Natural Resources
Conservation Service

Ecological site R241XY160AK

Arctic Scrub Riparian Complex

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

Home / Esd catalog / MLRA 241X / Ecological site R241XY160AK

USC

Metric

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:
Closed tall scrub (II.B.1 - level III) / Willow (II.B.1.a – level IV)
(Viereck et al., 1992)

BioPhysical Settings: 6817150 – Alaska Arctic Floodplain
(LANDFIRE biophysical settings, 2009)

Seward Rangesites
20 – Tall Shrub flood plain
(SCS, 1984; Swanson et al., 1985)

Ecological site concept

Ecological Site characteristics:
• Describes the riparian complex of vegetative communities along the flood plain gradient
• Flooding is the major disturbance associated with this ecological site
• Rarely flooded areas like high floodplains have siltier soil profiles that are wet and frozen. Frequently flooded areas like point bars and low floodplains have comparatively much more sandy and gravelly soils that are dry and unfrozen.
• The reference plant community is a mixed willow and alder scrubland with forbs and graminoids in the understory. Flood regime results in two plant communities within the reference state.

Associated sites

R241XY163AK	Arctic Scrub-Tussock Silty Stream Terrace R241XY163AK describes scrub-tussock tundra terraces. Soils are very poorly drained and are susceptible to ponding during the growing season.

R241XY163AK

Arctic Scrub-Tussock Silty Stream Terrace

R241XY163AK describes scrub-tussock tundra terraces. Soils are very poorly drained and are susceptible to ponding during the growing season.

Similar sites

R241XY163AK	Arctic Scrub-Tussock Silty Stream Terrace Community 1.2 in this ecological site is similar to R241XY163AK. Both are in river valleys. Terrace sites do not undergo flooding and generally support wetter, permafrost-rich soils which is reflected in the vegetation.
R241XY118AK	Arctic Tall Scrub Loamy Slopes Ecological site R241XY118AK describes willow scrubland on mesic to wet mountain backslopes. The vegetation is similar, but the underlying soils and prospective management for each site are different.

R241XY163AK

Arctic Scrub-Tussock Silty Stream Terrace

Community 1.2 in this ecological site is similar to R241XY163AK. Both are in river valleys. Terrace sites do not undergo flooding and generally support wetter, permafrost-rich soils which is reflected in the vegetation.

R241XY118AK

Arctic Tall Scrub Loamy Slopes

Ecological site R241XY118AK describes willow scrubland on mesic to wet mountain backslopes. The vegetation is similar, but the underlying soils and prospective management for each site are different.

Table 1. Dominant plant species

Tree	Not specified
Shrub	(1) Alnus (2) Salix pulchra
Herbaceous	(1) Calamagrostis canadensis (2) Equisetum arvense

Download full description

Physiographic features

This ecological site occurs on river valley flood plains. Elevation ranges from 10 to 700 feet above sea level. Slope gradients are nearly level (0 to 2 percent), and this site occurs on all aspects. Areas proximal to the river flood more frequently and with greater energy than distal locations. Ponding does not occur. A shallow to moderately deep water table is present during the growing season along a gradient from areas proximal to distal from the flood source.

Table 2. Representative physiographic features

Slope shape across	(1) Linear
Slope shape up-down	(1) Linear
Landforms	(1) River valley > Flood plain (2) River valley > Flood plain (3) River valley > Flood plain (4) River valley > Flood plain
Runoff class	Negligible to very low
Flooding duration	Brief (2 to 7 days)
Flooding frequency	Occasional to frequent
Ponding frequency	None
Elevation	10 – 700 ft
Slope	2%
Water table depth	20 in
Aspect	W, NW, N, NE, E, SE, S, SW

Table 3. Representative physiographic features (actual ranges)

Runoff class	Not specified
Flooding duration	Not specified
Flooding frequency	None to frequent
Ponding frequency	Not specified
Elevation	Not specified
Slope	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

Bar

Line

Figure 1. Monthly precipitation range

Characteristic range

Actual range

Bar

Line

Figure 2. Monthly minimum temperature range

Characteristic range

Actual range

Bar

Line

Figure 3. Monthly maximum temperature range

Bar

Line

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 riparian water features. Precipitation and seasonal snow melt are the main sources of water. This site is usually unbraided but may braid in high energy locations.

Wetland description

This ecological site is classified as a riverine wetland under the Hydrogeomorphic (HGM) classification system (Brinson, 1993; USDA-NRCS 2008). In the associated flood plains, overbank flow from the channel and subsurface hydraulic connections between the stream and adjacent wetlands are the main sources of water (Brinson, 1993).

Depth to the water table may decrease during peak snow melt and following summer storm events and increase during extended dry periods.

Soil features

Soils formed in stratified sandy, silty and gravelly alluvium. Rock fragments on the soil surface are common though often in low amounts. These are mineral soils without an organic cap. The surface mineral horizon typically has minimal rock fragments. Soils are very deep. High floodplains and similar areas with less frequent flooding have permafrost at shallow to moderate depth. Point bars and low floodplains with more frequent flooding lack permafrost in the soil profile. Soil pH is slightly acidic to neutral. Soil wetness varies by time of year and location, and drainage likewise ranges from moderately well drained to poorly drained, often depending on the presence of permafrost.

Table 5. Representative soil features

Parent material	(1) Alluvium (2) Organic material (3) Alluvium
Surface texture	(1) Mucky fine sandy loam (2) Silt loam (3) Sandy loam
Drainage class	Poorly drained to moderately well drained
Permeability class	Moderate to moderately rapid
Depth to restrictive layer	9 – 33 in
Soil depth	60 in
Surface fragment cover <=3"	5%
Surface fragment cover >3"	10%
Available water capacity (0-40in)	5.9 – 7.1 in
Soil reaction (1:1 water) (0-40in)	6.1 – 7.2
Subsurface fragment volume <=3" (0-60in)	5%
Subsurface fragment volume >3" (0-60in)	5%

Table 6. Representative soil features (actual values)

Drainage class	Not specified
Permeability class	Not specified
Depth to restrictive layer	1 – 35 in
Soil depth	60 in
Surface fragment cover <=3"	5%
Surface fragment cover >3"	10%
Available water capacity (0-40in)	Not specified
Soil reaction (1:1 water) (0-40in)	Not specified
Subsurface fragment volume <=3" (0-60in)	53%
Subsurface fragment volume >3" (0-60in)	29%

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. Both lowland and upland landscapes are a mix of shrubs, graminoids, forbs, mosses, and lichens. Cold temperatures limit the vertical structure of shrubs and other functional groups (Raynolds et al., 2006). The exception is microclimates where accumulated snow protects vegetation from harsh winds and insulates soils. These microclimates allow for shrubs to grow much taller and occur on landforms such as flood plains.

This ecological site describes the floodplain riparian complex. Local site factors such as relative site elevation, soil characteristics, and flood energy support two communities. The reference plant community is a willow scrubland. Areas that undergo high energy flooding are typically proximal to the flood source. These areas typically support community 1.1. Community 1.2 typically develops in areas away from the flood source, where permafrost is nearer the surface.

Spatial and temporal patterns in soil and site hydrology create two flood plain communities. Depth to permafrost greatly influences vegetation. The presence of water close to a flood source supports unfrozen talik. Additionally, a high volume of subsurface rock fragments, which transfer and store heat in the soil, is also prohibitive towards permafrost. Both conditions are common in community 1.1.

River channel migration across this site is a major disturbance (Landfire, 2009). This action affects site hydrology and can shift one community to the another. This change is generally slow. Channel movement cuts and erodes existing banks while simultaneously depositing sediments on new bars.

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

State 1 submodel, plant communities

1.1. Salix pulchra - Salix alaxensis - Alnus spp. / Calamagrostis canadensis

1.2. Salix pulchra - Betula spp. / Carex bigelowii

1.1A	-	Increase in flood energy
1.2A	-	Decrease in flooding energy, decrease in depth to permafrost

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 (SCS, 1984; Swanson et al., 1985). The reference state describes two distinct vegetative communities across the flood plain complex. Flooding energy and depth to permafrost appear to be the major factors influencing vegetation, though other factors may be of concern.

Dominant plant species

tealeaf willow (Salix pulchra), shrub
feltleaf willow (Salix alaxensis), shrub
grayleaf willow (Salix glauca), shrub
mountain alder (Alnus viridis ssp. crispa), shrub
bluejoint (Calamagrostis canadensis), grass
field horsetail (Equisetum arvense), other herbaceous
tall bluebells (Mertensia paniculata), other herbaceous

Community 1.1
Salix pulchra - Salix alaxensis - Alnus spp. / Calamagrostis canadensis

This community is a tall shrub scrubland (Viereck et al., 1992). The major plant groups are tall shrubs, medium shrubs, tall graminoids, and medium forbs (Swanson et al., 1985). This community supports a mix of alder and willow species in the canopy. The shaded understory is comprised of bluejoint, horsetails, mosses, and lichens. Ground cover is predominantly herbaceous litter but also contains mosses and lichens. 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. Lichen and moss biomass data below refers to total biomass, while vascular plants biomass refers to annual production.

Dominant plant species

tealeaf willow (Salix pulchra), shrub
feltleaf willow (Salix alaxensis), shrub
grayleaf willow (Salix glauca), shrub
mountain alder (Alnus viridis ssp. crispa), shrub
bluejoint (Calamagrostis canadensis), grass
field horsetail (Equisetum arvense), other herbaceous
tall bluebells (Mertensia paniculata), 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)
Shrub/Vine	2060	2500	2930
Moss	1400	1490	1665
Grass/Grasslike	115	140	160
Forb	115	140	160
Lichen	0	5	10
Total	3690	4275	4925

Table 8. Soil surface cover

Tree basal cover	0%
Shrub/vine/liana basal cover	25-50%
Grass/grasslike basal cover	6-12%
Forb basal cover	12-25%
Non-vascular plants	6-18%
Biological crusts	0%
Litter	50-75%
Surface fragments >0.25" and <=3"	0%
Surface fragments >3"	0%
Bedrock	0%
Water	0%
Bare ground	0%

Community 1.2
Salix pulchra - Betula spp. / Carex bigelowii

This community is a low shrub scrubland (Viereck et al., 1992). The major plant groups are low shrubs, medium shrubs, tall graminoids, and medium forbs (Swanson et al., 1985). This community supports a mix of willow and ericaceous species in the canopy. Open areas and the understory include bluejoint, horsetails, mosses, and lichens. Ground cover is predominantly herbaceous litter but also contains mosses and lichens.

Dominant plant species

tealeaf willow (Salix pulchra), shrub
willow (Salix), shrub
Bigelow's sedge (Carex bigelowii), grass
sedge (Carex), grass
bluejoint (Calamagrostis canadensis), grass
water sedge (Carex aquatilis), grass
field horsetail (Equisetum arvense), other herbaceous
tall bluebells (Mertensia paniculata), other herbaceous
northern bedstraw (Galium boreale), other herbaceous

Figure 8. Annual production by plant type (representative values) or group (midpoint values)

Table 9. Soil surface cover

Tree basal cover	0%
Shrub/vine/liana basal cover	12-25%
Grass/grasslike basal cover	12-25%
Forb basal cover	6-12%
Non-vascular plants	12-30%
Biological crusts	0%
Litter	12-25%
Surface fragments >0.25" and <=3"	0%
Surface fragments >3"	0%
Bedrock	0%
Water	0%
Bare ground	0-6%

Pathway 1.1A
Community 1.1 to 1.2

Flooding is the major disturbance in this ecological site. It is a frequent occurrence in community 1.1. A talik of unfrozen soil is supported by the continual presence of unfrozen water that occurs near rivers. When flooding energy decreases due to decreased flow or a shift in the river channel, the organic mat thickens. This causes permafrost to form or rise in the soil profile. Soil becomes more poorly drained and permafrost becomes a root-restrictive layer (SCS, 1984).

Pathway 1.2A
Community 1.2 to 1.1

Flooding is the major disturbance in this ecological site. Flooding is responsible for determining the depth to permafrost, which influences the vegetative community. Deeper rooting willows are able to colonize. Additionally, scouring creates opportunities for seed dispersal and colonization. Fast growing herbaceous species flourish.

Additional community tables

Table 10. Community 1.1 plant community composition

Group	Common name	Symbol	Scientific name	Annual production (lb/acre)	Foliar cover (%)
Undefined
1	Vascular Plants			2290–3260
Shrub/Vine
2	Shrub			2060–2930
	tealeaf willow	SAPU15	Salix pulchra	540–770	–
	feltleaf willow	SAAL	Salix alaxensis	535–765	–
	mountain alder	ALVIC	Alnus viridis ssp. crispa	290–415	–
	Richardson's willow	SARI4	Salix richardsonii	260–370	–
	grayleaf willow	SAGL	Salix glauca	215–305	–
	bog blueberry	VAUL	Vaccinium uliginosum	55–80	–
	shrubby cinquefoil	DAFR6	Dasiphora fruticosa	35–50	–
	red fruit bearberry	ARRU	Arctostaphylos rubra	15–25	–
	dwarf birch	BENA	Betula nana	7–10	–
	littletree willow	SAAR3	Salix arbusculoides	5–7	–
	blueberry willow	SAMY	Salix myrtillifolia	5–7	–
	halberd willow	SAHA	Salix hastata	2–3	–
	Alaska bog willow	SAFU	Salix fuscescens	2–3	–
	Shrub (>.5m)	2SHRUB	Shrub (>.5m)	2–3	–
	beauverd spirea	SPST3	Spiraea stevenii	2–3	–
	prickly rose	ROAC	Rosa acicularis	0–1	–
	black crowberry	EMNI	Empetrum nigrum	0–1	–
	marsh Labrador tea	LEPAD	Ledum palustre ssp. decumbens	0–1	–
	lingonberry	VAVI	Vaccinium vitis-idaea	0–1	–
	russet buffaloberry	SHCA	Shepherdia canadensis	0–1	–
Grass/Grasslike
3	Grass/Grasslike			115–160
	bluejoint	CACA4	Calamagrostis canadensis	135–195	–
	wideleaf polargrass	ARLA2	Arctagrostis latifolia	15–25	–
	water sedge	CAAQ	Carex aquatilis	2–3	–
	Bigelow's sedge	CABI5	Carex bigelowii	2–3	–
	Ramensk's sedge	CARA4	Carex ramenskii	2–3	–
	Altai fescue	FEAL	Festuca altaica	2–3	–
	bluegrass	POA	Poa	2–3	–
	red fescue	FERU2	Festuca rubra	0–1	–
	alpine sweetgrass	ANMOA3	Anthoxanthum monticola ssp. alpinum	0–1	–
	Pumpelly's brome	BRINP5	Bromus inermis ssp. pumpellianus var. pumpellianus	0–1	–
Forb
4	Forb			115–160
	field horsetail	EQAR	Equisetum arvense	65–95	–
	northern bedstraw	GABO2	Galium boreale	20–25	–
	tall bluebells	MEPA	Mertensia paniculata	20–25	–
	arctic sweet coltsfoot	PEFR5	Petasites frigidus	9–13	–
	arctic raspberry	RUAR	Rubus arcticus	9–13	–
	cloudberry	RUCH	Rubus chamaemorus	9–13	–
	tall Jacob's-ladder	POAC	Polemonium acutiflorum	5–7	–
	largeflowered wintergreen	PYGR	Pyrola grandiflora	2–3	–
	buttercup	RANUN	Ranunculus	2–3	–
	alpine sweetvetch	HEAL	Hedysarum alpinum	2–3	–
	Rocky Mountain goldenrod	SOMU	Solidago multiradiata	2–3	–
	arctic starflower	TREU	Trientalis europaea	2–3	–
	fireweed	CHAN9	Chamerion angustifolium	2–3	–
	dwarf fireweed	CHLA13	Chamerion latifolium	0–1	–
	gentian	GENTI	Gentiana	0–1	–
	scouringrush horsetail	EQHY	Equisetum hyemale	0–1	–
	variegated scouringrush	EQVA	Equisetum variegatum	0–1	–
	larkspurleaf monkshood	ACDE2	Aconitum delphiniifolium	0–1	–
	seacoast angelica	ANLU	Angelica lucida	0–1	–
	Tilesius' wormwood	ARTI	Artemisia tilesii	0–1	–
	arctic aster	EUSI13	Eurybia sibirica	0–1	–
	daisy	CHRYS2	Chrysanthemum	0–1	–
	captiate valerian	VACA3	Valeriana capitata	0–1	–
	Forb (herbaceous, not grass nor grass-like)	2FORB	Forb (herbaceous, not grass nor grass-like)	0–1	–
	starwort	STELL	Stellaria	0–1	–
	fleshy starwort	STCR	Stellaria crassifolia	0–1	–
	heartleaf saxifrage	SANEN	Saxifraga nelsoniana ssp. nelsoniana	0–1	–
	roseroot stonecrop	RHRO3	Rhodiola rosea	0–1	–
	ragwort	SENEC	Senecio	0–1	–
	beachhead iris	IRSE	Iris setosa	0–1	–
	Jacob's-ladder	POLEM	Polemonium	0–1	–
	alpine bistort	POVI3	Polygonum viviparum	0–1	–
	purple marshlocks	COPA28	Comarum palustre	0–1	–
Lichen
5	Live lichen biomass			0–10
	cetraria lichen	CETRA2	Cetraria	0–10	–
Moss
6	Moss/Clubmoss biomass			1400–1665

Table 11. Community 1.1 forest understory composition

Common name	Symbol	Scientific name	Nativity	Height (ft)	Canopy cover (%)

Interpretations

Animal community

Tall shrub sites in floodplains can be of high value to wildlife, particularly if they are
dominated by willow species. Five attributes enhance the potential wildlife values of this
site: 1) floodplain soils tend to be well-drained, and may be enriched by deposits from
periodic flooding: 2) the lower elevations at which this site occurs tend to experience
relatively lower snowfalls and milder climates than upland sites; 3) proximity of open
water is important to many wildlife species; 4) tall shrubs generally protrude ·above
winter snows, and hence can provide winter forage and cover as well as summer; and
5) this site tends to be narrow and linear and bordered by other ecosites, most commonly
shorter shrublands or, less often, forests. As a result, it can provide food to species
preferring neighboring sites for cover, or cover to species using neighboring sites for
food. (This intermixing of ecosites, which often enhances the wildlife value of all types
intermixed. is called "interspersion.") Tall shrub sites supporting relatively dense stands
of alder, however, are used by fewer kinds of wildlife than those dominated by willow
because they tend to have a poorly developed understory of shorter herbs and shrubs
(lower primary productivity) and because fewer wildlife species prefer alder forage.
Mammals commonly found in this site include species that are primarily riparian, such
as river otter, mink, beaver, and muskrat; species that use riparian areas seasonally, such
as moose, black and brown bear, and species that use tall or medium shrublands
regardless of proximity to water, e.g., snowshoe hare, red fox, lynx, ermine, and least
weasel. Similar categories of birds also use this site. Riparian species include blackpoll
warblers, gray-cheeked thrushes, orange-crowned and yellow warblers, northern shrikes,
and northern waterthrushes; shrubland species include willow ptarmigan and redpolls.
A variety of ground-nesting birds may also use this site, including pintail ducks, and
white-crowned and savannah sparrows. Because this site provides winter forage, it may
be critical to certain species as snows accumulate. Moose, in particular, are known to
depend heavily on tall shrub riparian areas during winter. The denser the willow shrubs
they support, the more effective this site will be in providing winter food and cover to
moose and other wildlife present during winter (See Table 1).

Recreational uses

This site is excellent for wildlife observation because of the diversity of vegetation and
accessibility to the site. Hunting (bear, muskox, moose, wolverine, and lynx), trapping,
and fishing are excellent; generally, this site is near char and grayling streams and in the
larger rivers, river chum salmon migrate. Boating, picnicing, gold panning, photography
and sightseeing, especially where abandoned gold dredges are found, are a few of the
potential recreational activities on this site.

Other products

Grazing

This site is a fair spring range, and a supreme summer and fall range. Associated
windswept gravel bars and beaches can provide some insect relief to grazing reindeer.

Willows (Salix spp.) can provide high quality forage during the summer months. Dense
shrub cover makes herding difficult during the summer months.

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 Biophysical Settings, 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.
Jorgensen, T., and D. Meidinger. 2015. The Alaska Yukon Region of the Circumboreal Vegetation Map (CBVM). CAFF Strategies Series Report. Conservation of Arctic Flora and Fauna, Akureyri, Iceland. ISBN: 978-9935-431-48-6.

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 6817150 – Alaska Arctic Floodplain. 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.

SCS (Soil Conservation Service). 1984. Ecological site descriptions, Seward Peninsula. U.S. Department of Agriculture, Soil Conservation Service, Alaska Field Office, Anchorage.

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. 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 Sonnen
Michael Singer

Approval

Blaine Spellman, 5/29/2025

Acknowledgments

The described soil – ecological site correlations in this document were reviewed by a workshop team 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: