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Draft. A draft ecological site description is either incomplete or has not undergone quality control and quality assurance review.
Table 1. Dominant plant species
Tree (1) Abies magnifica
(2) Pinus contortaShrub (1) Artemisia tridentata ssp. vaseyana
Herbaceous (1) Bromus marginatus
(2) Achnatherum occidentale ssp. occidentalePhysiographic features
This forest site typically occurs on high elevation mountains on middle to upper sideslopes. This site occurs on all aspects but is most common on northeast and northwest facing slopes. These sites characteristically lie above 7500 feet. Slopes range from 8 to 50 percent.
Table 2. Representative physiographic features
Landforms (1) Moraine
(2) Mountain slope
Elevation 7500 – 11000 ft Slope 8 – 50 % Aspect NE, NW Climatic features
The climate associated with this site is subhumid with cool, dry summers and cold, wet winters. Average annual precipitation is 30 to 55 inches. Mean annual air temperature is 35 to 40 degrees F. The average growing season is 30 to 60 days.
Table 3 Representative climatic features
Frost-free period (average) 60 days Freeze-free period (average) 0 days Precipitation total (average) 60 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
The soils associated with this site are moderately deep to very deep and are well drained to somewhat excessively drained. They are formed in colluvium from granitic, volcanic, or metamorphic rock sources. The soils typically have an umbric epipedon and a cambic horizon. Runoff is low to very high and permeability is rapid to moderately rapid. The soil moisture control section is usually moist from late fall, winter, and spring, and dry from July through September. Soils correlated to this site include Florand, Forsell, Hargran, Klauspeak, and Stumpatil.
Table 4. Representative soil features
Surface texture (1) Medium gravelly sandy loam
(2) Very gravelly coarse sandy loam
(3) Gravelly loamy sand
Family particle size (1) Loamy
Drainage class Somewhat poorly drained to somewhat excessively drained Permeability class Moderate to rapid Soil depth 40 – 80 in Surface fragment cover <=3" 15 – 40 % Surface fragment cover >3" 1 – 29 % Available water capacity
(0-40in)2.4 – 4.3 in Electrical conductivity
(0-40in)Not specified Sodium adsorption ratio
(0-40in)Not specified Soil reaction (1:1 water)
(0-40in)4.5 – 6 Subsurface fragment volume <=3"
(Depth not specified)17 – 41 % Subsurface fragment volume >3"
(Depth not specified)2 – 25 % Ecological dynamics
California red fir is a native, long-lived conifer that ranges between 66 and 198 feet (20-60 m) in height.California red fir grows best in areas with cold, wet winters and warm,
dry summers. The growing season is short, with snow often on the ground in July. Annual precipitation ranges from 33 to 64 inches (820-1,600 mm), most of which occurs between October and March as snow. Snowpack is usually between 8 and 13 feet.
California red fir will eventually become the climax species under a closed canopy of lodgepole pine. California red fir establishes well in openings and after disturbances and is moderately shade tolerant.
Fire Ecology:
Fire has an important role in Sierra Nevada conifer forests, particularly in the successional relationship between California red fir and lodgepole pine. Fire creates canopy openings by killing mature lodgepole pine and some mature California red fir. Where lodgepole pine occurs under a California red fir canopy, it is eventually succeeded by California red fir. The estimated fire frequency ranges from 10 to 65 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.
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 Plant CommunityCommunity 1.1
Reference Plant CommunityThe reference plant community is characterized by an overstory canopy of 30 to 45 percent. The site is dominated by red fir and lodgepole pine. Western white pine, limber pine, and mountain hemlock may also occur in the overstory. Understory is dominated by mountain big sagebrush, currant, and snowberry. Mountain brome, western needlegrass, Ross' sedge and Bolander's bluegrass are the most prevalent understory grass and grass-like plants. Lupine, rockcress, coyote mint, mountain sweetroot, mule's ear wyethia, and white flowered hawkweed are common understory forbs.
An overstory canopy of 30 to 45 percent is assumed to be representative of tree dominance on this site in the pristine environment.Forest overstory.MATURE WOODLAND: The visual aspect and vegetal structure are dominated by red fir and lodgepole pine that have reached or are near maximal heights for the site. Tree canopy cover ranges from 30 to about 45 percent. This stage of community development is assumed to be representative of this woodland site in the pristine environment.<br /> <br />
Forest understory. Understory vegetative composition is about 45 percent grasses and grass-like plants, 20 percent forbs and 35 percent shrubs and young trees whent he average overstory canopy is medium. Average understory production ranges from 400 to 700 pounds per acre.
Figure 3. 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 158 210 245 Forb 112 150 175 Tree 90 120 140 Shrub/Vine 90 120 140 Total 450 600 700 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/Grasslikes 120–216 Letterman's needlegrass ACLE9 Achnatherum lettermanii 30–54 – western needlegrass ACOCO Achnatherum occidentale ssp. occidentale 30–54 – mountain brome BRMA4 Bromus marginatus 30–54 – Ross' sedge CARO5 Carex rossii 30–54 – 2 Secondary Perennial Grasses 12–60 big squirreltail ELMU3 Elymus multisetus 6–30 – bluegrass POA Poa 6–30 – Forb3 Perennial 48–144 mountain monardella MOOD Monardella odoratissima 30–54 – mule-ears WYAM Wyethia amplexicaulis 6–30 – buckwheat ERIOG Eriogonum 6–30 – lupine LUPIN Lupinus 6–30 – Shrub/Vine4 Primary Shrubs 90–162 mountain big sagebrush ARTRV Artemisia tridentata ssp. vaseyana 30–54 – currant RIBES Ribes 30–54 – snowberry SYMPH Symphoricarpos 30–54 – Tree5 Evergreen 27–126 California red fir ABMA Abies magnifica 6–30 – lodgepole pine PICO Pinus contorta 6–30 – western white pine PIMO3 Pinus monticola 6–30 – limber pine PIFL2 Pinus flexilis 3–6 – Interpretations
Animal community
Livestock Interpretations:
This site has limited use for livestock grazing due to low forage production under a closed canopy. When livestock use occurs, it is primarily the result of grazing animals transiting this site to access more productive communities.
Mountain big sagebrush is eaten by domestic livestock but has long been considered to be of low palatability, and a competitor to more desirable species.
Initial Stocking Rates
Stocking rates vary with such factors as kind and class of grazing animal, season of use and fluctuations in climate. Actual use records for individual sites, a determination of the degree to which the sites have been grazed and an evaluation of trend in site condition offer the most reliable basis for developing initial stocking rates.
Selection of initial stocking rates for given grazing units is a planning decision. This decision should be made only after careful consideration of the total resources available, evaluation of alternatives for use and treatment and establishment of objectives by the decision maker.
Example: Sample Calculations using Favorable Year production amounts:
500 lbs of available forage/ac x. 25 (Harvest Efficiency) = 125 lbs forage consumed
125 lbs/790 lbs = .16 AUMs/ac or 6.32 ac/AUM
NOTE: 790 lbs/month for one Animal Unit is used as the baseline for maintenance requirements. This equates to 30 lbs/day of air-dry forage (1000 lb cow at 2.6% of body weight). See NRCS National Range and Pasture Handbook.
Forage Value Rating
The forage value rating is not an ecological evaluation of the understory as is the range condition rating for rangeland. The forage value rating is a utilitarian rating of the existing understory plants for use be specific kinds of grazing animals.
Wildlife Interpretations:
This forest site provides food and shelter for squirrels, birds, deer, bear, bobcats, and mountain lions. Dead or dying trees provide nesting site for cavity-nesting birds and mammals. The fallen branches from these trees provide ground nesting birds and mammals. Blue grouse feed on Sierra lodgepole pine needles during the winter. The seeds are a food source for squirrels, chipmunks, birds, and mice.
Mountain big sagebrush is highly preferred and nutritious winter forage for mule deer.Hydrological functions
The hydrology of this site is characterized by heavy snowmelt in the spring, with very little precipitation in the summer months.
Recreational uses
This area would be available for hiking throughout, and biking and cross/country skiing on available dirt roads.
Wood products
The wood is used for fuel, coarse lumber, quality veneer, solid framing, plywood, printing paper, and high-quality wrapping paper, and is preferred for pulping (sulphite and thermomechanical).
PRODUCTIVE CAPACITY
Moderate quality site for tree production. Site index for lodgepole pine ranges from about 45 to 61. (Table 25, SCS, 190-V-NFM Amend.3; from Dahms, 1964. USDA FS PNW Res. Paper No.8).
Site index for red fir ranges from about 27 to 31. (Table 23, SCS, 190-V-NFM Amend.3; from Schumacher, 1928. Calif. Ag. Exp. Sta. Bull. No. 456).
Productivity Class (Red Fir): 7
Productivity Class (Lodgepole Pine): 3
CMAI* (Red fir): <96 to 107 cu ft/ac/yr;<6.7 to 7.5 cu m/ha/yr.
CMAI* (Lodgepole Pine): <36 to 50 cu ft/ac/yr; <2.5 to 3.5 cu m/ha/yr.
*CMAI: is the culmination of mean annual increment highest average growth rate of the stand in the units specified.
Basal Area (Lodgepole Pine): 139 sq. ft./acre with average D.B.H=16" and average age 126 years with SI=46.(AB36).
Basal Area (Red Fir): 139 sq. ft./acre with average D.B.H=25" and average age 133 years with SI=25.(AB36).
Basal Area (Red Fir): 300 sq. ft./acre with average D.B.H=16" and average age 103 years with SI=34.(AB98).
Basal Area (Red Fir): 300+sq. ft./acre with average D.B.H=18" and average age 143 years with SI=25(AB30).
Basal Area (Red Fir): 306 sq. ft./acre with average D.B.H=18.5" and average age 133 years (AB34).
Basal Area (Lodgepole Pine): 217 sq. ft./acre with average D.B.H=19" and average age 146 years (AB99).
Basal Area (Red Fir): 217 sq. ft./acre with average D.B.H=18" and average age 115 years (AB99).
Other products
California red fir are used for christmas trees. Cones can be used for decorations and art projects.
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.Table 7. Representative site productivity
Common name Symbol Site index low Site index high CMAI low CMAI high Age of CMAI Site index curve code Site index curve basis Citation California red fir ABMA 25 35 96 107 – – – Supporting information
Type locality
Location 1: Alpine County, CA Latitude 38° 39′ 11″ Longitude 119° 55′ 34″ General legal description Toiyabe National Forest. Other references
Fire Effects Information System[Online], http://www.fs.fed.us/database/feis
Plants Database [Online], http://www.plants.usda.gov
Lanner, Ronald M.. 1984. Trees of the Great Basin, A Natural History. Reno University of Nevada Press.
Dahms, W. G.. 1964. Data from Grass and Net Yield Tables for Lodgepole Pine. USDA FS PNW No. 8.
USDA-NRCS. 1980. National Forestry Manual - Part 537. Washington, D.C.
Potter, D. A. 1998. Forested Communities of the Upper Montane in the Central and Southern Sierra Nevada. USDA FA PSW GTR 169.
Schumacher, F. X. 1928. Normal Yeld Tables for Red Fir. Calif. Ag. Exp. Sta. Bull. No. 456).
Contributors
ALM/GKB
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
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Number and extent of rills:
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Presence of water flow patterns:
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Number and height of erosional pedestals or terracettes:
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Bare ground from Ecological Site Description or other studies (rock, litter, lichen, moss, plant canopy are not bare ground):
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Number of gullies and erosion associated with gullies:
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Extent of wind scoured, blowouts and/or depositional areas:
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Amount of litter movement (describe size and distance expected to travel):
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Soil surface (top few mm) resistance to erosion (stability values are averages - most sites will show a range of values):
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Soil surface structure and SOM content (include type of structure and A-horizon color and thickness):
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Effect of community phase composition (relative proportion of different functional groups) and spatial distribution on infiltration and runoff:
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Presence and thickness of compaction layer (usually none; describe soil profile features which may be mistaken for compaction on this site):
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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:
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Amount of plant mortality and decadence (include which functional groups are expected to show mortality or decadence):
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Average percent litter cover (%) and depth ( in):
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Expected annual annual-production (this is TOTAL above-ground annual-production, not just forage annual-production):
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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:
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Perennial plant reproductive capability:
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