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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) Pinus contorta
Shrub (1) Arctostaphylos patula
Herbaceous (1) Carex
(2) AchnatherumPhysiographic features
This site typically occurs on shoulder and backslope positions of mountains. Slopes range from 8 to 30 percent. Elevations range from 8000 to 9000 feet.
Table 2. Representative physiographic features
Landforms (1) Mountain slope
Elevation 8000 – 9000 ft Slope 8 – 30 % Aspect SE, SW, NW Climatic features
The climate is subhumid-continental with cold, moist winters and cool, dry summers. The mean annual precipitation is 35 to 55 inches, mean annual temperature is 35 to 40 degrees F., and the frost-free period is 30 to 60 days. Climate data used to support this section were derived from PRISM and is not specifically tied to any dominant climate station.
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 shallow, moderately well drained soils that formed in till derived from mixed rocks and colluvium derived from granitic rocks. Sand content in the control section averages 75 to 85 percent much of which is medium and coarser sand. Rock fragments average 35 to 50 percent, and are predominantly gravel. Lithology of the fragments are mainly granitic rocks such as granodiorite. The soil moisture is usually moist in the fall, winter, and spring and usually dry from July through early October. The soil is saturated within a 3 to 6 inch thick zone directly overlying bedrock for greater than 20 consecutive days during the spring or early summer. The soils have a typic xeric moisture regime and a cryic temperature regime. the soils have an ochric epipedon that occurs from the soil surface to 4 inches (A1 and A2 horizons). Soil series associated with this site include Granylith.
CA724 Eldorado National Forest Area, California, Parts of Alpine, Amador, El Dorado, and Placer Counties
240ty;Granylith-Hargran-Rock outcrop complex, 8 to 30 percent slopes;Granylith
CA729 Toiyabe National Forest Area, California
240;Granylith-Hargran-Rock outcrop complex, 8 to 30 percent slopes;Granylith
Table 4. Representative soil features
Surface texture (1) Very gravelly loamy coarse sand
Family particle size (1) Sandy
Drainage class Moderately well drained Permeability class Rapid Soil depth 10 – 20 in Surface fragment cover <=3" 20 – 25 % Surface fragment cover >3" 0 – 5 % Available water capacity
(0-40in)0.5 – 0.6 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)5.6 – 6.5 Subsurface fragment volume <=3"
(Depth not specified)37 – 40 % Subsurface fragment volume >3"
(Depth not specified)0 – 5 % Ecological dynamics
Wildfire is recognized as a natural disturbance that influenced the structure and composition of the climax vegetation of this woodland site. Sierra lodgepole pine establishes soon after disturbance and is moderately shade tolerant. It forms stable climax communities in the zone just above red fir and white fir-mountain hemlock forests.
Major Successional Stages of Forest
Development
HERBACEOUS: Vegetation is dominated by grasses and forbs under full sunlight. This stage is experienced for a short period after major disturbance such as crown fire or tree harvest. Skeleton forest (dead trees) remaining after fire or residual trees left following harvest have little or no affect on the composition and production of the herbaceous vegetation.
SHRUB-HERBACEOUS: Herbaceous vegetation and woody shrubs dominate the site. This stage is experienced within two to three years after fire or harvest. Various amounts of tree seedlings (less than 20 inches in height) may be present up to the point where they are obviously a major component of the vegetal structure.
SAPLING: In the absence of disturbance the tree seedlings develop into saplings (20 inches to 4.5 feet in height) with a range in canopy cover of about 5 to 10 percent. Vegetation consists of grasses, forbs and shrubs in association with tree saplings. Understory shrubs dominate the plant community.
IMMATURE FOREST: The visual aspect and vegetal structure are dominated by lodgepole pine greater than 4.5 feet in height. At this stage of forest development, the tree canopy has successfully broken through the suppression of early successional shrub communities. The young pines are still very susceptible to fire at this stage. The upper crown of dominant and co-dominant lodgepole pine are cone or pyramidal shaped. Seedlings and saplings of pines are common in the understory. Dominants are the tallest trees on the site; co-dominants are 65 to 85 percent of the highest of dominant trees. Understory vegetation is moderately influenced by a tree overstory canopy of about 10 to 20 percent.
MATURE FOREST: The visual aspect and vegetal structure are dominated by lodgepole pine that have reached or are near maximal heights for the site. Tree canopy cover ranges from 25 to 35 percent. This stage of community development is assumed to be representative of this forest site in the pristine environment.
OVER-MATURE FOREST: This stage is dominated by lodgepole pine that have reached maximal heights for the site. Understory vegetation is sparse due to tree competition, overstory shading, duff accumulation, etc. Tree canopy cover is commonly greater than 50 percent.
Fire Ecology:
Fire-return intervals in Sierra lodgepole pine forests vary. On the eastern slope where
drier conditions prevail, such fires may occur at intervals of less than 20 years. Sierra lodgepole pine is usually killed by fire because of its shallow root system and thin bark. Stand-replacing fires are related to insect attacks, particulary by pine mountain beetle, and declining vigor and high fuel loading in older stands. When fires occur in Sierra lodgepole stands, they are usually intense and extensive.
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 CommunityThis reference plant community is dominated by lodgepole pine. Western white pine and white fir often occur in the overstory. Greenleaf manzanita is the principal understory shrub. Letterman's needlegrass, western needlegrass, and Ross’ sedge are the most prevalent understory grasses and grass-like plants. Aster, rock cress, and pussypaws are common understory forbs.
An overstory canopy of 25 to 35 percent is assumed to be representative of tree dominance on this site in the pristine environment.
Overstory tree canopy composition is about 90 to 100 percent lodgepole pine with less than 5 percent western white pine and 5 percent white fir.
Forest overstory.MATURE FOREST: The visual aspect and vegetal structure are dominated by lodgepole pine that have reached or are near maximal heights for the site. Tree canopy cover ranges from 25 to 35 percent. This stage of community development is assumed to be representative of this forest site in the pristine environment.
Forest understory. Understory vegetative composition is about 55 percent grasses, 25 percent forbs, and 20 percent shrubs and young trees when the average overstory canopy is medium. Average understory production ranges from 150 to 450 pounds per acre. Understory production includes the total annual production of all species within 4.5 feet of the ground surface.
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 83 138 248 Forb 37 62 112 Tree 15 25 45 Shrub/Vine 15 25 45 Total 150 250 450 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 64–129 Letterman's needlegrass ACLE9 Achnatherum lettermanii 13–23 – western needlegrass ACOCO Achnatherum occidentale ssp. occidentale 13–23 – threadleaf sedge CAFI Carex filifolia 13–23 – Ross' sedge CARO5 Carex rossii 13–23 – 2 Secondary Perennnial Grasses 15–65 mountain brome BRMA4 Bromus marginatus 3–13 – squirreltail ELEL5 Elymus elymoides 3–13 – slender wheatgrass ELTRT Elymus trachycaulus ssp. trachycaulus 3–13 – bluegrass POA Poa 3–13 – spike trisetum TRSP2 Trisetum spicatum 3–13 – Forb3 Perennial Forbs 12–58 common yarrow ACMI2 Achillea millefolium 3–13 – rockcress ARABI2 Arabis 3–13 – lousewort PEDIC Pedicularis 3–13 – mule-ears WYAM Wyethia amplexicaulis 0–3 – Mt. Hood pussypaws CIUMU Cistanthe umbellata var. umbellata 0–3 – Shrub/Vine4 Primary Shrubs 6–26 greenleaf manzanita ARPA6 Arctostaphylos patula 3–13 – wax currant RICE Ribes cereum 3–13 – Tree5 Trees 9–39 lodgepole pine PICO Pinus contorta 3–13 – western white pine PIMO3 Pinus monticola 3–13 – Interpretations
Animal community
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.
Livestock Interpretations:
This site has low value for livestock grazing due low forage production. When livestock use occurs, it is primarily the result of grazing animals transiting this site to access more productive communities.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 site has potential for hiking, cross-country skiing, camping, big game hunting and nature study.
Wood products
Lodgepole pine provide many timber products. Thinning projects would increase the health of the forest, reduce extreme fire hazards, and maintain the natural dominance of lodgepole pine.
PRODUCTIVE CAPACITY
Low 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 PNW Research paper No. 8.)
Productivity Class : 5
CMAI*: <65 to 79 cu ft/ac/yr;
<4.6 to 5.5 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): 331+ sq. ft./acre with average D.B.H=18.6" and average age 112 years (AB21).
MANAGEMENT GUIDES AND INTERPRETATIONS:
1. LIMITATIONS AND CONSIDERATIONS
a. Significant restrictions or limitations for forest land use or management due to shallow rooting depths.
2. ESSENTIAL REQUIREMENTS
a. Protect soils from accelerated erosion.
b. Apply proper grazing management.
3. SILVICULTURAL PRACTICES
a. Harvest cut selectively or in small patches (size dependent upon site conditions) to enhance forage production.
1) Thinning and improvement cutting - Removal of poorly formed, diseased and low vigor trees for fuelwood.
2) Harvest cutting - Selectively harvest surplus trees to achieve desired spacing. Do not select only "high grade" trees for harvest.
3) Slash disposal - broadcasting slash improves reestablishment of native understory species and establishment of seeded grasses and forbs after tree harvest.
b. Prescription burning program to maintain desired canopy cover and manage site reproduction.
c. Mechanical tree removal on suitable sites to enhance forage production and manage site reproduction.
d. Pest control-porcupines can cause extensive damage and populations should be controlled.
e. Fire hazard - Fire usually not a problem in well-managed, mature stands.
Other information
Lodgepole pine has fascicles of two short needles. The Sierra logdgepole pine small cones are symmetrical and open at maturity and fall from the tree within a year. This characteristic differs from the Rocky Mountain lodgepole pine in that the cones are serotinous, remaining tightly closed and attached to the tree for many years. The cones remain tightly closed until released by wildfire when enormous numbers of tiny winged seeds fall into the ashes below.
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 lodgepole pine PICO 45 61 65 79 – – – Supporting information
Type locality
Location 1: Alpine County, CA Township/Range/Section T9N R19E S17 Latitude 38° 37′ 47″ Longitude 119° 54′ 28″ General legal description Alpine County, California; on the Toiyabe National Forest about 0.2 mile east of Border Ruffian Flat. USGS Carson Pass 7.5 minute topographic quadrangle. Location 2: Alpine County, CA Township/Range/Section T10N R19E S7 Latitude 38° 43′ 38″ Longitude 119° 55′ 33″ General legal description Toiyabe National Forest, Near Hope Valley campground. Other references
Dahms, W.G. 1964. Data From Grass And Net Yield Table For Lodgepole Pine. USDA PNW Res. Paper No. 8.
Fire Effects Information System[Online], http://www.fs.fed.us/database/feis
Lanner, Ronald M. 1984. Trees of the Great Basin, A Natural History. University of Nevada Press, Reno, NV.
Plants Database [Online], http://www.plants.usda.gov
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.
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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