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Ecological site R241XY112AK

Arctic Scrub Frozen Alkaline Loamy Slopes

Last updated: 5/29/2025
Accessed: 10/19/2025

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General information

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:
Dwarf shrub (II.C.2 - level III) / Dwarf birch willow scrub (II.C.2.c – level IV)
(Viereck et al., 1992)

BioPhysical Settings: 6816902 – Alaska Arctic Dwarf Shrubland
(LANDFIRE, 2009)

Seward Rangesites
41 – Shrub meadow (mountain)
(SCS, 1984; Swanson et al., 1985)

Ecological site concept

Ecological Site characteristics:
• Associated with a low scrubland on mountainous, arctic slopes.
• Soils are
• Major vegetative drivers on this site are aquic soil conditions and alkaline soil pH
• Fire is the major disturbance on this site and results in one unique post-fire plant community
• The reference plant community is comprised of low shrub with hydrophytic graminoids, an often-diverse group of forbs, and a mix of insulating mosses and lichens as ground cover
• Solifluction lobes are common periglacial features on the described landform. These are represented by an alternate state.

Associated sites

R241XY110AK	Alpine Dwarf Scrub Gravelly Slopes R241XY110AK is on convex, upslope positions from this ecological site. The prostrate dwarf shrubs are distinct from those in this ecological site.
R241XY111AK	Alpine Sedge-Scrub Frozen Loamy Slopes R241XY111AK describes a sedge-scrubland on alpine footslopes and toeslopes. Soils are acidic.

R241XY110AK

Alpine Dwarf Scrub Gravelly Slopes

R241XY110AK is on convex, upslope positions from this ecological site. The prostrate dwarf shrubs are distinct from those in this ecological site.

R241XY111AK

Alpine Sedge-Scrub Frozen Loamy Slopes

R241XY111AK describes a sedge-scrubland on alpine footslopes and toeslopes. Soils are acidic.

Similar sites

R241XY111AK	Alpine Sedge-Scrub Frozen Loamy Slopes R241XY111AK describes a sedge-scrubland on alpine footslopes and toeslopes. Soils are acidic, unlike the soils of this site that are derived from limestone. The resulting vegetation is different.

R241XY111AK

Alpine Sedge-Scrub Frozen Loamy Slopes

R241XY111AK describes a sedge-scrubland on alpine footslopes and toeslopes. Soils are acidic, unlike the soils of this site that are derived from limestone. The resulting vegetation is different.

Table 1. Dominant plant species

Tree	Not specified
Shrub	(1) Betula nana (2) Vaccinium uliginosum
Herbaceous	(1) Carex bigelowii (2) Carex aquatilis

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Physiographic features

This ecological site occurs on arctic mountain backslopes. Elevation ranges from 500 to 1,000 feet above sea level, though it may extend higher on warm slopes. Slope gradients are nearly level to strongly sloped (0 to 15 percent). This ecological site occurs on all aspects. Ponding occurs on gentle slopes. A shallow to moderately deep water table is present during the growing season.

Solifluction lobes are common periglacial features. These features develop perpendicular to the slope. They may mound several feet along the leading edge. Solifluction lobes have unique site and soil properties that result in a mosaic of vegetation.

Table 2. Representative physiographic features

Slope shape across	(1) Linear
Slope shape up-down	(1) Linear
Hillslope profile	(1) Backslope
Landforms	(1) Mountains > Mountain slope (2) Mountains > Mountain (3) Mountains > Mountain slope > Solifluction lobe
Runoff class	Negligible to medium
Flooding frequency	None
Ponding duration	Brief (2 to 7 days)
Ponding frequency	Occasional
Elevation	500 – 1,000 ft
Slope	15%
Ponding depth	12 in
Water table depth	10 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	Not specified
Ponding frequency	Not specified
Elevation	100 – 2,000 ft
Slope	20%
Ponding depth	Not specified
Water table depth	Not specified

Climatic features

The Arctic climate of this ecological site includes short, cool growing seasons and long, cold winters. Mean annual temperature at sea level is about 22 degrees Fahrenheit in the coastal village of Wales. 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)	60-90 days
Freeze-free period (characteristic range)	50-80 days
Precipitation total (characteristic range)	14-16 in
Frost-free period (actual range)	50-90 days
Freeze-free period (actual range)	40-80 days
Precipitation total (actual range)	10-18 in
Frost-free period (average)	75 days
Freeze-free period (average)	65 days
Precipitation total (average)	15 in

Characteristic range

Actual range

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Figure 1. Monthly precipitation range

Characteristic range

Actual range

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Figure 2. Monthly minimum temperature range

Characteristic range

Actual range

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Figure 3. Monthly maximum temperature range

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Figure 4. Monthly average minimum and maximum temperature

Figure 5. Annual precipitation pattern

Figure 6. Annual average temperature pattern

Influencing water features

This ecological site is influenced by slope discharge. Surface drainages are rare. Water inflow is from upslope precipitation and snow melt, as well as seasonal frost melt during the growing season.

Wetland description

This ecological site may be broadly classified as a slope wetland and further characterized as a rich fen extensive peatland under the Hydrogeomorphic (HGM) classification system (Brinson, 1993; USDA-NRCS, 2008). Soil pH is neutral or alkaline. Subsurface water flow and seasonal melt contribute to soil saturation (Brinson, 1993).

Soil features

Soils are wet Gelisols (Soil Survey Staff, 2013). Permafrost is moderately deep. There is a six-inch organic cap. Permafrost perches water, creating aquic conditions in the soil. Surface rock fragments are absent. Soil pH is slightly to moderately alkaline.

Soils in the alternate state are a mix of Gelisols and Mollisols. Solifluction lobes have unique soil properties distinct from the reference state. Mollisols are common where organics have been pushed together built up along the leading lobe edge. The top and leading edges of lobes can be well drained, while the soil at the base of the leading edge is wet.

Table 5. Representative soil features

Parent material	(1) Colluvium – limestone (2) Organic material
Surface texture	(1) Peat
Drainage class	Poorly drained
Permeability class	Moderate
Depth to restrictive layer	20 – 33 in
Soil depth	60 in
Surface fragment cover <=3"	Not specified
Surface fragment cover >3"	Not specified
Available water capacity (0-40in)	4.1 – 7.2 in
Soil reaction (1:1 water) (0-10in)	7.4 – 8.4
Subsurface fragment volume <=3" (0-60in)	6 – 14%
Subsurface fragment volume >3" (0-60in)	8 – 20%

Ecological dynamics

The Seward Peninsula Highlands (MLRA 241X) is in the arctic where the harsh climate limits the composition and structure of plant communities. This area has cool, short summers and long, cold winters. Limited warmth during the short growing season inhibits trees from occurring. Ordinarily, cold temperatures limit the vertical structure of shrubs and other functional groups (Raynolds et al., 2006).

The low scrub reference plant community is shaped by factors including mean annual air temperature and alkaline soil.

Site and soil conditions support a low scrubland in the reference plant community (Viereck et al., 1992). Cool temperatures and a short growing season support slow growing, often evergreen shrubs. Average shrub height is taller here than in shrubs in more exposed, convex slopes. Limestone colluvial parent material causes soil pH to be slightly to moderately alkaline. Plant diversity, particularly among forbs, is higher here than in similar communities associated with acidic soils (Landfire, 2009).

Fire

Post-fire studies in the Arctic are lacking (Landfire, 2009). However, this community likely burns. Soils are generally wet. However, like tussock tundra, this ecological site produces an adequate fuel load on steeper slopes to be susceptible to lightning strikes during the dry months. It may also burn if neighboring vegetation catches fire first.
The post-fire community depends on fire severity and frequency. Burned locations generally support a mix of fast-growing herbaceous species along with extant shrubs. A severe burn may lower permafrost, allowing deeper-rooting shrubs such as willow to colonize. As a site stabilizes and the organic horizon redevelops, permafrost returns, and the vegetative composition will return to that of the reference plant community.

Alternate State

One alternate state is recognized in this ecological site. Solifluction lobes are a type of patterned ground. These linear features develop perpendicular to the slope direction. Solifluction formation leads to a distinct mosaic of vegetation.

Solifluction lobes have distinct plant communities associated with different positions. The first plant community (2.1) occurs on the top and leading edge of the lobe. Soils are drier and have more organic in the subsurface horizons. This community contains less hydrophytic species than community 1.1. The second community is at the base of the leading edge. This area is typically concave and ponds water. Hydrophytic species are the dominant plant type.

The information in this Ecological Dynamics section, including the state-and-transition model (STM), was developed based on professional experience and a review of available 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 text

Ecosystem states

1. Reference State

2. Solifluction Lobes

T1A	-	Solifluction lobe formation
R2A	-	Solifluction lobe degradation

State 1 submodel, plant communities

1.1. Betula nana - Vaccinium uliginosum / Carex bigelowii - Carex aquatilis

1.2. Carex spp. / Chamerion angustifolium

1.1A	-	Fire
1.2A	-	Fire recovery

State 2 submodel, plant communities

2.1. Betula nana - Vaccinium uliginosum / Carex bigelowii

2.2. Salix pulchra / Carex bigelowii - Carex aquatilis

2.1A	-	Solifluction lobe movement
2.2A	-	Solifluction lobe movement

State 1
Reference State

This reference state is developed and characterized using available vegetation models, most notably United States Department of Agriculture - Soil Conservation Service range surveys from the 1980s (SCS, 1984; Swanson et al., 1985). The reference state describes two distinct vegetative communities. One post-burn community is recognized. Exposure to wind and low annual temperatures restrict vegetation height. 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

dwarf birch (Betula nana), shrub
bog blueberry (Vaccinium uliginosum), shrub
entireleaf mountain-avens (Dryas integrifolia), shrub
tealeaf willow (Salix pulchra), shrub
netleaf willow (Salix reticulata), shrub
sedge (Carex), grass
field horsetail (Equisetum arvense), other herbaceous
arctic sweet coltsfoot (Petasites frigidus), other herbaceous

Community 1.1
Betula nana - Vaccinium uliginosum / Carex bigelowii - Carex aquatilis

This community is an open low scrubland (Viereck et al., 1992). The major plant groups are low shrubs, dwarf shrubs, and medium graminoids (Swanson et al., 1985). Plant height is restricted by wind exposure. This community is primarily comprised of ericaceous shrubs, though some alpine indicator species (Dryas spp., Loiseleuria procumbens) may be present. Open areas support mostly mosses. Ground cover often also contains lichens, herbaceous litter, and some surface rock fragments. 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

dwarf birch (Betula nana), shrub
bog blueberry (Vaccinium uliginosum), shrub
entireleaf mountain-avens (Dryas integrifolia), shrub
tealeaf willow (Salix pulchra), shrub
netleaf willow (Salix reticulata), shrub
black crowberry (Empetrum nigrum), shrub
marsh Labrador tea (Ledum palustre ssp. decumbens), shrub
Bigelow's sedge (Carex bigelowii), grass
water sedge (Carex aquatilis), grass
field horsetail (Equisetum arvense), other herbaceous
arctic sweet coltsfoot (Petasites frigidus), other herbaceous
cloudberry (Rubus chamaemorus), other herbaceous

Figure 7. Annual production by plant type (representative values) or group (midpoint values)

Table 6. Annual production by plant type

Plant type	Low (lb/acre)	Representative value (lb/acre)	High (lb/acre)
Moss	800	2040	4000
Shrub/Vine	315	340	360
Grass/Grasslike	200	215	230
Lichen	100	150	200
Forb	55	60	65
Total	1470	2805	4855

Table 7. Ground cover

Tree foliar cover	0%
Shrub/vine/liana foliar cover	25-50%
Grass/grasslike foliar cover	12-25%
Forb foliar cover	6-12%
Non-vascular plants	35-75%
Biological crusts	0%
Litter	12-25%
Surface fragments >0.25" and <=3"	0%
Surface fragments >3"	0-6%
Bedrock	0%
Water	0-6%
Bare ground	0-6%

Community 1.2
Carex spp. / Chamerion angustifolium

This community is a mesic forb herbaceous meadow (Viereck et al., 1992). The major plant groups are medium graminoids, medium forbs, and mosses (Landfire, 2009). Species composition of this post-fire community will vary based on pre-fire site conditions and fire severity. Generally, the community will support sedges and mosses, as well as fast-growing colonizing species such as fireweed. Surviving individuals of extant shrubs may be present.

Dominant plant species

sedge (Carex), grass
bluejoint (Calamagrostis canadensis), grass
fireweed (Chamerion angustifolium), other herbaceous

Pathway 1.1A
Community 1.1 to 1.2

Fire dynamics on this ecological site are poorly understood (Landfire, 2009). Fire severity and frequency have a direct impact on post-fire vegetative composition. A low severity fire may only burn susceptible above ground plant biomass. A severe fire will destroy above surface biomass and part or all of the organic horizon as well as rootstock. The fire return interval is unknown, but may match that of similarly located tussock tundra, at between 30 - 600+ years.

Pathway 1.2A
Community 1.2 to 1.1

Fire dynamics on this ecological site are poorly understood (Landfire, 2009). This community is generally short-lived (1 to 19 years) (Landfire, 2009). Community 1.2 is quickly colonized by shrubs from the seedstock or from nearby seed sources.

State 2
Solifluction Lobes

The reference state describes solifluction lobe features. There are two distinct vegetative communities on this feature. Exposure to wind and low annual temperatures restrict vegetation height.

Dominant plant species

dwarf birch (Betula nana), shrub
bog blueberry (Vaccinium uliginosum), shrub
black crowberry (Empetrum nigrum), shrub
sedge (Carex), grass

Community 2.1
Betula nana - Vaccinium uliginosum / Carex bigelowii

This community is a closed low scrubland (Viereck et al., 1992). The major plant groups are low shrubs, dwarf shrubs, and medium graminoids (Swanson et al., 1985). Plant height is restricted by wind exposure.

Dominant plant species

dwarf birch (Betula nana), shrub
bog blueberry (Vaccinium uliginosum), shrub
tealeaf willow (Salix pulchra), shrub
black crowberry (Empetrum nigrum), shrub
marsh Labrador tea (Ledum palustre ssp. decumbens), shrub
Bigelow's sedge (Carex bigelowii), grass
field horsetail (Equisetum arvense), other herbaceous
cloudberry (Rubus chamaemorus), other herbaceous

Community 2.2
Salix pulchra / Carex bigelowii - Carex aquatilis

This community is in the concavity beneath the leading edge of the solifluction lobe. Soils are wet and ponded, which is reflected in the hydrophytic vegetation. Common plant groups include low shrubs, medium graminoids, and medium forbs. Ground cover may be comprised of a mix of Sphagnum mosses and water.

Dominant plant species

tealeaf willow (Salix pulchra), shrub
water sedge (Carex aquatilis), grass
arctic sweet coltsfoot (Petasites frigidus), other herbaceous

Pathway 2.1A
Community 2.1 to 2.2

Solifluction lobe movement

Pathway 2.2A
Community 2.2 to 2.1

Solifluction lobe movement

Transition T1A
State 1 to 2

Solifluction lobes are created by the downward slide of soil and overlying vegetation atop a substrate of permafrost and seasonal melt.

Restoration pathway R2A
State 2 to 1

Solifluction lobe degradation occurs with the natural movement that creates the solifluction lobe.

Additional community tables

Table 8. Community 1.1 plant community composition

Group	Common name	Symbol	Scientific name	Annual production (lb/acre)	Foliar cover (%)
Undefined
1	Vascular plants			570–660
Shrub/Vine
2	Shrubs			315–360
	dwarf birch	BENA	Betula nana	55–60	–
	bog blueberry	VAUL	Vaccinium uliginosum	50–60	–
	entireleaf mountain-avens	DRIN4	Dryas integrifolia	45–50	–
	tealeaf willow	SAPU15	Salix pulchra	35–40	–
	netleaf willow	SARE2	Salix reticulata	30–40	–
	Alaska bog willow	SAFU	Salix fuscescens	15–20	–
	black crowberry	EMNI	Empetrum nigrum	15–20	–
	marsh Labrador tea	LEPAD	Ledum palustre ssp. decumbens	15	–
	alpine azalea	LOPR	Loiseleuria procumbens	15	–
	lingonberry	VAVI	Vaccinium vitis-idaea	15	–
	arctic willow	SAAR27	Salix arctica	10	–
	red fruit bearberry	ARRU	Arctostaphylos rubra	6–7	–
	Chamisso's willow	SACH	Salix chamissonis	4–5	–
	eightpetal mountain-avens	DROC	Dryas octopetala	2–3	–
	grayleaf willow	SAGL	Salix glauca	2	–
	white arctic mountain heather	CATE11	Cassiope tetragona	2	–
	alpine bearberry	ARAL2	Arctostaphylos alpina	1	–
Grass/Grasslike
3	Grass/Grasslike			200–230
	Bigelow's sedge	CABI5	Carex bigelowii	150–175	–
	water sedge	CAAQ	Carex aquatilis	30–40	–
	bluegrass	POA	Poa	5	–
	wideleaf polargrass	ARLA2	Arctagrostis latifolia	3–4	–
	sheathed sedge	CAVA2	Carex vaginata	3–4	–
	spike sedge	CANA2	Carex nardina	2	–
	round sedge	CARO7	Carex rotundata	1	–
	red cottongrass	ERRU2	Eriophorum russeolum	1	–
	tussock cottongrass	ERVA4	Eriophorum vaginatum	1	–
	bluejoint	CACA4	Calamagrostis canadensis	1	–
	sedge	CAREX	Carex	1	–
	threadleaf sedge	CAFI	Carex filifolia	1	–
Forb
4	Forb			55–65
	cloudberry	RUCH	Rubus chamaemorus	15–20	–
	field horsetail	EQAR	Equisetum arvense	7–9	–
	wintergreen	PYROL	Pyrola	5–6	–
	tall Jacob's-ladder	POAC	Polemonium acutiflorum	3–4	–
	arctic sweet coltsfoot	PEFR5	Petasites frigidus	3	–
	twoflower cinquefoil	POBI8	Potentilla biflora	2	–
	marsh horsetail	EQPA	Equisetum palustre	2	–
	tall bluebells	MEPA	Mertensia paniculata	0–1	–
	lousewort	PEDIC	Pedicularis	1	–
	capitate lousewort	PECA2	Pedicularis capitata	1	–
	Labrador lousewort	PELA	Pedicularis labradorica	0–1	–
	larkspurleaf monkshood	ACDE2	Aconitum delphiniifolium	1	–
	nodding arnica	ARLE2	Arnica lessingii	0–1	–
	boreal sagebrush	ARAR9	Artemisia arctica	1	–
	draba	DRABA	Draba	0–1	–
	alpine bistort	POVI3	Polygonum viviparum	1	–
	liverleaf wintergreen	PYAS	Pyrola asarifolia	1	–
	sidebells wintergreen	ORSE	Orthilia secunda	0–1	–
	buttercup	RANUN	Ranunculus	1	–
	arctic raspberry	RUAR	Rubus arcticus	0–1	–
	narrowleaf saw-wort	SAAN3	Saussurea angustifolia	1	–
	nutty saw-wort	SANU	Saussurea nuda	1	–
	heartleaf saxifrage	SANEN	Saxifraga nelsoniana ssp. nelsoniana	1	–
	captiate valerian	VACA3	Valeriana capitata	1	–
	Forb (herbaceous, not grass nor grass-like)	2FORB	Forb (herbaceous, not grass nor grass-like)	1	–
Lichen
5	Live lichen biomass			100–200
		FLCU	Flavocetraria cucullata	40–80	–
	island cetraria lichen	CEIS60	Cetraria islandica	30–60	–
	greygreen reindeer lichen	CLRA60	Cladina rangiferina	15–25	–
	reindeer lichen	CLAR60	Cladina arbuscula	9–19	–
	cup lichen	CLADO3	Cladonia	3–7	–
	cup lichen	CLGR13	Cladonia gracilis	3–6	–
	Lichen	2LICHN	Lichen	0–1	–
	witch's hair lichen	ALOC60	Alectoria ochroleuca	1	–
Moss
6	Moss / Clubmoss biomass			800–4000

Interpretations

Animal community

This site supports a variety of wildlife species adapted to take advantage of foods that
appear only briefly, but often in great abundance. Grizzly bear, and to a lesser extent
black bear, arrive first in spring to feed on emerging sedges, grasses, and forbs, and
return again in fall to gorge themselves on ripening berries. In spring, arctic ground
squirrels and, near rocky cover, hoary marmots end their hibernations and begin their
brief season of breeding, raising young, and putting on fat for the winter. Voles, and
other small mammals active all winter in the relative warmth of underground burrows,
nests, and runways, emerge to feed, breed and store "hay" for the winter. They provide
prey for the raptors, foxes, wolverines, and other predators that arrive to take advantage
of the seasonal flurry of small mammal activity. Migratory birds adapted to breed here,
hardy species like the seed-eating common redpoll and the insectivorous water pipit and
lapland longspur, arrive for their brief nesting season. During the summer, these high
shrub meadows are also favored by moose, who feed particularly on the abundant dwarf
arctic birch and willows, as well as sedges and forbs. As winter approaches, many of
these birds and mammals move to lower elevations or latitudes to escape the harsh
mountain winter, or like the ground squirrel and marmot, withdraw to winter dens to
hibernate. Then only a few small mammals remain active beneath the snow, feeding on
stored plant matter and buried parts of herbs and shrubs.

Recreational uses

Aesthetically this site provides the photographer or sightseer with a picturesque
landscape. This site can be used for snowmobiling, dogsledding, hunting (ptarmigan,
caribou, and bear), trapping (red fox), and fishing in nearby streams. This site can
produce an ample supply of blueberries for the berry picker and if near streams, gold
panning for the enthusiast. Hot mineral springs may also be found on this site.

Wood products

No wood products available from this site.

Other products

Grazing

This site is a poor spring range and a fair summer and fall range. Diamond leaf willow
(Salix planifolia) dwarf arctic birch (Betula nana), and sedges can provide high value forage during these seasons.

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

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

Brinson, M.M. 1993. A hydrogeomorphic classification for wetlands. Wetlands Research Program, US Army Corp of Engineers. Technical Report WRP-DE-4.

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 6816902 – Alaska Arctic Dwarf 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.

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.

United States Department of Agriculture, Natural Resources Conservation Service. 2008. Hydrogeomorphic Wetland Classification System: an overview and modification to better meet the needs of the Natural Resources Conservation Service. Technical Note No 190-8-76.

Western Regional Climate Center. 2021. Climate of Alaska. Retrieved from https://wrcc.dri.edu/Climate/narrative_ak.php. Accessed November 15, 2024.

Contributors

Phil Barber
Blaine Spellman
Marji Patz
Steph Schmit
Karin Sonnen

Approval

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	05/31/2025
Approved by	Blaine Spellman
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: