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Conservation Service
Ecological site R241XY111AK
Alpine Sedge-Scrub Frozen Loamy Slopes
Last updated: 5/29/2025
Accessed: 10/07/2026
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Provisional. A provisional ecological site description has undergone quality control and quality assurance review. It contains a working state and transition model and enough information to identify the ecological site.
MLRA notes
Major Land Resource Area (MLRA): 241X–Seward Peninsula Highlands
The Seward Peninsula Highlands (MLRA 241X) occurs in Western Alaska, along the southernmost reaches of Land Resource Region Y, which has an arctic climate and occurs in the zone of continuous permafrost. This MLRA is approximately 13,700 square miles across the central Seward Peninsula. The terrain is defined by broad and extensive rolling hills and plains and solitary groups of rugged mountains expanding from sea level to a high point of 4,714 feet on Mount Osborn. Flood plains systems are common but generally narrow. The MLRA 241X watershed drains into Kotzebue Sound and the Chukchi Sea to the north and the Bering Sea to the West. Major rivers include the Buckland, Kiwalik, Serpentine, Agiapuk-American, Kougarok, and Kuzitrin Rivers. The area is mostly undeveloped wild land that is sparsely populated. Residents use this remote area primarily for subsistence hunting, fishing, and gathering. The largest communities in this predominantly inland MLRA are along the coast and include Teller and Brevig Mission. Reindeer herding is a profitable enterprise and many areas of this MRLA are used for reindeer graze and subsistence activities. Parts of this MLRA were mined for gold during the Nome gold rush. Several mines still operate within this boundary (USDA, 2022). Federally managed lands in this MLRA include parts of the Selawik National Wildlife Refuge and parts of Bering Land Bridge National Preserve.
Geology and Soils
MLRA 241X was mostly unglaciated during the late Pleistocene. Glaciers were present during the middle and early Pleistocene in scattered areas such as the York Mountains in the west, the Kiglauik Mountains to the south, and the Upper Kiwalik River drainage. The present-day landscape is mantled with loess, colluvium, and slope alluvium (USDA, 2022). Modified glacial moraines are evident in areas of past glacial activity. Bedrock material is a mix of rock types, with areas of sedimentary, volcanic and igneous throughout the MLRA. Bedrock is at or near the surface in most upland areas of this MLRA, which is reflected in soil development and vegetative patterns.
This MLRA is in the zone of continuous permafrost. Frozen soils are common across the landscape, though may be absent from high energy systems on floodplains, around lakes and on gravelly, well drained soils. Permafrost is generally shallow to moderately deep (10 to 40 inches) that results in a restrictive layer that perches water and creates poorly to very poorly drained soils. Alongside these permafrost soils (Gelisols), other common soil orders include soils with little to no development in the Entisol and Inceptisol orders. Periglacial features are common and include solifluction lobes, polygonal ground, and thermokarst pits (USDA, 2022). Non-soil areas (rock outcrop, riverwash, and surface water) make up approximated five percent of the MLRA surface.
Climate
Climate is predominantly continental arctic, with brief, cool summers and long, cold winters. Maritime conditions, where summer temperatures are moderated by the proximity to open water, persist through the summer along the Bering Sea coast. Mean annual precipitation is 10 to 15 inches in the north and west, increasing to 20 to 40 inches in the mountainous areas in the south and east (USDA, 2022). Mean annual temperatures ranges from 20 to 26 degrees Fahrenheit (PRISM, 2018; SNAP, 2014).
Vegetation
Vegetation is mainly influenced by climate, site, and soil characteristics such as temperature-degree days, elevation, exposure to wind, soil depth, and soil hydrology. Dwarf scrublands are present across most of the upland, with vegetation further restricted on shallow soils. Lower elevations generally support more developed soils, and host willow-sedge scrublands, mixed ericaceous shrub scrublands, and herbaceous graminoid meadows. Tussock tundra is ubiquitous across much of the poorly drained, low-sloped landforms across the MRLA. Wetland communities dominate in closed depressions and drainages (USDA, 2022).LRU notes
There are currently no Land Resource Areas (LRUs) delineated or described in MLRA 241X. There is potential for two or more LRUs along a climatic break between the lowlands and low-elevation hills of the north and west, and the higher, mountainous regions more prevalent in the south and east. However, vegetation and land management may not differ between these areas, as soils and vegetation are already restricted by cold annual temperatures even at low elevations.
Classification relationships
Alaska Vegetation Classification:
Open low scrub (II.C.2 - level III) / Mesic shrub birch – ericaceous shrub (II.C.2.c – level IV)
(Viereck et al., 1992)
BioPhysical Settings: 6816821 – Alaska Arctic Scrub Birch – Ericaceous Shrubland
(LANDFIRE, 2009)
Seward Rangesites
32 – Mixed shrub
(SCS, 1984; Swanson et al., 1985)Ecological site concept
Ecological Site characteristics:
• Associated with alpine mountain footslopes and toeslopes
• Soils are wet and support permafrost and are considered very poorly drained
• The reference plant community is an open scrubland of ericaceous shrubs and birch
• There is no major disturbance affecting vegetation recorded for this ecological site
• Non-sorted circles are common periglacial features on the described landform. These are represented by an alternate state.Associated sites
R241XY134AK Arctic Scrub Loamy Hillslopes
R241XY134AK describes a low scrubland with tussocks on permafrost soil. It is susceptible to fire.
R241XY117AK Alpine Dwarf Scrub Gravelly Summits
This alpine ecological site is on upper mountain, steep slopes. Soils are dry and gravelly and support a Dryas shrubland.
Similar sites
R241XY134AK Arctic Scrub Loamy Hillslopes
Both are associated with cold, wet permafrost soils. R241XY111AK is an alpine site, with a shorter growing season that supports a unique vegetative community.
Table 1. Dominant plant species
Tree Not specified
Shrub (1) Ledum palustre ssp. decumbens
(2) Betula nanaHerbaceous (1) Carex bigelowii
(2) Rubus chamaemorusPhysiographic features
This ecological site occurs on mountain alpine footslopes. Elevation ranges from 1,000 to 3,000 feet above sea level. Slope gradients are nearly level to strongly sloped (0 to 16 percent). This ecological site occurs on all aspects. Ponding is long and frequent. A shallow to moderately deep water table is present during the growing season.
Non-sorted circles are common periglacial microfeatures. They can be mounded well above the surrounding vegetation. Non-sorted circles have unique site and soil properties that result in a mosaic of vegetation and generally have drier soils compared to the reference state.Table 2. Representative physiographic features
Slope shape across (1) Linear
Slope shape up-down (1) Linear
Hillslope profile (1) Footslope
(2) Toeslope
Landforms (1) Mountains > Mountain
(2) Mountains > Mountain
(3) Mountains > Mountain > Nonsorted circle
Runoff class Negligible to medium Flooding frequency None Ponding duration Long (7 to 30 days) Ponding frequency Frequent Elevation 1000 – 3000 ft Slope 0 – 16 % Ponding depth 0 – 24 in Water table depth 0 – 39 in Aspect W, NW, N, NE, E, SE, S, SW Table 3. Representative physiographic features (actual ranges)
Runoff class Not specified Flooding frequency Not specified Ponding duration Long (7 to 30 days) Ponding frequency None to frequent Elevation 0 ft Slope 0 % Ponding depth 0 in Water table depth 0 in Climatic features
The alpine climate of this ecological site includes short, cool growing seasons and long, cold winters. Mean annual temperature ranges from 17 to 29 degrees Fahrenheit, with temperatures typically below freezing from October through April. Approximately 35 percent of total precipitation occurs during the growing season months of June through August. Across the MLRA, snowfall ranges from 40 to 100 inches (USDA-NRCS, 2022).
Table 4 Representative climatic features
Frost-free period (characteristic range) 50-80 days Freeze-free period (characteristic range) 40-70 days Precipitation total (characteristic range) 10-20 in Frost-free period (actual range) 40-80 days Freeze-free period (actual range) 30-70 days Precipitation total (actual range) 10-30 in Frost-free period (average) 60 days Freeze-free period (average) 50 days Precipitation total (average) 20 in Characteristic rangeActual rangeBarLineFigure 1. Monthly precipitation range
Characteristic rangeActual rangeBarLineFigure 2. Monthly minimum temperature range
Characteristic rangeActual rangeBarLineFigure 3. Monthly maximum temperature range
BarLineFigure 4. Monthly average minimum and maximum temperature
Figure 5. Annual precipitation pattern
Figure 6 Annual average temperature pattern
">Influencing water features
This site is not associated with or influenced by streams or wetlands. Precipitation and throughflow are the main source of water for this ecological site. Surface runoff and throughflow contribute water to downslope ecological sites.
Wetland description
This ecological site may be classified as a slope wetland under the Hydrogeomorphic (HGM) classification system (Smith et al. 1995; USDA-NRCS 2008). A shallow water table is present in the reference state throughout the year
Soil features
Soils in the reference state are frozen, highly organic Historthels (Soil Survey Staff, 2013). Soils developed in loamy or gravelly till. Surface rock fragments are mostly absent... Soils in the reference state support a thick organic mat (8 to 15 inches) that insulates the soil and supports permafrost. Soils are very deep, though permafrost is a root-limiting layer. Subsurface rock fragment volume is moderate at around 20 percent. Soil pH is extremely to slightly acidic. Soils in the reference state are very poorly drained.
Soils in the alternate state are frozen, wet Aquiturbels. Non-sorted circles have unique soil properties distinct from the reference state. Soils are drier and cryoturbated with surface rock fragments present, and a greater volume of subsurface rock fragments.Table 5. Representative soil features
Parent material (1) Colluvium
(2) Cryoturbate
(3) Eolian deposits
Surface texture (1) Silt loam
(2) Peat
Drainage class Very poorly drained Permeability class Moderate Depth to restrictive layer 11 – 15 in Soil depth 60 – 0 in Surface fragment cover <=3" Not specified Surface fragment cover >3" 0 – 1 % Available water capacity
(0-40in)3.2 – 4.2 in Soil reaction (1:1 water)
(0-10in)4.2 – 6.5 Subsurface fragment volume <=3"
(0-30in)19 – 20 % Subsurface fragment volume >3"
(0-60in)0 – 2 % Table 6. Representative soil features (actual values)
Drainage class Very poorly drained to moderately well drained Permeability class Not specified Depth to restrictive layer 0 in Soil depth 0 in Surface fragment cover <=3" 0 % Surface fragment cover >3" 0 % Available water capacity
(0-40in)0 in Soil reaction (1:1 water)
(0-10in)0 Subsurface fragment volume <=3"
(0-30in)0 % Subsurface fragment volume >3"
(0-60in)0 % Ecological dynamics
The low scrub reference plant community is shaped by factors including cold annual air temperatures and soil wetness caused by permafrost and seasonal melt. Snow pack may further shorten an already short growing season in some concave footslope positions.
Site and soil conditions result in one community that changes little over time (Viereck et al., 1992). Cool temperatures and a shortened growing season support slow growing, often evergreen shrubs. Average shrub height is taller here than in more exposed, convex slopes. Soils are cold and wet and support permafrost. Cryoturbation is generally absent from the reference state, but is present in the alternate state, which limits plant rooting.
One alternate state is recognized in this ecological site. Non-sorted circles are a type of patterned ground that is not managed for. On gentle slopes, these patterned features are roughly circular and become elongated as steepness increases. These circles are considered non-sorted due to an absence of coarse rock fragments on their borders (Schoeneberger and Wysocki 2017). The formation of these non-sorted circles leads to a distinct mosaic of vegetation.
Non-sorted circles have distinct plant communities that are associated with different positions on the non-sorted circle. The first plant community (2.2) occurs between non-sorted circles and generally resembles the reference plant community. Plant community 2.2 is classified as open low scrub (Viereck et al. 1992). The second community is in the circle center and is mostly unvegetated area with high surface rock fragments (community 2.1).
The information in this Ecological Dynamics section, including the state-and-transition model (STM), was developed based on current field data, professional experience, and a review of the scientific literature. As a result, all possible scenarios or plant species may not be included. Key indicator plant species, disturbances, and ecological processes are described to inform land management decisions.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
T1A - Nonsorted circle creation R2A - Cessation of microfeature freezing processes State 1 submodel, plant communities
State 2 submodel, plant communities
2.1A - Frost heave sorting 2.2A - Frost heave sorting State 1
Reference StateThis reference state is developed and characterized using available vegetation models, most notably United States Department of Agriculture - Soil Conservation Service range surveys (SCS, 1984; Swanson et al., 1985).
The reference state describes one distinct vegetative community on frozen slopes. Exposure to wind and low annual temperatures restrict vegetation height. The reference state appears to be stable (Viereck et al., 1992) and does not appear to be susceptible to fire.
There is no indication of an alternate grazing state on this site. Targeted data collection may be able to address whether grazing or browsing in the reference state result in an alternate state.Dominant plant species
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marsh Labrador tea (Ledum palustre ssp. decumbens), shrub
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dwarf birch (Betula nana), shrub
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black crowberry (Empetrum nigrum), shrub
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netleaf willow (Salix reticulata), shrub
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eightpetal mountain-avens (Dryas octopetala), shrub
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sedge (Carex), grass
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cottongrass (Eriophorum), grass
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Altai fescue (Festuca altaica), grass
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cloudberry (Rubus chamaemorus), other herbaceous
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field horsetail (Equisetum arvense), other herbaceous
Community 1.1
Ledum palustre ssp decumbens - Betula nana / Carex bigelowii - Rubus chamaemorusThis community is an open low scrubland (Viereck et al., 1992). The major plant groups are low shrubs, dwarf shrubs, medium graminoids, and medium forbs (Swanson et al., 1985). Plant height is restricted by wind exposure. Community structure including plant height and composition are restricted by permafrost, which creates a root-restrictive layer and supports wet soils. Ground cover is a mix of mosses, lichen, and herbaceous litter.
Tabular data for this community is from the 1984 Seward range site publication (SCS, 1984), with supplemental information from Swanson et al. (1985).
Forest understory. Live lichen and moss annual production cannot be measured accurately due to a lack of information on growth rates and/or slow annual growth rates. Lichen and moss biomass data below refers to total biomass, while vascular plants biomass refers to annual production.
Dominant plant species
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marsh Labrador tea (Ledum palustre ssp. decumbens), shrub
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dwarf birch (Betula nana), shrub
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bog blueberry (Vaccinium uliginosum), shrub
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black crowberry (Empetrum nigrum), shrub
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netleaf willow (Salix reticulata), shrub
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eightpetal mountain-avens (Dryas octopetala), shrub
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sedge (Carex), grass
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cottongrass (Eriophorum), grass
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Altai fescue (Festuca altaica), grass
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cloudberry (Rubus chamaemorus), other herbaceous
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field horsetail (Equisetum arvense), other herbaceous
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arctic sweet coltsfoot (Petasites frigidus), other herbaceous
Figure 7. Annual production by plant type (representative values) or group (midpoint values)
Table 7. Annual production by plant type
Plant type Low
(lb/acre)Representative value
(lb/acre)High
(lb/acre)Moss 940 2030 3020 Lichen 65 340 610 Shrub/Vine 395 455 500 Grass/Grasslike 180 210 230 Forb 145 165 180 Total 1725 3200 4540 Table 8. Ground cover
Tree foliar cover 0% Shrub/vine/liana foliar cover 30-50% Grass/grasslike foliar cover 10-30% Forb foliar cover 30-50% Non-vascular plants 30-60% Biological crusts 0% Litter 10-30% Surface fragments >0.25" and <=3" 0% Surface fragments >3" 0-10% Bedrock 0% Water 0-10% Bare ground 0-10% State 2
Nonsorted Circle StateThis state is developed and characterized using available vegetation models and published literature and is supplemented with field experience.
This state describes two communities that make up nonsorted circles. The inner part of the circle is often unvegetated and is dominated by surface rock fragments and bare soil. The circle ring is comprised of similar vegetation to that of the reference state. This community does not appear to be susceptible to fire. Exposure to wind and low annual temperatures restrict vegetation height.
The historic and current use of introduced ungulates in MLRA 241X may have altered the potential natural vegetation on this ecological site. No data indicates an alternate grazing state on this site. Targeted data collection may be able to address whether grazing or browsing in the reference state result in an alternate state.Dominant plant species
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eightpetal mountain-avens (Dryas octopetala), shrub
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black crowberry (Empetrum nigrum), shrub
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sedge (Carex), grass
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Altai fescue (Festuca altaica), grass
Community 2.1
Nonsorted Circle CenterVegetation in this community is sparse or absent. Surface rock fragments and bare soil make up the majority of ground cover.
Table 9. Ground cover
Tree foliar cover 0% Shrub/vine/liana foliar cover 0-0% Grass/grasslike foliar cover 0-0% Forb foliar cover 0-0% Non-vascular plants 0-10% Biological crusts 0% Litter 0% Surface fragments >0.25" and <=3" 20-50% Surface fragments >3" 10-20% Bedrock 0% Water 0% Bare ground 50-80% Community 2.2
Nonsorted Circle EdgeThis community is a dwarf scrubland (Viereck et al., 1992). It is typically made up of species present in the reference state. Community composition of nonsorted circle ring vegetation varies between and within areas. Plant height is restricted by wind exposure. This community supports a mix of alpine and ericaceous species.
Dominant plant species
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eightpetal mountain-avens (Dryas octopetala), shrub
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netleaf willow (Salix reticulata), shrub
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entireleaf mountain-avens (Dryas integrifolia), shrub
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dwarf birch (Betula nana), shrub
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black crowberry (Empetrum nigrum), shrub
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bog blueberry (Vaccinium uliginosum), shrub
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Bigelow's sedge (Carex bigelowii), grass
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bluejoint (Calamagrostis canadensis), grass
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Altai fescue (Festuca altaica), grass
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wideleaf polargrass (Arctagrostis latifolia), grass
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sedge (Carex), grass
Pathway 2.1A
Community 2.1 to 2.2The process that creates nonsorted circles creates communities 2.1 and 2.2 simultaneously. Soil at the center of a circle is frozen and cryoturbated, restricting most vegetation colonization and growth.
Pathway 2.2A
Community 2.2 to 2.1The process that creates nonsorted circles creates communities 2.1 and 2.2 simultaneously. Soil pushed to the edge of the circle generally remains vegetated with the same species found in the reference state.
Transition T1A
State 1 to 2The process that creates nonsorted circles creates communities 2.1 and 2.2 simultaneously. The creation dynamics of nonsorted circles are not fully understood. It is suggested that gaps in the insulation provided by the organic layer allow available water to freeze. Surface and subsurface freezing restrict plant roots and growth, eventually removing vegetation from the center. A ring of vegetation is created as water is pulled into the center of the bare circle (Daanen et al., 2008).
Restoration pathway R2A
State 2 to 1The full cycle of nonsorted circles is poorly understood. It is suggested that if the freeze/thaw process that creates and maintains nonsorted circles ends, then edge vegetation may colonize the circle, reestablishing the reference state across the microfeature.
Additional community tables
Table 10. Community 1.1 plant community composition
Group Common name Symbol Scientific name Annual production () Foliar cover (%) Undefined1 Vascular plants 720–940 Shrub/Vine2 Shrubs 400–500 marsh Labrador tea LEPAD Ledum palustre ssp. decumbens 145–160 – dwarf birch BENA Betula nana 135–150 – bog blueberry VAUL Vaccinium uliginosum 125–135 – mountain alder ALVIC Alnus viridis ssp. crispa 110–120 – tealeaf willow SAPU15 Salix pulchra 90–100 – lingonberry VAVI Vaccinium vitis-idaea 55–60 – Richardson's willow SARI4 Salix richardsonii 9–10 – black crowberry EMNI Empetrum nigrum 8–9 – alpine bearberry ARAL2 Arctostaphylos alpina 0–1 – netleaf willow SARE2 Salix reticulata 1 – small cranberry VAOX Vaccinium oxycoccos 0–1 – Lapland rosebay RHLA2 Rhododendron lapponicum 0–1 – Alaska bog willow SAFU Salix fuscescens 1 – Grass/Grasslike3 Grass/Grasslike 180–230 Bigelow's sedge CABI5 Carex bigelowii 145–160 – tussock cottongrass ERVA4 Eriophorum vaginatum 105–115 – water sedge CAAQ Carex aquatilis 10–11 – cottongrass ERIOP Eriophorum 7–8 – Forb4 Forbs 145–180 cloudberry RUCH Rubus chamaemorus 20 – field horsetail EQAR Equisetum arvense 10–11 – arctic sweet coltsfoot PEFR5 Petasites frigidus 5 – Lichen5 Live lichen biomass 65–610 FLCU Flavocetraria cucullata 6–13 – cup lichen CLADO3 Cladonia 5–11 – greygreen reindeer lichen CLRA60 Cladina rangiferina 5–10 – reindeer lichen CLAR60 Cladina arbuscula 3–7 – reindeer lichen CLMI60 Cladina mitis 3–6 – cup lichen CLGR13 Cladonia gracilis 2–5 – island cetraria lichen CEIS60 Cetraria islandica 2–5 – cup lichen CLAM60 Cladonia amaurocraea 1–2 – Lichen 2LICHN Lichen 1–2 – Moss6 Moss / Clubmoss biomass 940–3020 Table 11. Community 2.1 plant community composition
Group Common name Symbol Scientific name Annual production () Foliar cover (%) Table 12. Community 2.2 plant community composition
Group Common name Symbol Scientific name Annual production () Foliar cover (%) Interpretations
Animal community
This site is distinguished from most other tundra types by the somewhat greater
"structural diversity" of its vegetation; that is, in addition to supporting dwarf shrubs and
herbs common on other tundra sites, taller shrubs - up to 4 ft in height - may grow
scattered across these areas. The presence of taller shrubs may permit some birds and
mammals otherwise not found in similar tundra areas to use this site for cover, perching,
nesting feeding, etc. In addition, taller shrubs may remain accessible above the snow in
winter, thus providing winter, as well as summer, food and possibly cover. As a result,
moose, caribou, willow ptarmigan, and other animals that eat shrubby browse may use
this site year-round. In general, however, wildlife use of this site, like of other tundra
sites, shows tremendous seasonal variation. In summer, this site supports a flurry of
breeding, nesting, feeding, and raising young by small plant- and insect-eating species,
such as lemmings, shrews, voles, sandpipers, longspurs, and arctic hares; as well as by
predators, such as least weasel, red fox, wolverine, rough-legged hawk, snowy owl,
jaeger, etc. intent on feeding their own young. Moose, caribou, muskox, and grizzly
bear may also appear in the summer, feeding on leaves, berries, and other scrubby
browse. By winter, most birds have headed south, shrews and small rodents have moved
underground, and most predators have gone to more productive sites at lower altitudes.
Caribou, muskox, and less commonly moose, may still use this site, however, feeding
on the shrubs protruding above the snow or pawing through the snow for buried lichens.Recreational uses
This site is used for snowmobiling, dogsledding, hunting and trapping (for bear, muskox,
and wolverine), and grayling fishing in nearby streams. Berry picking is the most
important use of this site because of the abundance of berry-producing plants growing
(blueberries, crowberries, low bush cranberries). This site has the potential for
sightseeing and photography since the general area includes canyons, rock formations,
lakes, lavabeds, and hot springs.Wood products
No wood products available from this site.
Other products
Grazing
This site is a good summer range and a fair fall range. Lichen production is low so
would be a poor winter range. This is also a fair spring range as it is one of the first
sites to start greening up and can provide nutritious forage.Other information
These interpretive narratives were developed for USDA reports of range sites on the Seward Peninsula and appear here as written when originally published (SCS, 1984; Swanson et al., 1985).
Supporting information
Inventory data references
Vegetative communities and transitions are described using existing models and expert knowledge. There are no vegetation inventory data points in NASIS associated with this ecological site. External data sources: The Alaska Vegetation Classification (Viereck et al., 1992) LANDFIRE Biophysical Settings Models (LANDFIRE, 2009) Ecological site descriptions of the Seward Peninsula (SCS, 1984). Range survey of the Seward Peninsula reindeer ranges (Swanson et al., 1985)
References
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Viereck, L.A., C. T. Dyrness, A. R. Batten, and K. J. Wenzlick. 1992. The Alaska vegetation classification. U.S. Department of Agriculture, Forest Service, Pacific Northwest Forest and Range Experiment Station General Technical Report PNW-GTR-286..
Other references
Daanen, R.P., D. Misra, H. Epstein, D Walker and V Romanovsky. 2008. Simulating nonsorted circle development in arctic tundra ecosystems. Journal of Geophysical Research. Vol 113, G03S06. Doi: 10.1029/2008JG000682
Kautz, D.R., P. Taber, and S. Nield, editors. 2012. Land Resource Regions and Major Land Resource Areas of Alaska. United States Department of Agriculture, Natural Resources Conservation Service (USDA–NRCS).
LANDFIRE Biophysical Settings. 2009. Biophysical Setting 6816821 – Alaska Arctic Scrub Birch – Ericaceous Shrubland. In: LANDFIRE Biophysical Setting Model: Map zone 68, [Online]. In: Vegetation Dynamics Models. In: LANDFIRE. Washington, DC: U.S. Department of Agriculture, Forest Service, Rocky Mountain Research Station, Fire Sciences Laboratory; U.S. Geological Survey; Arlington, VA: The Nature Conservancy (Producers). Available: https://www.landfire.gov/national_veg_models_op2.php. Accessed Sept 24, 2024
PRISM Climate Group. 2018. “Alaska – average monthly and annual precipitation and minimum, maximum, and mean temperature for the period 1981-2010.” Oregon State University, Corvallis, Oregon. https://prism.oregonstate.edu/projects/alaska.php. Accessed Sept 17, 2024.
Raynolds, M.K., D.A. Walker and H.A Maier. 2006. Alaska Arctic Tundra Vegetation Map. Scale 1:4,000,000. Conservation of Arctic Flora and Fauna (CAFF) Map No. 2, U.S. Fish and Wildlife Service, Anchorage, Alaska.
Scenarios network for Alaska and arctic planning (SNAP). 2014. “Historical Monthly Temperature – 1km, 1901-2009”. http://ckan.snap.uaf.edu/dataset/. Accessed Sept 17, 2024.
Scenarios network for Alaska and arctic planning (SNAP). 2014. “Historical monthly and derived precipitation products downscaled from CRU TS data via the delta methods – 2km, 1901-2009”. http://ckan.snap.uaf.edu/dataset/. Accessed Sept 17, 2024.
Schoeneberger, P.J., and Wysocki, D.A. 2017. Geomorphic Description
System, Version 5.0. Natural Resources Conservation Service, National Soil
Survey Center, Lincoln, NE.
SCS (Soil Conservation Service). 1984. Ecological site descriptions, Seward Peninsula. U.S. Department of Agriculture, Soil Conservation Service, Alaska Field Office, Anchorage.
Soil Survey Staff. 2013. Simplified Guide to Soil Taxonomy. USDA-Natural Resources Conservation Service, National Soil Survey Center, Lincoln, NE.
Swanson, J.D., M. Schuman, and P.C. Scorup. 1985. Range survey of the Seward Peninsula reindeer ranges, Alaska. US Department of Agriculture, Soil Conservation Service.
United States Department of Agriculture, Natural Resources Conservation Service. 2022. Land resource regions and major land resource areas of the United States, the Caribbean, and the Pacific Basin. U.S. Department of Agriculture Handbook 296.
Western Regional Climate Center. 2021. Climate of Alaska. Retrieved from https://wrcc.dri.edu/Climate/narrative_ak.php. Accessed November 15, 2024.
Western Regional Climate Center. 2024. “Kodiak WSO Airport, Alaska ‘Freeze Free’ Season Probabilities.” https://wrcc.dri.edu/cgi-bin/cliTFrezD.pl?akkodi. Accessed Sept 19, 2024.Contributors
Phil Barber
Blaine Spellman
Marji Patz
Steph Schmit
Karin SonnenApproval
Blaine Spellman, 5/29/2025
Acknowledgments
The described soil – ecological site correlations described in this document were reviewed during a February 2024 Provisional Ecological Site workshop in Wasilla, AK. Many thanks are given to the NRCS staff who have provided feedback regarding the MLRA 241X ecological site key and ESDs delivered under the PES national initiative. This ecological site description (ESD) fulfills the requirements of the Provisional Ecological Site (PES) national initiative. This ESD is published to fit current site-soil correlations as they are currently mapped and understood. Further data collection may provide the information to update this ESD from the provisional level to the approved level.
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 10/07/2026 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):
-
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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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.
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