 percent cover of 

shrubs and trees. Standing water may be present in 

areas with cattail marshes. Plant species associated 

with this type are sedges (Carex spp.), cattails (Typha

spp.), reedgrass (Calamagrostis spp.), rushes (Juncus

spp.), saxifrage (Saxifraga spp.), and tufted hairgrass 

(Deschampsia caespitosa). 

Shrub Riparian sites are dominated by shrub cover at 

20 to 100 percent and tree cover at less than 15 percent. 

Standing water may be present in willow marshes in 

this category. Shrub species potentially present on 

shrub-dominated sites include alder (Alnus spp.), black 

hawthorn (Crataegus douglasii), birch (Betula spp.), 

currant (Ribes spp.), red-osier dogwood (Cornus 

stolonifera), rose (Rosa spp.), shrubby cinquefoil 

(Potentilla fruticosa), snowberry (Symphoricarpos

spp.), thimbleberry (Rubus parviflorum), twinberry 

(Lonicera involucrata), Utah honeysuckle (Lonicera 

utahensis), and willows (Salix spp.) (Fisher et al. 

1998).

Barren Lands

Table VEG-5 shows that one classification, Badlands, 

has a significant number of species associated with it.

Additional Tables

Additional Tables within this appendix include 

Tables VEG-6, VEG-7 and VEG-8; Table VEG-6 

shows critically imperiled plant species in the state 

with potential habitat in the CBNG Planning Area, 

Table VEG-7 shows noxious weeds found in the state, 

and Table VEG-8 indicates plant species of special 

concern by county within the project area.
VEGETATION APPENDIX

VEG-3

TABLE VEG-1

GRASSLAND TYPES AND ASSOCIATED WILDLIFE DIVERSITY

Grassland Types

Total Acres In Project 

Area With Underlying 

Subbituminous or

Bituminous Coal Beds Distribution

Species 

Richness*

Altered Herbaceous 

Habitats

36,969 Found throughout Montana, but most 

concentrated in the northeastern part of 

the state.

66

Very Low Cover 

Grasslands

202,556 Associated with alkaline soils or with 

disturbance.

68

Low to Moderate Cover 

Grasslands

2,170,236 Occurs across the state in valleys and 

foothills and on south aspects in the 

mountains.

78

Moderate to High Cover 

Grasslands

141,856 Associated with wet sites primarily in the 

valleys of central and eastern Montana.

72

Montane Parklands and 

Subalpine Meadows

7,323 Found at mid- to upper elevations either 

within forests or above timberline.

62

*Mean number of native terrestrial vertebrates species predicted by habitat type (Fisher et al. 1998). Species 

richness estimates are simple species counts and not intended to imply that areas with fewer species are not as 

important as areas with larger numbers of species.
VEGETATION APPENDIX

VEG-4

TABLE VEG-2

SHRUBLAND TYPES AND ASSOCIATED DISTRIBUTION AND SPECIES RICHNESS

Shrubland Types

Total Acres In Project 

Area With Underlying 

Subbituminous or

Bituminous Coal Beds Distribution

Species 

Richness*

Mixed Mesic Shrub 175,171 Found in western Montana and in draws or 

north slopes in eastern Montana

63

Mixed Xeric Shrub 668,043 Occur on dry rocky sites in valleys and low 

elevation mountain slopes.

75

Silver Sage 3,310 Primarily found in northeastern Montana on 

moist sites near riparian areas.

61

Salt-Desert Shrub and 

Dry Salt Flat

45,920 Usually associated with alkaline sites or 

blowouts in dry, sandy, or saline-seep areas 

in eastern Montana. 

29

Sagebrush 525,753 Occur across the state in valleys and low- to 

mid-elevational mountain slopes.

74

Mesic Shrub-Grassland 

Associations

116,813 Found in central and eastern Montana 

valleys and some low mountain slope areas 

in moist ecotonal areas between shrubdominated and grass-dominated sites.

75

Xeric Shrub-Grassland 

Associations

123,046 Occur primarily in eastern and central 

Montana valleys and some low mountain 

slopes on dry sites in valleys, in the ecotone 

between grass and xeric shrub dominated 

sites.

85

*Mean number of native terrestrial vertebrates species predicted by habitat type for Montana (Fisher et al. 1998).
VEGETATION APPENDIX

VEG-5

TABLE VEG-3

FOREST TYPES IN THE PROJECT AREA UNDERLAIN BY COAL BEDS

Forest Type

Total Acres In Project 

Area With Underlying 

Subbituminous or

Bituminous Coal Beds Distribution

Species 

Richness*

Douglas-fir

(Pseudotsuga 

menziesii)

16,726 Occurs across the state, except for the 

northeastern corner, but primarily found in 

western and south-central Montana.

77

Douglas-fir with 

Lodgepole Pine

228 Occurs in western and south-central Montana 

on mid-upper elevational slopes.

72

Limber Pine

(Pinus flexilis)

4,838 Dry forest sites at lower elevations in central 

Montana and at higher elevations on limestone 

soils in central and eastern Montana.

53

Lodgepole Pine

(Pinus contorta)

781 Occurs primarily in western and south-central 

Montana in mountainous regions at cooler, 

mid-high elevations.

65

Low Density Xeric 

Forest

303,312 Occurs primarily in eastern Montana on low 

hills on the edge of grasslands.

83

Mixed Broadleaf 

Forest

54,241 Occurs across the state, primarily in moist 

forest areas or near riparian areas or woody 

draws.

90

Mixed Broadleaf & 

Conifer Forest

27,761 Occurs across the state, primarily in moist 

forest areas, near riparian areas or in woody 

draws.

82

Mixed Subalpine 

Forest

643 Occurs at mid-high elevations in western and 

south-central Montana, usually on north, east, 

and northwest aspects.

67

Mixed Whitebark 

Pine Forest

10 Occurs in high elevation forest stands at or near 

tree line in western and south-central Montana.

39

Mixed Xeric Forest 24,910 Occurs at low-mid elevations on dry forest sites 

in western Montana.

76

Ponderosa Pine 840,850 Occurs across the state, except in northeastern 

Montana at lower elevations on dry forest sites.

79

Rocky Mountain 

Juniper

(Juniperus 

scopulorum)

3,984 Occurs primarily in central and eastern 

Montana on dry forest sites.

58

Standing Burnt Forest 2,099 Occurs across the state in forested areas and 

includes only stands that have burned in the 

5 years prior to 1998.

63

Utah Juniper

(Juniperus 

osteosperma)

4,953 Occurs primarily in central and eastern 

Montana on dry forest sites, particularly in 

Carbon County.

70

*Mean number of native terrestrial vertebrate species predicted by habitat type (Fisher et al. 1998).
VEGETATION APPENDIX

VEG-6

TABLE VEG-4

RIPARIAN AREAS IN THE PROJECT AREA UNDERLAIN BY COAL BEDS

Riparian Types

Total Acres In Project 

Area With Underlying 

Subbituminous or

Bituminous Coal Beds Distribution

Species 

Richness*

Conifer 138 Occurs in riparian areas in western 

and south-central Montana.

114

Broadleaf 36,797 Occurs in riparian areas across 

Montana.

123

Mixed Broadleaf & 

Conifer

6,131 Occurs in riparian areas of western 

and south-central Montana.

134

Graminoid & Forb 114,397 Occurs across the state. 72

Mixed Riparian 30,411 Occurs across the state 104

Shrub 80,233 Occurs across the state. 110

*Mean number of native terrestrial vertebrate species predicted by habitat type (Fisher et al. 1998).

TABLE VEG-5

BARREN LANDS

Barren Lands

Total Acres In Project 

Area With Underlying 

Subbituminous or

Bituminous Coal Beds Distribution

Species 

Richness*

Badlands 208,766 Occurs primarily in central and 

eastern Montana on sites where bare 

soil or rock is the dominant cover. 

Patches of grass or shrubs total less 

than 10 percent cover. Tree canopy is 

less than 10 percent on treed sites.

48

Mines, Quarries, Gravel 

Pits

15,247 Occurs across Montana and are as 

named.

13

Mixed Barren Sites 48,150 Occurs across the state where live 

vegetation provides less than 10 

percent cover.

17

Rock 24,563 Exposed rock, cliffs, talus slopes, or 

scree fields across the state.

14

*Mean number of native terrestrial vertebrate species predicted by habitat type (Fisher et al. 1998).
VEGETATION APPENDIX

VEG-7

TABLE VEG-6

STATE OF MONTANA CRITICALLY IMPERILED (S1) PLANT SPECIES WITH POTENTIAL HABITAT IN THE CBNG PLANNING AREA

Common Name (Scientific Name) Habitat

Daggett rock cress (Arabis demissa var languida) Canyon bottoms and outwash plains with dry, stony soils derived from limestone in juniper 

woodland.

Swamp milkweed (Asclepias incarnata) Wet meadows and thickets.

Ovalleaf milkweed (Asclepias ovalifolia) Open pine woodland in seasonally moist meadow in southeastern Montana.

Narrowleaf milkweed (Asclepias stenophylla) Sandy soils of prairies and open pine woodland in southeastern Montana.

Wind River milkvetch (Astragalus oreganus) Sandy or clayey soil in desert shrublands and sagebrush grassland in the valley zone in southcentral Montana.

Small camissonia (Camissonia parvula) Sandy calcareous soils of sagebrush steppe and juniper woodlands in the valleys.

Pregnant sedge (Carex gravida) Open woods, often in ravines with deciduous trees, on the plains of southeastern Montana.

Toothed Scandinavian sedge (Carex norvegica ssp. 

inserrulata)

Moist alpine turf.

Birchleaf mountain-mahogany (Cercocarpus montanus 

var. glaber)

Open slopes and breaks on the plains of eastern Montana.

Smooth goosefoot (Chenopodium subglabrum) Sparsely vegetated sand dunes and sandy terraces of major rivers on the plains of eastern 

Montana.

Yellow bee plant (Cleome lutea) Open, often-sandy soil of sagebrush steppe in the valleys.

Miner’s candle (Cryptantha scoparia) Sandy soil of sagebrush steppe in the valleys.

Nine-anther dalea (Dalea enneandra) Gravelly grasslands slopes on the plains of eastern Montana.

Silky prairie clover (Dalea villosa var. villosa) Loose sand of sand dunes or eroded from sandstone outcrops in eastern Montana.

Scribner’s panic grass (Dichanthelium oligosanthes var. 

scribnerianum)

Open ponderosa pine woodlands of valleys and plains.

White arctic draba (Draba fladnizensis) Rocky, open soil in the alpine zone.

Porsild’s draba (Draba porsildii) Moist, gravelly open soils in the alpine zone.

Entire-leaved avens (Dryas integrifolia) Stony, limestone-derived soil of exposed ridges and plateaus in the alpine zone.
VEGETATION APPENDIX

VEG-8

TABLE VEG-6

STATE OF MONTANA CRITICALLY IMPERILED (S1) PLANT SPECIES WITH POTENTIAL HABITAT IN THE CBNG PLANNING AREA

Common Name (Scientific Name) Habitat

Eaton’s daisy (Erigeron eatonii ssp. eatonii) Open areas in mountains and foothills.

Beautiful fleabane (Erigeron formosissimus var. viscidus) Meadows and forest openings in the montane and subalpine zones.

Smooth buckwheat (Eriogonum salsuginosum) Barren, often bentonitic soil of badlands in the valleys.

Visher’s buckwheat (Eriogonum visheri) Barren, often bentonitic badlands slopes and outwashes in the plains.

Sheared cotton-grass (Eriophorum calllitrix) Wet, organic soil of fens and seep areas in alpine tundra.

Hiker’s gentian (Gentianopsis simplex) Fens, meadows, and seeps, usually in areas of crystalline parent material, in the montane and 

subalpine zones.

Hutchinsia (Hutchinsia procumbens) Vernally moist, alkaline soil of sagebrush steppe in the valley to lower montane zones.

Coville’s rush (Juncus covillei var. covillei) Open, moist to wet, sandy or gravelly soils along valley rivers.

Large-fruited kobresia (Kobresia macrocarpa) Moist tundra, solifluction* slopes, and gravelly lake shores in the alpine zone.

Island koenigia (Koenigia islandica) Wet, open, gravelly soil in seepage areas in the alpine zone.

Lesica’s bladderpod (Lesquerella lesicii) Gravelly, limestone-derived soil of open ridges and slopes among Douglas-fir and mountain 

mahogany woodlands in the montane zone.

Nuttall’s desert parsley (Lomatium nuttallii) Dry, rocky slopes of open pine woodland in the plains.

Desert dandelion (Malacothrix torreyi) Dry, sandy sagebrush steppe in the valley and foothill zones.

Bractless mentzelia (Mentzelia nuda) Sandy or gravelly soil of open hills and roadsides on the plains of eastern Montana

Nama (Nama densum) Sandy soil of sagebrush desert in the valleys.

Blue toadflax (Nuttallanthus texanus) Open, sandy or acid shale soils of grasslands and woodlands on the plains of eastern Montana.

Alpine poppy (Papaver kluanensis) Open, rocky slopes with delayed snowmelt in the alpine zone.

Large flowered beardtongue (Penstemon grandiflorus) Sandy soils of valley plains.

Double bladderpod (Physaria brassicoides) Stony or sandy soil of open grassland slopes on the plains in southeastern Montana.

Woolly twinpod (Physaria didymocarpa var. lanata) Sandy, often calcareous soil of open grassland or shrubland slopes in the plains.

Slender-branched popcorn-flower (Plagiobothrys 

leptocladus)

Dry mud on the shores of ponds in plains and foothills.
VEGETATION APPENDIX

VEG-9

TABLE VEG-6

STATE OF MONTANA CRITICALLY IMPERILED (S1) PLANT SPECIES WITH POTENTIAL HABITAT IN THE CBNG PLANNING AREA

Common Name (Scientific Name) Habitat

Short-leaved bluegrass (Poa curta) Sparsely vegetated soil of Douglas-fir forest floor in the montane zone.

Low arctic cinquefoil (Potentilla hyparctica) Moist turf in the alpine zone.

Platte cinquefoil (Potentilla plattensis) Grasslands and sagebrush steppe in the valley and montane zones in south-central Montana.

One-flowered cinquefoil (Potentilla uniflora) Open, gravelly slopes and ridgetops in the alpine zone.

Bur oak (Quercus macrocarpa) Low, shale-derived hills on the plains.

Arctic buttercup (Ranunculus gelidus) Moist, open soil on tundra and talus slopes in the alpine zone.

Persistent-sepal yellow-cress (Rorippa calycina) Riverbanks and shorelines in the valleys on the plains on the Missouri and Yellowstone Rivers.

Barratt’s willow (Salix barrattiana) Cold, moist soil in the alpine zone.

Yellow marsh saxifrage (Saxifraga hirculus) Wet, organic soil of fen in the alpine zone.

Clasping groundsel (Senecio amplectens) Stony, open soil and talus of slopes in or near the alpine zone.

Shoshonea (Shoshonea pulvinata) Open, exposed limestone outcrops, ridgetops, and canyon rims, in thin rocky soils.

Prairie aster (Solidago ptarmicoides) Open, dry grasslands, often on sandy soil or limestone on the plains of eastern Montana.

Few-flowered goldenrod (Solidago sparsiflora) Sandy soil of grasslands or open woodlands on the plains.

Slender wedgegrass (Sphenopholis intermedia) Wet areas in the valleys or foothills.

Small dropseed (Sporobolus neglectus) Natural and disturbed grasslands.

Fleshy stitchwort (Stellaria crassifolia) Moist or wet meadows, often along streams, in the foothills to alpine zones.

Letterman’s needlegrass (Stipa lettermanii) Limestone talus and dry fescue grassland in the valley and foothill zones in southern Montana.

Poison suckleya (Suckleya suckleyana) Playas and disturbed alkaline soils on the plains.

Nannyberry (Viburnum lentago) Openings in riparian forests on the plains.

S1: At high risk because of extremely limited and/or rapidly declining numbers, range, and/or habitat, thus making it highly vulnerable to extirpation in the 

state.
VEGETATION APPENDIX

VEG-10

TABLE VEG-7

STATE OF MONTANA NOXIOUS WEEDS

Common Name Scientific Name Category

Hoary cress or White top Cardaria draba 1

Diffuse knapweed Centaurea diffusa 1

Spotted knapweed Centaurea maculosa 1

Russian knapweed Centaurea repens 1

Yellow starthistle Centaurea solstitialis 3

Rush skeletonweed Chondrilla juncea 3

Oxeye daisy Chrysanthemum leucanthemum 1

Canada thistle Cirsium arvense 1

Field bindweed Convolvulus arvensis 1

Common crupina Crupina vulgaris 3

Houndstongue Cynoglossum officinale 1

Leafy spurge Euphorbia esula 1

Orange hawkweed Hieracium aurantiacum 2

Yellow-devil hawkweed Hieracium floribundum 2

Kingdevil hawkweed Hieracium piloselloides 2

Meadow hawkweed Hieracium pratense 2

Common St. Johnswort Hypericum perforatum 1

Yellowflag iris Iris pseudacorus 3

Dyer’s woad Isatis tinctoria 2

Perennial pepperweed Lepidium latifolium 2

Dalmatian toadflax Linaria dalmatica 1

Yellow toadflax Linaria vulgaris 1

Purple loosestrife Lythrum salicaria 2

Wandlike loosestrife Lythrum virgatum 2

Eurasian watermilfoil Myriophyllum spicatum 3

Sulfur cinquefoil Potentilla recta 1

Tall buttercup Ranunculus acris 2

Tansy ragwort Senecio jacobaea 2

Tamarisk (Saltcedar) Tamarix spp. 2

Common tansy Tanacetum vulgare 1

Source: The University of Montana – Missoula, Invaders Database System, June 2004.

1 = Noxious weed: currently established and generally widespread in many counties.

2 = Noxious weed: recently introduced and rapidly spreading.

3 = Noxious weeds: not detected in the state or found only in small, scattered, localized infestations.
VEGETATION APPENDIX

VEG-11

TABLE VEG-8

PLANT SPECIES OF CONCERN IN THE PLANNING AREA

Common Name Scientific Name Known to Occur in the 13 Counties

Additional Information

MT BLM USFS

Musk-root Adoxa 

moschatellina

Carbon and Stillwater S2 S S

Lead plant Amorpha 

canescens

Carter and Rosebud SH S

Short-styled 

columbine

Aquilegia 

brevistyla

Sweet Grass S2 S

Daggett rock 

cress

Arabis demissa var 

languida 

Carbon S1 S

Swamp 

milkweed

Asclepias 

incarnata

Carbon S1

Ovalleaf 

milkweed

Asclepias ovalifolia Carter S1 - S

Narrowleaf 

milkweed

Asclepias 

stenophylla

Carter and Rosebud S1 S

Sweetwater 

milkvetch

Astragalus 

aretioides

Big Horn and Carbon S2 S

Barr’s milkvetch Astragalus barrii Big Horn, Carter, Powder River, and 

Rosebud

S2S3 S S

Geyer's 

milkvetch

Astragalus geyeri Carbon and Custer S2 S

Gray's milkvetch Astragalus grayi Carbon S2 S

Wind River 

milkvetch

Astragalus 

oreganus

Carbon S1 S

Obscure eveningprimroseCamissonia andina Carbon S2 S

Small camissonia Camissonia 

parvula

Carbon S1 S

Pregnant sedge Carex gravida var. 

gravida

Big Horn, Powder River, and Rosebud S1

Toothed 

Scandinavian 

sedge

Carex norvegica 

ssp. inserrulata

Carbon and Stillwater S1

Birchleaf 

mountainmahogany

Cercocarpus 

montanus var.

glaber

Treasure S1S2 -

Smooth 

goosefoot

Chenopodium 

subglabrum

Carter, Custer, and Powder River S1 -

Yellow bee plant Cleome lutea Big Horn and Carbon S1 S
VEGETATION APPENDIX

VEG-12

TABLE VEG-8

PLANT SPECIES OF CONCERN IN THE PLANNING AREA

Common Name Scientific Name Known to Occur in the 13 Counties

Additional Information

MT BLM USFS

Miner’s candle Cryptantha

scoparia

Carbon S1 S

Schweinitz' 

flatsedge

Cyperus 

schweinitzii

Carter, Custer, and Powder River S2 S

Small yellow 

lady's-slipper

Cypripedium 

parviflorum

Stillwater and Sweet Grass S2S3 S S

Nine-anther 

dalea

Dalea enneandra Custer S1 -

Silky prairie 

clover

Dalea villosa var. 

villosa

Carter S1 -

Scribner’s panic 

grass

Dichanthelium 

oligosanthes var. 

scribnerianum

Powder River S1 S

White arctic 

draba

Draba fladnizensis Carbon and Stillwater S1

Porsild’s draba Draba porsildii Carbon S1

Entire-leaved 

avens

Dryas integifolia Golden Valley S1

Beaked spikerush Eleocharis 

rostellata

Carbon and Sweet Grass S2 S

Long sheath 

waterweed

Elodea 

longivaginata

Stillwater S2 S

Giant helleborine Epipactis gigantea Carbon S2 S

Eaton’s daisy Erigeron eatonii 

ssp. eatonii

Sweet Grass S1

Beautiful 

fleabane

Erigeron 

formosissimus var.

viscidus

Carbon S1 -

Smooth 

buckwheat

Eriogonum 

salsuginosum 

Carbon S1 S

Visher’s 

buckwheat

Eriogonum visheri Carter S1 S

Sheathed cottongrassEriophorum 

calllitrix

Carbon S1

Hiker’s gentian Gentianopsis 

simplex

Carbon S1 - S
VEGETATION APPENDIX

VEG-13

TABLE VEG-8

PLANT SPECIES OF CONCERN IN THE PLANNING AREA

Common Name Scientific Name Known to Occur in the 13 Counties

Additional Information

MT BLM USFS

Northern 

rattlesnakeplantain

Goodyera repens Wheatland S2S3 S

Bractless hedgehyssopGratiola 

ebracteata

Yellowstone S1

Spiny hopsage Grayia spinosa Carbon S2 S

Beartooth largeflowered 

goldenweed

Haplopappus 

carthamoides var.

subsquarrosus

Carbon S2 S S

Hutchinsia Hutchinsia 

procumbens

Carbon S1 S

Coville's rush Juncus covillei var. 

covillei

Sweet Grass S1

Large-fruited 

kobresia

Kobresia 

macrocarpa

Carbon S1

Island koenigia Koenigia islandica Carbon S1

Leptodactylon Leptodactylon 

caespitosum

Carbon S2 S

Lesica’s 

bladderpod

Lesquerella lesicii Carbon S1 S

Nuttall’s desert 

parsley

Lomatium nuttallii Big Horn and Rosebud S1 S

Desert dandelion Malacothrix torreyi Carbon S1 S

White-bract 

stickleaf

Mentzelia montana Custer SH S

Bractless

mentzelia

Mentzelia nuda Custer, Powder River, and Rosebud S1 S

Dwarf mentzelia Mentzelia pumila Carbon S2 S

Nama Nama densum Carbon S1 S

Blue toadflax Nuttallanthus 

texanus

Carter S1 -

Alpine poppy Papaver kluanensis Carbon and Sweet Grass S1

Narrowleaf 

penstemon

Penstemon 

angustifolius

Carter S2 S

Large flowered 

beardtongue

Penstemon 

grandiflorus

Custer S1

Plains phlox Phlox andicola Carter, Powder River, and Rosebud S2 S
VEGETATION APPENDIX

VEG-14

TABLE VEG-8

PLANT SPECIES OF CONCERN IN THE PLANNING AREA

Common Name Scientific Name Known to Occur in the 13 Counties

Additional Information

MT BLM USFS

Double 

bladderpod

Physaria 

brassicoides

Carter and Powder River S2 S

Woolly twinpod Physaria 

didymocarpa var.

lanata

Big Horn and Rosebud S1 S

Slender-branched 

popcorn-flower

Plagiobothrys 

leptocladus

Custer S1 S

Short-leaved 

bluegrass

Poa curta Carbon S1 S

Low arctic 

cinquefoil

Potentilla 

hyparctica

Carbon S1

Platte cinquefoil Potentilla 

plattensis

Carbon S1 S

One-flowered 

cinquefoil

Potentilla uniflora Carbon S1

Mealy primrose Primula incana Carbon S2 S S

Bur oak Quercus 

macrocarpa

Carter S1 S

Arctic buttercup Ranunculus gelidus Stillwater S1

Persistent-sepal 

yellow-cress

Rorippa calycina Big Horn, Custer, Rosebud, Treasure, and 

Yellowstone

S1 S

Barratt’s willow Salix barrattiana Carbon S1 S

Yellow marsh 

saxifrage

Saxifraga hirculus Carbon S1

Clasping 

groundsel

Senecio amplectens 

var. holmii

Carbon S1

Shoshonea Shoshonea 

pulvinata

Carbon S1 S S

Prairie aster Solidago 

ptarmicoides

Carter S1

Few-flowered 

goldenrod

Solidago 

sparsiflora

Stillwater S1 S

Slender 

wedgegrass

Sphenopholis 

intermedia

Big Horn S1 -

Small dropseed Sporobolus 

neglectus

Wheatland S1

Fleshy stitchwort Stellaria crassifolia Carbon S1 -
VEGETATION APPENDIX

VEG-15

TABLE VEG-8

PLANT SPECIES OF CONCERN IN THE PLANNING AREA

Common Name Scientific Name Known to Occur in the 13 Counties

Additional Information

MT BLM USFS

Letterman’s 

needlegrass

Stipa lettermanii Big Horn and Carbon S1

Poison suckleya Suckleya 

suckleyana

Musselshell S1

Wyoming 

sullivantia

Sullivantia 

hapemanii

Big Horn and Carbon S2 S

Small-flowered 

pennycress

Thlaspi 

parviflorum

Carbon S2 S

Nannyberry Viburnum lentago Big Horn S1

S = sensitive

S1: At high risk because of extremely limited and/or rapidly declining numbers, range and/or habitat, making it highly vulnerable to extirpation in 

the state.

S2: At risk because of very limited and/or declining numbers, range and/or habitat, making it vulnerable to extirpation in the state.

S3: At risk because of very limited and/or declining numbers, range and/or habitat, making it vulnerable to extirpation in the state.

SH: Possibly extinct - species known from only historical occurrences, but may nevertheless still be extant; further searching is needed.