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Draft. A draft ecological site description is either incomplete or has not undergone quality control and quality assurance review.
MLRA notes
Major Land Resource Area (MLRA): 022A–Sierra Nevada and Tehachapi Mountains
Major Land Resource Area 22A, Sierra Nevada Mountains, is located predominantly in California and a small section of western Nevada. The area lies completely within the Sierra Nevada Section of the Cascade-Sierra Mountains Province. The Sierra Nevada range is highly asymmetrical with a long, gentle western slope, and a very abrupt eastern slope. The Sierra Nevada consists of hilly to steep mountains and occasional flatter mountain valleys. Elevation ranges between 1,500 and 9,000 ft throughout most of the range, but certain peaks often exceed 12,000 ft. The highest point in the continental US occurs in this MLRA (Mount Whitney, 14,494 ft). Most of the Sierra Nevada is dominated by granitic rock of the Mesozoic age, known as the Sierra Nevada Batholith. The northern half is flanked on the west by a metamorphic belt, which consists of highly metamorphosed sedimentary and volcanic rocks of Paleozoic and Mesozoic ages. Additionally, glacial activity of the Pleistocene has played a major role in shaping Sierra Nevada features, including cirques, arêtes, and glacial deposits and moraines. Average annual precipitation ranges from 20 to 80 inches in most of the area, with increases along elevational and south-north gradients. Soil temperature regime ranges from mesic, frigid, and cryic. Due to the extreme elevational range found within this MLRA, Land Resource Units (LRUs) were designated to group the MLRA into similar land units.
LRU "A" alpine
This LRU occurs at the highest elevations of the Sierra Nevada, above treeline on upper mountain slopes, exposed ridges and mountain peaks. This LRU begins at the alpine treeline ecotone, which occurs at approximately 11,000 feet in the south and central areas and approximately 9,800 feet in the north, and extends up to 14,494 feet (Mount Whitney). Mean annual air temperature (MAAT) ranges from 29 to 35 degrees F, mean annual precipitation (MAP) ranges from 39 to 60 inches, and the frost free season is 20 to 30 days.
Classification relationships
Eleocharis quinqueflora herbaceous alliance (Sawyer et al. 2009).
Eleocharis (montevidensis, palustris, quinqueflora) Seasonally Flooded Herbaceous Alliance. Western Ecology Working Group of NatureServe. International Ecological Classification Standard: International Vegetation Classification. Terrestrial Vegetation. NatureServe, Boulder, CO.Ecological site concept
This ecological site occurs above timberline on moist, depressional benches among granitic bedrock. Soils are sandy-skeletal and are shallow to bedrock. Topographic depressions accumulate runoff, and shallow soils are inundated after spring snowmelt, creating a wetland environment that is dominated by obligate and facultative wetland species, but that also includes upland species. Fewflower spikerush (Eleocharis quinqueflora) and Sierra pussytoes (Antennaria pulchella) dominate. Diversity and variability in the plant community is high, with the length of soil inundation driving vegetation composition, and drier microsites supporting upland forbs and grasses. These areas are considered depressional seasonal meadows (Weixelman et al. 2011).
Table 1. Dominant plant species
Tree Not specified
Shrub Not specified
Herbaceous (1) Eleocharis quinqueflora
(2) Antennaria pulchellaPhysiographic features
This site occurs on moist gently sloping alpine benches among granitic outcrops. Slopes range from - to – percent. Elevations are range from - to - feet. Runoff class is - to -.
Table 2. Representative physiographic features
Landforms (1) Mountain
Climatic features
The climate of this ecological site is characterized by cool temperatures, wet winters with most precipitation falling as snow in winters, and relatively dry summers. The mean annual precipitation ranges from - to - inches. The mean annual temperature ranges from - to - degrees F. The frost-free (>32F) season is - to – days. The freeze-free (>28F) season is - to - days.
Table 3 Representative climatic features
Frost-free period (average) 0 days Freeze-free period (average) 0 days Precipitation total (average) 0 in BarLineFigure 1. Monthly precipitation range
BarLineFigure 2. Monthly average minimum and maximum temperature
Figure 3. Annual precipitation pattern
Figure 4 Annual average temperature pattern
">Influencing water features
This site is a Depressional Seasonal Meadow (Weixelman et al. 2011). Runoff, snowmelt and precipitation accumulate in topographic depressions, leading to seasonal inundation, but not perennial standing water. The dominant hydrological processes are seasonal fluctuations in water levels (Weixelman et al. 2011).
Soil features
The soils associated with this ecological site are shallow over granitic bedrock, and formed in colluvium over residuum derived from granite. They are - to - drained with - permeability. The soil moisture regime is typic xeric and the soil temperature regime is cryic. Surface rock fragments smaller than 3 inches in diameter range from - to - percent cover, and larger fragments range from - to - percent. Surface textures are very gravelly loamy sand. Subsurface textures are very and extremely gravelly loamy sand. Subsurface rock fragments smaller than 3 inches in diameter range from - to - percent by volume, and larger fragments range from - to - percent (for a depth of 0 to - inches). The soils correlated to this site include - (Sandy-skeletal, Lithic Cryorthents).
This ecological site has been correlated with the following mapunits and soil components in the Sequoia and Kings Canyon National Parks soil survey area (CA792):
Area_sym ; Musym ; MUname ; Compname ; Local_phase ; Comp_pct
Ecological dynamics
Abiotic factors
This ecological site occurs above timberline on moist, depressional benches among granitic bedrock. Soils are sandy-skeletal and are shallow to bedrock. Topographic depressions accumulate runoff, and shallow soils are inundated after spring snowmelt, creating a wetland environment that is dominated by obligate and facultative wetland species, but that also includes upland species. Fewflower spikerush and Sierra pussytoes dominate. Diversity and variability in the plant community is high, with the length of soil inundation driving vegetation composition, and drier microsites supporting upland forbs and grasses. These areas are considered depressional seasonal meadows (Weixelman et al. 2011).
Depressional meadows are “places where runoff accumulates in a topographic depression” (Weixelman et al. 2011). Seasonal depressional meadows do not have standing water, or standing water generally dries up by late summer (Weixelman et al. 2011). These meadows are characterized by a high degree of variation in the timing and duration of inundation.
Disturbance/Ecological factors
Fluctuations in soil moisture (i.e. drought and heavy snowpack) is the primary natural disturbance impacting this ecological site, and results in a dynamic vegetation community. Global climate change has the potential to impact this site, but is not included in the state-and-transition model. Sheep grazing in the late 1800’s and early 1900’s was intense and ubiquitous in the Sierra Nevada (e.g. Ratliff 1974, Vankat and Major, 1978, Benedict 1983, Ratliff 1985, Odion et al. 1988), and may have impacted this site. Impacts could include trampling and compaction of soils, trampling of sensitive vegetation, and alteration of species composition by selective grazing. Data is not available for grazing impacts on this site, and they are not included in the state-and-transition model.
Perennially moist soils are typical for this ecological site, and support a community dominated by obligate (always occur in wetlands) and facultative (usually occur in wetlands) wetland species (Lichvar and Dixon 2007). The lowest part (typically the center) of the benches remains wettest for the longest time, resulting in some stratification of the plant community, with upland species found on higher and drier locations. Drought has the potential to impact this ecological site by reducing soil moisture, creating conditions that are less suitable for wetland species, and shifting dominance to upland species. Very wet years with a late snowpack and soils that are heavily inundated for the majority of the growing season will shift dominance to primarily wetland species.
An ongoing pattern of warming and decreased snowpack is predicted under global climate change scenarios for the Sierra Nevada (e.g. Hayhoe et al. 2004, Safford et al. 2012), which may have significant impacts on this ecological site, shifting it into an altered state. Recent California based climate models predict a 9 degree F increase in temperature by 2100, and more conservative models predict a 2 to 4 degree F increase in winter and 4 to 8 degree increase in summer (Safford et al. 2012). Models are more variable for precipitation, but recent models for the Sierra Nevada, predict similar to slightly less precipitation. Most models agree that summers will become drier, since more of the precipitation is predicted to come as rain, and snow melt-off will occur earlier in spring (Hayhoe et al. 2004, Safford et al. 2012). Consistently drier conditions will shift the composition of this ecological site to greater importance of upland species (similar to Community phase 1.2), and if drying is severe enough could extirpate wetland species altogether, so that vegetation become more typical of a dry gravelly alpine bench (e.g. R022AA106CA) or dry meadow.
All tabular data listed for a specific community phase within this ecological site description represent a summary of one or more field data collection plots taken in communities within the community phase. Although such data are valuable in understanding the phase (kinds and amounts of ground and surface materials, canopy characteristics, community phase overstory and understory species, production and composition, and growth), it typically does not represent the absolute range of characteristics nor an exhaustive listing of species for all the dynamic communities within each specific community phase.State and transition model
Custom diagramStandard diagram
Figure 5. R022AA102CA
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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
ReferenceCommunity 1.1
Average precipitation
Figure 6. Community phase 1.1
Figure 7. Community phase 1.1
This community phase occurs with average precipitation, plus or minus moderate variation. At the time data was collected for this site precipitation was 65 percent of average. Extremes of drought or wet may shift the vegetation to a different community phase. The vegetation is a relatively sparse, low-growing community of grasses, grasslikes and forbs, dominated by fewflowered spikerush and Sierra pussytoes. Fewflowered spikerush is a widespread obligate wetland species, that in the Sierra Nevada occurs on seasonally to permanently flooded sites (Sawyer et al. 2009). Sierra pussytoes is an uncommon facultative wetland species that occurs in meadows, snow basins, and ridges of the high Sierra, above 2800 m (Jepson 1993). Other facultative wetland species include the forbs creeping sibbaldia (Sibbaldia procumbens), alpine gentian (Gentiana newberryi), tundra aster (Oreostemma alpigenum), and the grass Idaho bentgrass (Agrostis idahoensis). Forbs that may occur in wetland or upland habitats include beardtongue (Penstemon heterodoxus), Piersons’s aster (Oreostemma piersonii), Pacific lupine (Lupinus lepidus), Mt Hood pussypaws (Cistanthe umbellata var. umbellata), and Watson’s spikemoss (Selaginella watsonii), while grasses and grasslikes include Parry’s rush (Juncus parryi), timber oatgrass (Danthonia intermedia) and spike trisetum (Trisetum spicatum). Species that are more typical of dry sites include rosy buckwheat (Eriogonum rosense) and pioneer rockcress (Arabis platysperma), and the grasses and grasslikes Poa secunda (Sandberg bluegrass), squirreltail, (Elymus elymoides), short-hair sedge (Carex filifolia) and Ross’ sedge (Carex rossii). The upland species occur on the higher margins of the site, or among exposed rock outcrop within the site.
Figure 8. Annual production by plant type (representative values) or group (midpoint values)
Table 4. Annual production by plant type
Plant type Low
(lb/acre)Representative value
(lb/acre)High
(lb/acre)Grass/Grasslike 135 180 240 Forb 85 115 150 Total 220 295 390 Table 5. Soil surface cover
Tree basal cover 0% Shrub/vine/liana basal cover 0% Grass/grasslike basal cover 0-0% Forb basal cover 0-0% Non-vascular plants 0-10% Biological crusts 0% Litter 0-10% Surface fragments >0.25" and <=3" 60-70% Surface fragments >3" 0-10% Bedrock 0-10% Water 0% Bare ground 20-30% Table 6. Canopy structure (% cover)
Height Above Ground (ft) Tree Shrub/Vine Grass/
GrasslikeForb <0.5 – – 16-35% 10-35% >0.5 <= 1 – – 4-20% 0-4% >1 <= 2 – – 0-8% – >2 <= 4.5 – – – – >4.5 <= 13 – – – – >13 <= 40 – – – – >40 <= 80 – – – – >80 <= 120 – – – – >120 – – – – Community 1.2
Drought (Provisional)This community phase is characterized by drier soils with a reduced or absent period of inundation. These conditions cause a decline in wetland species such as fewflowered spikerush, Sierra pussytoes, creeping sibbaldia, alpine gentian and Idaho bentgrass. Species that occur in both wetland and upland habitats, or that are more typical of upland habitats increase. Parry’s rush and short-hair sedge, which are common in dry gravelly soils of the high Sierra (Ratliff 1974, Weixelman et al. 2011), are likely to become dominant. Upland forbs increase in abundance and diversity. Sierra beardtongue, which is a common member of alpine fellfields (e.g. Jackson and Bliss 1984, Rundel et al. 2005) is likely to increase, as well as Pierson’s aster, Pacific lupine, pioneer rockcress, Mt Hood pussypaws, rosy buckwheat, Watson’s spikemoss, Ross’ sedge, squirreltail, and Sandberg bluegrass. Other upland species are likely to colonize this phase as well.
Community 1.3
Wet (Provisional)This community phase is characterized by a long period of inundation with an increase in soil moisture. These conditions cause an increase in wetland species dominance, while upland species decline in importance, and are restricted to fringes of the site. Fewflowered spikerush is strongly dominant.
Pathway 1.1a
Community 1.1 to 1.2Occurs with ongoing severe drought that reduces soil moisture.
Pathway 1.1b
Community 1.1 to 1.3Occurs with recurrent very wet years that increase soil inundation length and amount.
Pathway 1.2a
Community 1.2 to 1.1This pathway occurs with a return to average precipitation conditions.
Pathway 1.2b
Community 1.2 to 1.3Occurs with recurrent very wet years that increase soil inundation length and amount.
Pathway 1.3a
Community 1.3 to 1.1This pathway occurs with a return to average precipitation conditions.
Pathway 1.3b
Community 1.3 to 1.2Occurs with ongoing severe drought that reduces soil moisture.
Additional community tables
Table 7. Community 1.1 plant community composition
Group Common name Symbol Scientific name Annual production () Foliar cover (%) Grass/Grasslike1 Grasses/Grasslikes 135–240 fewflower spikerush ELQU2 Eleocharis quinqueflora 70–116 15–25 Parry's rush JUPA Juncus parryi 30–50 6–10 Ross' sedge CARO5 Carex rossii 0–10 0–6 Sandberg bluegrass POSE Poa secunda 0–10 0–4 Idaho bentgrass AGID Agrostis idahoensis 5–8 1–4 timber oatgrass DAIN Danthonia intermedia 0–5 0–2 squirreltail ELEL5 Elymus elymoides 0–5 0–2 spike trisetum TRSP2 Trisetum spicatum 0–5 0–2 woodrush LUZUL Luzula 0–3 0–1 Forb2 Forbs 85–150 Sierra pussytoes ANPU8 Antennaria pulchella 35–58 10–17 Sierra beardtongue PEHE2 Penstemon heterodoxus 0–25 0–5 alpine gentian GENE Gentiana newberryi 0–5 0–5 mousetail IVESI Ivesia 0–5 0–5 pale yellow lupine LULU2 Lupinus luteolus 0–5 0–5 tundra aster ORALA2 Oreostemma alpigenum var. alpigenum 0–5 0–5 creeping sibbaldia SIPR Sibbaldia procumbens 0–5 0–5 Watson's spikemoss SEWA2 Selaginella watsonii 0–5 0–2 rosy buckwheat ERRO Eriogonum rosense 0–3 0–1 Peirson's aster ORPE4 Oreostemma peirsonii 0–1 0–1 alpine sheep sorrel RUPA6 Rumex paucifolius 0–1 0–1 pioneer rockcress ARPL Arabis platysperma 0–1 0–1 Mt. Hood pussypaws CIUMU Cistanthe umbellata var. umbellata 0–1 0–1 Table 8. Community 1.2 plant community composition
Group Common name Symbol Scientific name Annual production () Foliar cover (%) Table 9. Community 1.3 plant community composition
Group Common name Symbol Scientific name Annual production () Foliar cover (%) Interpretations
Animal community
Yellow bellied marmot (Marmota flaviventris), American pika (Ochotona princeps), and Sierra bighorn sheep (Ovis canadensis sierrae) may use this ecological site.
Hydrological functions
Community Phase 1.1
Soils are inundated after spring snowmelt, and soil is moist for most of the year.
Community Phase 1.2
Soils are briefly inundated, or inundation is absent.
Community Phase 1.3
Soils are inundated for a longer period and with a greater amount due to heavy snowpack, and remain moist for the year.
Recreational uses
This is a scenic alpine area with backcountry camping and hiking use.
Supporting information
Inventory data references
High intensity sampling (Caudle et al. 2013) was used to describe this ecological site. Site characteristics such as aspect, slope, elevation and UTMS were recorded for each plot, along with complete species inventory by ocular percent cover. The line-point intercept method was used to measure foliar cover, groundcover, and vegetation structure. At 100 points along a 400-foot step transect, ground cover and intercepted plant species were recorded by height. The first hit method (Herrick et al. 2009) was used to generate the foliar cover values entered in the community phase composition tables. Annual production was estimated using the double-weight sampling method outlined in the National Range and Pasture Handbook and in Sampling Vegetation Attributes (NRCS 2003 and Interagency Technical Reference 1999 pgs. 102 - 115). For herbaceous vegetation, ten 9.6 square foot circular sub-plots were evenly distributed along a 200 foot transect. For woody and larger herbaceous species production was estimated in four 21’X21’ square plots along the same transect. Weight units were collected for each species encountered in the production plots. The number of weight units for each species is then estimated for all plots. The following plot was used to describe this ecological site: 2013CA7927038 (Type location)
Type locality
Location 1: Fresno County, CA UTM zone N UTM northing 4088202 UTM easting 374426 General legal description The type locality is approximately half a mile southeast of Pinchot Pass in Kings Canyon National Park. Other references
Caudle, D., H. Sanchez, J. DiBenedetto, C. Talbot, and M. Karl. 2013. Interagency ecological site handbook for rangelands. USDA-NRCS, USDA-FS, DOI-BLM.
Benedict, N. B. 1983. Plant associations of subalpine meadows, Sequoia National Park, California. Arctic and Alpine Research 15:383-396.
Hayhoe, K., D. Cayan, C. B. Field, P. C. Frumhoff, E. P. Mauren, N. L. Miller, S. C. Moser, S. H. Schneider, K. N. Cahill, E. E. Cleland, L. Dale, R. Drapek, R. M. Hanemann, L. S. Kalkstein, J. Lenihan, C. K. Lunch, R. P. Neilson, S. C. Sheridan, and J. H. Verville. 2004. Emissions pathways, climate change, and impacts on California. Proceedings of the National Academy of Sciences 101.
Jackson, L. E. and L. C. Bliss. 1984. Phenology and water relations of three plant life forms in a dry tree-line meadow. Ecology 65:1302-1314.
Jepson, W. L. 1993. The Jepson manual: higher plants of California. University of California Press, Berkeley, CA.
Lichvar, R. and L. Dixon. 2007. Wetland plants of specialized habitats in the Arid West. Engineering Research and Development Center, Cold Regions Research and Engineering Lab, Hanover, N.H.
Odion, D. C., T. L. Dudley, and C. M. D'Antonio. 1988. Cattle grazing in southeastern Sierran meadows: ecosystem chane and prospects for recovery. Pages 277-292 Plant biology of eastern California. White Mountain Research Station, University of California, Los Angeles.
Ratliff, R. D. 1974. Short-hair sedge--its condition in the high Sierra Nevada of California. Forest Service, US Dept. of Agriculture, Pacific Southwest Forest and Range Experiment Station.
Rundel, P. W., A. C. Gibson, and M. R. Sharifi. 2005. Plant functional groups in alpine fellfield habitats of the White Mountains, California. Arctic, Antarctic, and Alpine Research 37:358-365.
Safford, H. D., M. North, and M. D. Meyer. 2012. Climate change and the relevance of historical forest conditions. Pages 23-45 in M. North, editor. Managing Sierra Forests. U.S. Department of Agriculture, Forest Service, Pacific Southwest Research Station, Albany, CA.
Sawyer, J. O., T. Keeler-Woolf, and J. M. Evans. 2009. A manual of California vegetation. 2nd edition. California Native Plant Society, Sacramento, California.
Vankat, J. L. and J. Major. 1978. Vegetation changes in Sequoia National Park, California. Journal of Biogeography 5:377-402.
Weixelman, D. A., B. Hill, D. J. Cooper, E. L. Berlow, J. H. Viers, S. E. Purdy, A. G. Merrill, and S. E. Gross. 2011. A field key to meadow hydrogeomorphic types for the Sierra Nevada and Southern Cascades, CA. U.S. Department of Agriculture, Forest Service, Pacific Southwest Research Station, Vallejo, CA.
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:
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