More info for the terms: codominant, cover, forb, forbs, heath, presence, shrubs
Low sagebrush species cover approximately 28 million acres (11.2 million ha) in the western
United States [13]. Recognized habitat types include gray low sagebrush/bluebunch wheatgrass
(Pseudoroegneria spicata), gray low sagebrush/Idaho
fescue (Festuca idahoensis), gray
low sagebrush/Thurber's needlegrass (Achnatherum thurberianum), gray low
sagebrush/bitterbrush (Purshia tridentata)/bluebunch wheatgrass, hotsprings sagebrush/Idaho fescue,
alkali
sagebrush/bluebunch wheatgrass, and alkali sagebrush/Idaho fescue [20]. Lahontan sagebrush
grows with many of the same associates; Lahontan sagebrush is an ecosystem
dominant on about 500,000
acres (200,000 ha) [116].
Washington: In eastern Washington low sagebrush grows with stiff sagebrush (A.
rigida) and mountain big sagebrush (A. t. ssp. vaseyana) with
an understory of elk sedge (Carex geyeri),
Idaho fescue, Sandberg bluegrass (Poa secunda), and bluebunch wheatgrass
[30]. Low sagebrush is not particularly common and, for the most part,
is restricted to Chelan, Kittias, and Yakima
counties [13].
Oregon: On the Deschutes, Winema, and Fremont National Forests, low sagebrush (with 5-15% canopy cover) grows with Idaho fescue (2-16%
cover) and bluebunch wheatgrass, Sandberg bluegrass, bottlebrush squirreltail (Elymus
elymoides), and low
pussytoes (Antennaria dimorpha). Such habitats in
"poor condition" are characterized by increasing rabbitbrush (Chrysothamnus spp.) and cheatgrass
(Bromus tectorum); on mesic
sites antelope bitterbrush, California oatgrass
(Danthonia californica), and prairie Junegrass (Koeleria
macrantha) are present [33,51,110]. Forbs present in the communities include rosy pussytoes (Antennaria
microphylla), fleabane (Erigeron spp.), rockcress (Arabis spp.), and
milkvetch (Astragalus
spp.). On sites slightly drier than those occupied by ponderosa pine (Pinus
ponderosa) forests, low sagebrush and antelope bitterbrush are dominant with
green rabbitbrush (Chrysothamnus viscidiflorus) and rubber
rabbitbrush (C. nauseosus) as minor shrubs where soils
are deeper. The most prominent grass is Thurber's needlegrass. Low sagebrush is an occasional component of silver sagebrush (A. cana)/mat
muhly (Muhlenbergia richardsonis) communities [33]. Other
associates of low sagebrush in eastern Oregon are stiff sagebrush, snowberry (Symphoricarpos spp.),
wax currant (Ribes cereum), and Saskatoon serviceberry (Amelanchier
alnifolia) [45].
California: On the Modoc Plateau of northeastern California, common
understory associates in low sagebrush stands
are Idaho fescue, bitterbrush (Purshia spp.), bluebunch wheatgrass,
Thurber's needlegrass, prairie Junegrass, phlox (Phlox spp.), pussytoes (Antennaria
spp.), fleabane, blue-eyed Mary (Collinsia spp.), Ross' sedge
(Carex rossii),
and rushes (Juncus spp.). Shrubs frequently associated are western juniper (Juniperus occidentalis), green
rabbitbrush, gray horsebrush (Tetradymia canescens), and longflower snowberry (S.
longiflorus). Cheatgrass, garlic mustard (Alliaria petiolata), and
medusahead (Taeniatherum caput-medusae) are prominent weedy species after grazing; historically
bottlebrush squirreltail and/or Sandberg bluegrass had greater canopy cover [9].
Low sagebrush is more common in
western juniper stands than in pinyon (Pinus spp.)/juniper (Juniperus spp.)
stands; big sagebrush is much more frequently found in pinyon-juniper stands [22]. In the White Mountains of eastern California in Rocky Mountain
bristlecone pine (Pinus aristata), limber pine (P. flexilis), and
quaking aspen (Populus tremuloides) stands with
discontinuous sparse cover, low sagebrush grows with big sagebrush, green
rabbitbrush, curlleaf mountain-mahogany (Cercocarpus ledifolius),
littleleaf mountain-mahogany (C. intricatus), fernbush (Chamaebatiaria millefolium),
oceanspray (Holodiscus discolor), and desert gooseberry (Ribes velutinum).
Grasses present include are prairie Junegrass, bottlebrush squirreltail, mat
muhly, and timblerline bluegrass (Poa glauca var. rupicola) [68].
Utah: Low
sagebrush grows in Utah in Box Elder, Cache, Millard, Rich,
Salt Lake, Summit, and Toole counties in Colorado pinyon (Pinus edulis)/juniper, mountain brush,
sagebrush, and, to a lesser extent, in openings in white fir (Abies concolor),
quaking aspen, and Engelmann spruce (Picea engelmannii)-white fir communities. Alkali sagebrush is found in sagebrush
grassland communities in Rich and Summit
counties [113]. In the interior ponderosa pine (P. p. var. scopulorum)/black
sagebrush habitat type, trees present are limber pine (in
Utah only), Colorado pinyon, and Rocky Mountain juniper (Juniperus scopulorum).
Dominant shrubs include low sagebrush, green rabbitbrush, Gambel oak (Quercus
gambelii), gray horsebrush, and blue grama (Bouteloua
gracilis) [1]. In Uintah County of northeastern Utah, low sagebrush grows in
Colorado pinyon/Utah juniper (Juniperus osteosperma)
communities with big sagebrush, fourwing saltbrush (Atriplex canescens),
shadscale (Atriplex confertifolia), true mountain-mahogany (Cercocarpus
montanus), birchleaf mountain-mahogany (Cercocarpus betuloides),
and ephedra (Ephedra spp.). Important grasses are purple threeawn (Aristida
purpurea), saltgrass (Distichlis spicata), Indian
ricegrass (Achnatherum hymenoides), Sandberg bluegrass,
needle-and-thread grass (Hesperostipa comata), bottlebrush
squirreltail; forbs include Fendler's sandwort (Arenaria fendleri),
rose heath (Chaetopappa ericoides), thickstem wild cabbage (Caulanthus
crassicaulis), cryptantha (Cryptantha spp.), Fendler's
springparsley (Cymopterus acaulis var. fendleri),
prickly-pear (Opuntia spp.), and others [6].
Montana: Low sagebrush is found only in southwestern Montana. Gray low sagebrush is in Beaverhead, Madison, and Deer Lodge counties
[13,79]. Common associates include slender wheatgrass (Elymus
trachycaulus) and
Idaho fescue [79]. Alkali sagebrush is present in only a few isolated
stands in Beaverhead and Madison counties [17,79]. Alkali sagebrush occurs with Idaho fescue, western wheatgrasss
(Pascopyrum smithii), thickspike wheatgrass (Elymus lanceolatus),
bluebunch
wheatgrass, and alkali cordgrass (Spartina gracilis) [79].
Idaho: The gray low sagebrush/bluebunch wheatgrass habitat type supports bluebunch
wheatgrass, Sandberg bluegrass, bottlebrush squirreltail, Hood's phlox (Phlox
hoodii), tapertip hawksbeard (Crepis acuminata)
and prairie Junegrass [48,94]. The gray low sagebrush/Idaho fescue type is
widespread in western Idaho in the same elevation zone; forb associates are
phlox, rosy pussytoes, tapertip hawksbeard, lambstongue ragwort (Senecio integerrimus), and Hooker balsamroot (Balsamorhiza
hookeri); bluebunch wheatgrass is abundant on some sites and absent
on others. The gray low sagebrush/Sandberg bluegrass habitat type
occurs where soils are too shallow to support Idaho fescue or bluebunch
wheatgrass. In this type, Sandberg bluegrass and gray low sagebrush have increased with grazing
pressure and species diversity has been reduced. In the Dautrich
Memorial Desert Preserve in southeastern Idaho, low sagebrush sometimes grows with
big sagebrush, fourwing saltbrush, shadscale, littleleaf horsebrush (Tetradymia glabrata),
grayball sage (Salvia dorrii), and basin wildrye (Leymus cinereus) [50]. The
alkali sagebrush/Idaho fescue type occurs on and near the Owyhee Plateau; associated grasses are bluebunch wheatgrass
and Thurber's needlegrass (with variable presence and cover) and Sandberg
bluegrass. Forbs are small bluebells (Mertensia longiflora),
narrowleaf pussytoes (Antennaria
stenophylla), alpine ionactis (Ionactis alpina), tapertip
onion (Allium accuminatum), and Holboell's rockcress (Arabis holboellii) [48].
Hotsprings sagebrush is only known in Custer County, Idaho [13]. The hotsprings
sagebrush/Idaho fescue habitat type occupies glacial outwashes and ridges with
thin soil; bluebunch wheatgrass is sometimes present. In some areas grazing
pressure has caused Idaho fescue to be replaced by Letterman needlegrass (Achnatherum
lettermanii) [48]. Other associates include Sandberg bluegrass, bottlebrush
squirreltail, fleabane, rosy pussytoes, Hood's phlox, and snowline springparsley (Cymopterus
nivalis) [94].
Wyoming: Gray low sagebrush grows in Lincoln and Teton counties, and hotsprings
sagebrush grows in Lincoln and Teton counties and Yellowstone National Park [13]. Alkali sagebrush is in Carbon, Hot Springs, Lincoln, Sublette, Teton
and Uinta counties [17]. Beetle [16] estimated that in Wyoming gray low
sagebrush covers about 2,000 square miles (510,000 ha) and alkali sagebrush covers the same;
hotspring sagebrush covers about 100 square miles (26,000 ha). Gray low sagebrush and alkali
sagebrush are confined primarily to
the western part of the state; hotsprings sagebrush is in the northwestern part. Common understory grasses are western wheatgrass, thickspike
wheatgrass, Idaho fescue, prairie Junegrass, Cusick's bluegrass (Poa cusickii),
mutton grass (Poa fendleriana), and
Sandberg bluegrass [105].
Nevada: Alkali sagebrush is present in Elko and Humboldt counties
[13,17,124]. The
alkali sagebrush/Idaho fescue habitat type is common in Elko County; the type is
very similar to the composition of the
gray low sagebrush/Idaho
fescue type described above, but Thurber's needlegrass is generally more prominent
[124].
Gray low sagebrush is best represented in northern Nevada; in
southern Nevada this variety is a component of singleleaf pinyon (Pinus monophylla)/Utah
juniper stands [124]. In the gray low sagebrush/Sandberg bluegrass
habitat type species present include fleabane,
phlox, bitterroot (Lewisia rediviva), milkvetch, Idaho fescue, and curlleaf mountain-mahogany. In singleleaf
pinyon/Utah juniper communities low sagebrush grows with
big sagebrush, green rabbitbrush, antelope bitterbrush, cheatgrass, bottlebrush
squirreltail, California brome (Bromus carinatus), Sandberg
bluegrass, bushy bird's beak (Cordylanthus ramosus), tapertip
onion, longleaf phlox (Phlox longifolia), sego lily (Calochortus nuttallii),
largeflower hawksbeard (Crepis occidentalis), and pinyon
groundsmoke (Gayophytum ramosissimum)
[19].
In the Ruby Mountains gray low sagebrush communities typical species
are
Idaho fescue, bottlebrush squirreltail, green rabbitbrush, Sandberg
bluegrass, fleabane, granite prickly phlox (Leptodactylon
pungens), spike fescue (Leucopoa kingii), lupines (Lupinus
spp.), Wyoming Indian paintbrush (Castilleja linariifolia),
colddesert phlox (Phlox stansburyii), and
pussytoes [67].
The gray low sagebrush/Thurber's needlegrass habitat type is common in northwestern
Nevada; subdominant grasses are Sandberg bluegrass,
bottlebrush squirreltail, and Idaho fescue. Forbs present are fleabane,
Hood's phlox, alpine ionactus, and woollypod milkvetch (Astragalus purshii) [124].
New Mexico: Gray low sagebrush grows on dry plains, mountain
slopes, and ridges in northwestern and west-central New Mexico [69]. With Utah juniper frequently codominant, low sagebrush grows with big sagebrush,
fourwing saltbush, Stansbury cliffrose (Purshia mexicana var. stansburiana),
broom snakeweed (Gutierrezia sarothrae), prickly-pear, and pingue
hymenoxys (Hymenoxys
richardsonii). Common grasses are blue grama, hairy grama (Bouteloua
hirsuta), sideoats grama (B. curtipendula), galleta (Pleuraphis
jamesii), threeawn (Aristida spp.), western wheatgrass,
bottlebrush squirreltail, and Indian ricegrass [63].
Colorado: In the White River-Arapaho National Forest the low sagebrush/arrowleaf
balsamroot (Balsamorhiza sagittata) habitat type occurs on warm aspects; associated shrubs are Utah
serviceberry (Amelanchier utahensis), longflower rabbitbrush (Chrysothamnus
depressus), and mountain snowberry (Symphoricarpos oreophilus). Prominent grasses include prairie
Junegrass, mutton grass, Sandberg bluegrass, and bottlebrush squirreltail, and
forbs of importance are pale agoseris (Agoseris glauca), Geyer's
onion (Allium geyeri), Gunnison's mariposa lily (Calochortus gunnisonii),
largeflower hawksbeard, Gray's biscuitroot (Lomatium grayi), and
lambstongue ragwort [46].
Alkali sagebrush grows in Garfield, Jackson, Routt, Moffat, and Rio
Blanco counties [13]. The alkali sagebrush/Sandberg bluegrass habitat type
occurs in central Colorado.
Grasses present (in
descending importance) are bottlebrush squirreltail, mutton grass (Poa fendleriana),
bluebunch wheatgrass, western wheatgrass, pine needlegrass (Achnatherum pinetorum),
needle-and-thread grass, prairie Junegrass, cheatgrass, and
basin wildrye [103]. Other important shrubs are green rabbitbrush,
mountain snowberry, fringed sagebrush
(Artemisia frigida), winterfat (Krascheninnikovia lanata),
broom snakeweed, and Vasey's rabbitbrush (Chrysothamnus vaseyi). Forbs present are phlox,
mat penstemon (Penstemon caespitosus), and fleabane [102].
Classifications describing plant communities in which low sagebrush is a
dominant species are as follows:
California: [9]
Colorado: [46,103]
Idaho: [48]
Montana: [81]
Nevada: [19,53,124]
New Mexico: [63]
Oregon: [110]
Wyoming: [105]