Natural Resources
Conservation Service
-
Search
Major Land Resource Area or ecological site by name and/or ID.
PreviousSectionsNextGeneral information
Draft. A draft ecological site description is either incomplete or has not undergone quality control and quality assurance review.
Classification relationships
Holland, R.F. 1986. Preliminary descriptions of the terrestrial natural communities of California. Unpublished report. State of California, The Resources Agency, Department of Fish and Game, Natural Heritage Division, Sacramento, CA. (Updated September 2003). Element Code: Big Sagebrush 35.110.02.
Sawyer, J.O. and T. Keeler-Wolf. 1995. A Manual of California Vegetation. California Native Plant Society, Sacramento, CA. Big Sagebrush Series.
Table 1. Dominant plant species
Tree Not specified
Shrub (1) Artemisia tridentata ssp. vaseyana
Herbaceous (1) Festuca idahoensis
(2) Pseudoroegneria spicata ssp. spicataPhysiographic features
This site occurs on mountain slopes. Slopes range from 15 to 50 percent. Elevations range from 5000 to 6400 feet.
Table 2. Representative physiographic features
Landforms (1) Mountain slope
Elevation 5000 – 6400 ft Slope 15 – 50 % Aspect Aspect is not a significant factor Climatic features
The climate of this site is temperate, characterized by warm, dry summers and cold, moist winters. The area's precipitation comes mostly from winter Pacific cyclonic storms, with a very slight summer monsoonal season that is erratic but can be locally significant. Average annual precipitation ranges from 16 to 30 inches with most occurring during the winter months. Approximately half the precipitation falls as snow; half as rain. The mean annual air temperature is 41 to 45 degrees F. The average growing season is about 50 to 80 days.
Table 3 Representative climatic features
Frost-free period (average) 80 days Freeze-free period (average) 0 days Precipitation total (average) 30 in BarLineFigure 1. Monthly precipitation range
BarLineFigure 2. Monthly average minimum and maximum temperature
">Influencing water features
There are no influencing water features associated with this site.
Soil features
This site occurs on shallow, well drained soils that formed in volcanic ash and colluvium over residuum derived from andesite, tuff, or glassy tuff-breccia. These soils are usually moist during winter, spring, and early summer and dry later in summer and fall. These soils have high amounts of vitric volcanic ash and glass throughout the soil profile which enchances the water holding capacity of these soils. Soil series associated with this site include Crazybird and Sesdah.
Table 4. Representative soil features
Parent material (1) Volcanic ash – andesite
Surface texture (1) Gravelly loam
(2) Very gravelly sandy loam
Family particle size (1) Loamy
Drainage class Well drained Permeability class Moderate Soil depth 14 – 20 in Surface fragment cover <=3" 15 – 50 % Surface fragment cover >3" 7 – 11 % Available water capacity
(0-40in)2.4 – 2.9 in Calcium carbonate equivalent
(0-40in)Not specified Electrical conductivity
(0-40in)Not specified Sodium adsorption ratio
(0-40in)Not specified Soil reaction (1:1 water)
(0-40in)6.1 – 7.3 Subsurface fragment volume <=3"
(Depth not specified)15 – 65 % Subsurface fragment volume >3"
(Depth not specified)5 – 20 % Ecological dynamics
Where management results in abusive grazing use by livestock, mountain big sagebrush will increase at the expense of Idaho fescue and bluebunch wheatgrass. Moderate to heavy sheep use of this site will decrease abundance of Idaho fescue, needlegrass and bluegrasses. Heavy, early season, cattle or horse use will decrease bluebunch wheatgrass composition in the community. Cheatgrass and thistle are plant species most likely to invade this site.
Fire effects:
Presettlement fire return intervals in mountain big sagebrush communities varied from 15-25 years. Mountain big sagebrush is highly susceptible to injury from fire. Plants are readily killed in all seasons, even light severity fires. Mountain big sagebrush plants top-killed by fire will not resprout.
Burning bluebunch wheatgrass may remove most of the aboveground biomass but does not usually result in plant mortality. Bluebunch wheatgrass is generally favored by burning. Burning stimulates flowering and seed production. However, season of burning affects mortality.
Idaho fescue grows in a dense, fine-leaved tuft. Fires tend to burn within the accumulated fine leaves at the base of the plant and may produce temperatures sufficient to kill some of the root crown. Mature Idaho fescue plants are commonly reported to be severely damaged by fire in all seasons.
Fire effects:
Presettlement fire return intervals in mountain big sagebrush communities varied from 15-25 years. Mountain big sagebrush is highly susceptible to injury from fire. Plants are readily killed in all seasons, even light severity fires. Mountain big sagebrush plants top-killed by fire will not resprout.
Burning bluebunch wheatgrass may remove most of the aboveground biomass but does not usually result in plant mortality. Bluebunch wheatgrass is generally favored by burning. Burning stimulates flowering and seed production. However, season of burning affects mortality. Idaho fescue grows in a dense, fine-leaved tuft. Fires tend to burn within the accumulated fine leaves at the base of the plant and may produce temperatures sufficient to kill some of the root crown. Mature Idaho fescue plants are commonly reported to be severely damaged by fire in all seasons.
State and transition model
More interactive model formats are also available. View Interactive Models
Click on state and transition labels to scroll to the respective textEcosystem states
State 1 submodel, plant communities
State 1
Reference StateCommunity 1.1
Reference Plant Community
Figure 3. Ashy Loamy Slope
The reference plant community is dominated by bluebunch wheatgrass, Idaho fescue and mountain big sagebrush. Potential vegetative composition is about 50% grasses, 20% forbs, 10% mosses and 20% shrubs.
Figure 4. Annual production by plant type (representative values) or group (midpoint values)
Table 5. Annual production by plant type
Plant type Low
(lb/acre)Representative value
(lb/acre)High
(lb/acre)Grass/Grasslike 250 350 500 Shrub/Vine 100 140 200 Forb 100 140 200 Moss 50 70 100 Total 500 700 1000 Additional community tables
Table 6. Community 1.1 plant community composition
Group Common name Symbol Scientific name Annual production () Foliar cover (%) Grass/Grasslike1 Primary Perennial Grasses 259–476 Idaho fescue FEID Festuca idahoensis 210–315 – bluebunch wheatgrass PSSPS Pseudoroegneria spicata ssp. spicata 35–105 – Sandberg bluegrass POSE Poa secunda 14–56 – 2 Secondary Perennial Grasses 16–56 needlegrass ACHNA Achnatherum 4–14 – mountain brome BRMA4 Bromus marginatus 4–14 – squirreltail ELEL5 Elymus elymoides 4–14 – prairie Junegrass KOMA Koeleria macrantha 4–14 – Forb3 Perennial Forbs 40–70 common yarrow ACMI2 Achillea millefolium 4–7 – rockcress ARABI2 Arabis 4–7 – arrowleaf balsamroot BASA3 Balsamorhiza sagittata 4–7 – sagebrush mariposa lily CAMAM9 Calochortus macrocarpus var. macrocarpus 4–7 – castilla CASTI Castilla 4–7 – tapertip hawksbeard CRAC2 Crepis acuminata 4–7 – prickly hawkweed HIHO Hieracium horridum 4–7 – lupine LUPIN Lupinus 4–7 – cold-desert phlox PHST11 Phlox stansburyi 4–7 – brightwhite PREX Prenanthella exigua 4–7 – 4 Annual Forbs 4–21 grand collomia COGR4 Collomia grandiflora 4–21 – Moss5 Moss 35–105 sphagnum SPHAG2 Sphagnum 35–105 – Shrub/Vine6 Primary Shrubs 70–140 mountain big sagebrush ARTRV Artemisia tridentata ssp. vaseyana 70–140 – 7 Secondary Shrubs 35–70 Utah serviceberry AMUT Amelanchier utahensis 7–14 – curl-leaf mountain mahogany CELE3 Cercocarpus ledifolius 7–14 – yellow rabbitbrush CHVI8 Chrysothamnus viscidiflorus 7–14 – antelope bitterbrush PUTR2 Purshia tridentata 7–14 – Interpretations
Animal community
Livestock Interpretations:
This site is suited for cattle and sheep grazing during the spring, summer and fall. Attentive grazing management is required due to steep slopes and erosive soil surface conditions. Grazing management should be keyed to Idaho fescue and bluebunch wheatgrass production. Big sagebrush is eaten by domestic sheep and cattle, but has long been considered to be of low palatability to domestic livestock, a competitor with more desirable species, and a physical impediment to grazing.
Stocking rates vary over time depending upon season of use, climate variations, site, and previous and current management goals. A safe starting stocking rate is an estimated stocking rate that is fine tuned by the client by adaptive management through the year and from year to year.
Wildlife Interpretations:
Big sagebrush is highly preferred and nutritious winter forage for mule deer. Sage grouse are also highly dependent on big sagebrush for both food and cover. Bluebunch wheatgrass and Idaho fescue provides important forage for many types of domestic livestock and several wildlife species.Hydrological functions
Runoff is medium to high.
Other products
Native peoples used big sagebrush leaves and branches for medicinal teas, and the leaves as a fumigant. Bark was woven into mats, bags and clothing.
Other information
Mountain big sagebrush has potential for range restoration and soil stabilization.
Supporting information
Type locality
Location 1: Modoc County, CA Township/Range/Section T42N R16E S31 Latitude 41° 28′ 13″ Longitude 120° 11′ 32″ General legal description On the Modoc National Forest in the Warner Mountains Other references
Fire Effects Information System [Online]. http://www.fs.fed.us/feis
Miles, S.R. and C.B. Goudey. 1997. Ecological Subregions of California Section and Subsection Descriptions. United States Department of Agriculture Forest Service, Pacific Southwest Region R5-EM-TP-005. Subsection M261Gf-Warner Mountains.Contributors
P.NOVAK-ECHENIQUE
Rangeland health reference sheet
Interpreting Indicators of Rangeland Health is a qualitative assessment protocol used to determine ecosystem condition based on benchmark characteristics described in the Reference Sheet. A suite of 17 (or more) indicators are typically considered in an assessment. The ecological site(s) representative of an assessment location must be known prior to applying the protocol and must be verified based on soils and climate. Current plant community cannot be used to identify the ecological site.
Author(s)/participant(s) Contact for lead author Date Approved by Approval date Composition (Indicators 10 and 12) based on Annual Production Indicators
-
Number and extent of rills:
-
Presence of water flow patterns:
-
Number and height of erosional pedestals or terracettes:
-
Bare ground from Ecological Site Description or other studies (rock, litter, lichen, moss, plant canopy are not bare ground):
-
Number of gullies and erosion associated with gullies:
-
Extent of wind scoured, blowouts and/or depositional areas:
-
Amount of litter movement (describe size and distance expected to travel):
-
Soil surface (top few mm) resistance to erosion (stability values are averages - most sites will show a range of values):
-
Soil surface structure and SOM content (include type of structure and A-horizon color and thickness):
-
Effect of community phase composition (relative proportion of different functional groups) and spatial distribution on infiltration and runoff:
-
Presence and thickness of compaction layer (usually none; describe soil profile features which may be mistaken for compaction on this site):
-
Functional/Structural Groups (list in order of descending dominance by above-ground annual-production or live foliar cover using symbols: >>, >, = to indicate much greater than, greater than, and equal to):
Dominant:
Sub-dominant:
Other:
Additional:
-
Amount of plant mortality and decadence (include which functional groups are expected to show mortality or decadence):
-
Average percent litter cover (%) and depth ( in):
-
Expected annual annual-production (this is TOTAL above-ground annual-production, not just forage annual-production):
-
Potential invasive (including noxious) species (native and non-native). List species which BOTH characterize degraded states and have the potential to become a dominant or co-dominant species on the ecological site if their future establishment and growth is not actively controlled by management interventions. Species that become dominant for only one to several years (e.g., short-term response to drought or wildfire) are not invasive plants. Note that unlike other indicators, we are describing what is NOT expected in the reference state for the ecological site:
-
Perennial plant reproductive capability:
Print Options
Sections
Font
AAAAOther
PrintThe Ecosystem Dynamics Interpretive Tool is an information system framework developed by the USDA-ARS Jornada Experimental Range, USDA Natural Resources Conservation Service, and New Mexico State University.
Accessibility statement
