Natural Resources
Conservation Service
Ecological site F021XE232CA
Pinus contorta var. murrayana/Arctostaphylos nevadensis/Carex rossii
Accessed: 07/01/2026
-
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
Fire Effects Information System (Online; http://www.fs.fed.us/database/feis/plants/).
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 Unpublished report.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. Element Code: 86100 - Lodgepole Pine Forest.
Sawyer, J.O. and T. Keeler-Wolf 1995. A manual of California vegetation. Lodgepole Pine Series.
Smith, S. and B. Davidson. 2003. User's Manual Terrestrial Ecological Unit Inventory (TEUI) Land Type Associations, Modoc National Forest. Lodgepole Pine Series.
USDA-NRCS. 2000 National Forestry Manual - Part 537. Washington, D.C.
USDA-NRCS. 2004 National Forestry Handbook, Title 190. Washington, D. C.
USDA-NRCS Plants Database (Online; http://www.plants.usda.gov).
Table 1. Dominant plant species
Tree (1) Pinus contorta var. murrayana
Shrub (1) Arctostaphylos nevadensis
Herbaceous (1) Carex rossii
Physiographic features
This site occurs on mountain sideslopes. Slopes range from 4 to 50 percent. Elevations range from 7400 to 8400 feet.
Table 2. Representative physiographic features
Landforms (1) Mountain slope
Elevation 7400 – 8400 ft Slope 4 – 50 % Aspect Aspect is not a significant factor Climatic features
The climate of this site is subhumid, characterized by cool, 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 30 to 50 inches with most occurring during the winter months. Approximately half the precipitation falls as snow; half as rain.
Table 3 Representative climatic features
Frost-free period (average) 60 days Freeze-free period (average) 0 days Precipitation total (average) 50 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, well drained soils that formed in volanic ash and colluvium over residuum derived from glassy tuff. The soils have high amounts of vitric volanic ash and glass throughout the profile which enhances the waterholding capacity. Soil profiles are modified with 60 to 80 percent rock fragments, mainly gravels. Soil series associated with this site include Gurlidawg.
Table 4. Representative soil features
Parent material (1) Colluvium – tuff
Surface texture (1) Ashy loam
Family particle size (1) Loamy
Drainage class Well drained Permeability class Moderate Soil depth 20 – 40 in Surface fragment cover <=3" 35 – 45 % Surface fragment cover >3" Not specified Available water capacity
(0-40in)4 – 6 in Soil reaction (1:1 water)
(0-40in)5.2 – 6.2 Subsurface fragment volume <=3"
(Depth not specified)35 – 80 % Subsurface fragment volume >3"
(Depth not specified)Not specified Ecological dynamics
Major Successional Stages of Forestland 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 a 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, such as pinemat manzanita and yellow rabbitbrush, 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 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 Forestland: 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 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. Understory vegetation is moderately influenced by a tree overstory canopy of about 10 to 20 percent.
Mature Forestland: 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 30 to 50 percent. This stage of community development is assumed to be representative of this site in the pristine environment.
Over-Mature Forestland: 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, and duff accumulation. Tree canopy cover is commonly greater than 50 percent.
Fire return intervals for Sierra lodgepole pine forests range from 35 to 200 years. Stand-replacing fires would occur on this site due to the density of trees.
Small or moderate-intensity fires are thought to favor perpetuation of the lodgepole habitat. The mature lodgepole trees have very thin bark, deep roots, and medium to low foliage flammability and are considered intermediate in fire tolerance. Mature lodgepole trees are most commonly killed by scorching cambium or crowning. Lodgepole seedlings are shade tolerant and but require openings for growth. The seeds germinate best in openings and sterilized mineral seedbeds produced by high-intensity fire. After a stand-replacing fire, it typically establishes from wind-dispersed seed and developments into even-aged stands. Smaller-scale disturbances such as windfall and avalanches are thought to convert Sierra lodgepole pine forests to the uneven-aged structure typical of this variety. The exclusion of fire may allow for the encroachment of white fir.
Pinemat manzanita prefers well drained, acidic soils in open sunny sites. It has a high tolerance for cold, below-freezing winters, and depends on snow cover to protect dormant buds. Occasional fires may be important to successful seed germination and establishment.
Fire Ecology:
Pinemat manzanita establishes from seed during the first postfire growing season. It may be an obligate seeder, requiring fire and/or charred wood lechate to break seed dormancy. The seed, however, has not been tested under laboratory or other conditions for such
fire-stimulated germination responses. Wax currant regeneration is favored by short-duration, low-severity fire because soil-stored seed requires scarification to germinate. Most wax currant plants are severely damaged or killed by fire. The ability of wax currant to sprout after fire is described in the literature as weak. Sedge is top-killed by fire, with rhizomes protected by insulating soil. The rhizomes of sedge species may be killed by high-severity fires that remove most of the soil organic layer. Reestablishment after fire occurs by seed establishment and/or rhizomatous spread. Western needlegrass is moderately damaged by fire. The recovery time is between 3 and 5 years.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
The reference plant community is dominated by a dense forest of slender trees up to 75 feet tall, often in nearly pure stands of lodgepole pine. The trees in the dense stands are relatively short-lived, and if the stand has not burned for a long time, fallen trees, branches and needles cover the ground. The understory is normally sparse in these dense stands, but low shrubs and perennial forbs and grasses occur abundantly in the forest openings. Pinemat manzanita, currant and snowberry are common shrubs. The dominant understory grasses and grasslike plants include Ross' sedge, Wheeler's bluegrass and western needlegrass. Sandworts, lupine, and spreading phlox are common perennial forbs. Approximate understory cover (basal and canopy) ranges from 20 to 30 percent. Overstory canopy cover is typically 30 to 40 percent.
Forest overstory.Mature Forestland: 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 30 to 40 percent. This stage of community development is assumed to be representative of this site in the pristine environment.
Forest understory. Understory vegetation is approximately 50 percent grasses and grasslike plants, 15 percent forbs and 35 percent shrubs and young trees when the average overstory canopy is medium (30 to 40 percent). 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 75 150 225 Shrub/Vine 45 90 135 Forb 23 45 68 Tree 7 15 22 Total 150 300 450 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 60–128 western needlegrass ACOCO Achnatherum occidentale ssp. occidentale 30–72 – Ross' sedge CARO5 Carex rossii 15–27 – Wheeler's bluegrass POWH2 Poa wheeleri 15–27 – 2 Secondary Perennial Grasses/Grasslikes 12–60 mountain brome BRMA4 Bromus marginatus 3–15 – squirreltail ELEL5 Elymus elymoides 3–15 – Parry's rush JUPA Juncus parryi 3–15 – Bolander's bluegrass POBO Poa bolanderi 3–15 – Forb3 Perennial 14–42 tailcup lupine LUCAC3 Lupinus caudatus ssp. caudatus 3–15 – woolly mule-ears WYMO Wyethia mollis 3–15 – spreading phlox PHDI3 Phlox diffusa 2–3 – prickly sandwort ARAC2 Arenaria aculeata 2–3 – King's sandwort ARKI Arenaria kingii 2–3 – buckwheat ERIOG Eriogonum 2–3 – Shrub/Vine4 Primary Shrubs 60–108 pinemat manzanita ARNE Arctostaphylos nevadensis 15–27 – wax currant RICE Ribes cereum 15–27 – sticky currant RIVI3 Ribes viscosissimum 15–27 – roundleaf snowberry SYRO Symphoricarpos rotundifolius 15–27 – Tree5 Evergreen 7–21 Sierra lodgepole pine PICOM Pinus contorta var. murrayana 3–15 – western white pine PIMO3 Pinus monticola 2–3 – Table 7. Community 1.1 forest overstory composition
Common name Symbol Scientific name Nativity Height ft Canopy cover (%) Diameter in Basal area (square ft/acre) TreeSierra lodgepole pine PICOM Pinus contorta var. murrayana Native – 95-100 – 0 western white pine PIMO3 Pinus monticola Native – 0-4 – 0 Interpretations
Animal community
Livestock Interpretations:
This site is suited to cattle and sheep grazing during the summer and fall. Grazing management should be keyed to perennial grass production. New plants of these grasses are established entirely from seed and grazing practices should allow for ample seed production and seedling establishment periodically. Prescribed grazing can also be used to promote estalishment and growth of conifer seedlings when numbers, distribution and timing are controlled. Sedge provides good to fair forage for domestic grazing. Western needlegrass has a spreading and deeply penetrating root system, which makes it resistant to trampling. Wax current is fair to poor browse for livestock. Mature pinemat manzanita browse is unpalatable to all classes of livestock. Foliage of older plants is rarely consumed by livestock. Snowberry is readily eaten by all classes of livestock, particularly domestic sheep.
Livestock will often concentrate on this site taking advantage of the shade and shelter offered by the tree overstory. Many areas are not used because of steep slopes or lack of adequate water. Attentive grazing management is required due to steep slopes and erosion hazards.
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:
Black bear, black-tailed deer, coyote, and various birds and rodents eat pinemat manzanita fruits. Black-tailed deer browse seedlings for the first 3 years following fire. Foliage of older plants is rarely consumed by wildlife. Mature pinemat manzanita browse is unpalatable to all classes of wildlife. Snowberry is an important forage species for deer and elk on high elevation summer ranges. Snowberry is frequently one of the first species to leaf out, making it a highly sought after food in the early spring. Sedges have a high to moderate resource value for elk and a medium value for mule deer. Elk consume beaked sedge later in the growing season. Western needlegrass provides valuable forage for many species of wildlife. Wax currant provides food and cover for wildlife. It is only fair to poor browse for deer, but it is important on ranges where little else is available. Lodgepole pine forests provide food, cover and habitat for several species of mammals and birds. Dead or dying trees provide nesting sites for cavity-nesting birds. The fallen branches from these trees provide sites for ground-nesting birds and small mammals. Dense stands of lodgepole pine provide excellent escape and resting cover for deer and elk. The seeds are a valuable food source for squirrels, chipmunks, birds, and mice.Hydrological functions
Runoff ranges from medium to high depending on slope.
Wood products
The wood of lodgepole pine is suited for common lumber grades, and used for light framing materials, interior paneling, exterior trim, posts, railroad ties, pulp and paper, and has potential for structural particle board.
Other products
The fruit of wax currant is used for making jam, jelly, or pie. Some western Indian tribes used currants for making pemmican. Wax currant is cultivated as an ornamental.
Table 8. 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 Sierra lodgepole pine PICOM 40 61 31 50 – – – Supporting information
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
