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Ecological site VX226X00A109

Aleutian Shallow Cliffs and Slopes

Last updated: 6/14/2025
Accessed: 10/22/2025

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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): 226X–Aleutian Islands-Western Alaska Peninsula

MLRA 226X is the only MLRA in the Aleutian Alaska Region. It makes up about 5,190 square miles (13,450 square kilometers). The chain of islands includes west of Unimak Island to Attu Island, the Pribilof Islands, and the Sanak Islands. Characteristics and weather patterns of the far western end of the Alaska Peninsula is being included in this MLRA. It is bordered on the south by the Pacific Ocean and on the north by the Bering Sea (the Pribilof Islands are bordered on all sides by the Bering Sea). The coastline is complex, with many prominent headlands, sea cliffs, and narrow, steep-walled bays. Elevation ranges from sea level to more than 4,000 feet (1,220 meters) on many of the islands. Islands drain into the North Pacific and the Bering Sea by numerous short, steep-gradient rivers and streams. Lakes make up less than 2 percent of the area.

Geology
This MLRA includes more than 50 volcanoes, with an estimated 27 with activity since the 1950s. Volcanic rocks and unconsolidated deposits from the Quaternary and Tertiary period overlie a submarine ridge of Tertiary sedimentary rocks. Glacial ice once covered the eastern part of the area to approximately Umnak Island. West of Umnak, only the upper elevations were glaciated. Glaciers account for only 1.5 percent, occurring on the highest volcanoes. Volcanic activity has mantled most of the area with thick deposits of silty volcanic ash, sandy and gravelly cinders, and volcanic rubble. Lower elevations have areas of glacial influenced landforms. Recent coastal and fluvial deposits occur in scattered areas along the coast and on flood plains.

Water
Precipitation is adequate for crops generally. Permanent mountain streams feed most of the MLRA. The surface water generally is suitable for all uses. The ground water used in this MLRA is primarily from unconsolidated river valley sediments and bedrock aquifers. Iron is commonly high in the ground water, causing staining and precipitate in pipes. Wells are shallow with constant recharge by freshwater (rainfall and runoff); and are highly susceptible to contamination from runoff. The intrusion of seawater can be a problem along the coast.

Soils
The dominant soil orders in this MLRA are Andisols and Histosols. Miscellaneous areas (cinder land, rock outcrop, water, riverwash, and beaches) make up about 45 percent of this MLRA. The main soils are: Cryofibrists are poorly drained or very poorly drained and formed in thick deposits of organic material, along the margins of streams and lakeshores.
Tsammana series, Andic Dystrocryepts, Aquandic Dystrocryepts and Vitrandic Dystrocryepts are coarse marine sediments underlain by volcanic deposits. Zolotoi series and other Haplocryands are shallow to deep, well drained to excessively drained, and formed in moderately thick or thick deposits of silty to sandy volcanic ash and coarse sandy to gravelly cinders over basalt bedrock. Polovina series and other Vitricryands are shallow to deep, well drained to excessively drained, and formed in moderately thick or thick deposits of silty to sandy volcanic ash and coarse sandy to gravelly cinders over basalt bedrock.

Biological Resources
Higher elevation vegetation consists of a mosaic of dwarf shrub scrub and lower elevations are wet and dry grasslands. Peatland vegetation consists of low ericaceous shrub scrub. No naturally occurring forests occur on the islands. Aleutian shield fern, Steller sea lion, and the Aleutian Canada goose are currently listed as threatened or endangered. The area is an important winter habitat and nesting habitat for waterfowl and a variety of other birds. Some of the eastern islands support small herds of caribou.

Land Use
Commercial fishing is the primary enterprise, with fur seal harvesting for pelts and meat, Reindeer herding, and small cattle herds. Subsistence hunting, fishing, and gathering are critical for local residents. The major resource concerns are water erosion and mass wasting of soils. Overgrazing by reindeer has impacted vegetation and introduction of rats, dogs, cats, and foxes has severely impacted the nesting bird populations.

LRU notes

MLRA 226X, although very size-limited, contains a very complex and dynamic of weather patterns driven by the Pacific air currents on the southern exposure of the islands, and the Bering Sea to the north. The mixing or colliding of these two systems, creates very dramatic and intense storm systems that batter the islands. Weather variables from the Pacific to the Bering Sea, extent from west to east, as well as the extreme elevational gradient moving from sea level to Alpine life zone lends to a community diversity that is difficult to describe across an MLRA extent. Land Resource Units (LRUs) will need to be developed for this MLRA, as more extensive soils survey mapping is completed.

Classification relationships

Alaska-Aleutian province of the Pacific Mountain System.

USFS Description of Ecoregions of the United States
100 Polar Domain
120 Tundra Division
126 Bering Tundra (Southern) Province
M120 Tundra Division - Mountain Province
M127 Aleutian Oceanic Meadow--Heath Province
(USFS, 1994)

United States National Vegetation Classification
C04. Polar & High Montane Scrub, Grassland & Barrens Class
S12. Temperate to Polar Alpine & Tundra Vegetation Subclass
F031. Polar Tundra & Barrens Formation
D044. Arctic Tundra & Barrens Division
(USNVC, 2019)

LandFire BpS Model/Description Version: Nov. 2024
- 16520 Alaskan Pacific-Aleutian Alder-Salmonberry-Copperbush Shrubland
- 16510 Aleutian Mesic Herbaceous Meadow
(Landfire, 2009)

Ecological site concept

- Soils occur on cliff faces along the coastline, on escarpments, and other bedrock driven landforms.
- Soils are shallow to moderately deep to bedrock.
- No water table is associated with this site
- No ponding and no flooding, isolated areas of seeps may occur.
- Rock fragments are common in the profile and stone/boulder fields may be prevalent.
- Vegetation is sparse, however in areas where slope allows access, there is grazable tundra.
- Areas along the coastline may have an influence of ocean spray, introducing salt-tolerant species.
- This ecological site is the host to rare and endangered species.

Associated sites

VX226X00A107	Aleutian Steep Tundra Slopes Tephra dipslopes occur on the backslope of uplifts and along basalt influenced slopes with deep soils. The community is a more continuous cover of dwarf scrub and herbaceous species.
VX226X00A113	Aleutian Shrub Meadow Ashy Slopes Organic Ashy Slopes occur on the backslope of uplifts and along basalt influenced slopes with deep soils with an organic cap. The community is a robust Crowberry Mat with other ericaceous shrubs and sedges intermixed. Lichen and other bryophytes are common.

VX226X00A107

Aleutian Steep Tundra Slopes

Tephra dipslopes occur on the backslope of uplifts and along basalt influenced slopes with deep soils. The community is a more continuous cover of dwarf scrub and herbaceous species.

VX226X00A113

Aleutian Shrub Meadow Ashy Slopes

Organic Ashy Slopes occur on the backslope of uplifts and along basalt influenced slopes with deep soils with an organic cap. The community is a robust Crowberry Mat with other ericaceous shrubs and sedges intermixed. Lichen and other bryophytes are common.

Similar sites

VX226X00A102	Aleutian Dwarf Scrub Volcanics The volcanic cones and lava flows are shallow soils and have a similar Crowberry mat. The Shallow Cliffs and Slopes will have less of a mat cover with patches of grasses and interspersed shrubs and forbs.

VX226X00A102

Aleutian Dwarf Scrub Volcanics

The volcanic cones and lava flows are shallow soils and have a similar Crowberry mat. The Shallow Cliffs and Slopes will have less of a mat cover with patches of grasses and interspersed shrubs and forbs.

Table 1. Dominant plant species

Tree	Not specified
Shrub	(1) Vaccinium ovalifolium (2) Rubus spectabilis
Herbaceous	(1) Athyrium filix-femina (2) Calamagrostis canadensis

Legacy ID

R226XY109AK

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Physiographic features

- Landforms are dominantly sea cliff faces, and escarpment scarp faces or slopes.
- Slope is generally steep, ranging from 30 to 60 percent, but on ridge and cliff shoulders and summits will have slightly less slope (10 to 60 percent).
- Due to high slopes, runoff is generally high to very high.
- Elevation ranges from nearly sea level (20 ft) to commonly 3850 feet. However, some communities may occur on bedrock outcrops on the upper mountain slopes (7040 feet).
- Ecological site occurs on all aspects.

Table 2. Representative physiographic features

Hillslope profile	(1) Backslope (2) Shoulder (3) Summit
Landforms	(1) Island > Mountain (2) Sea cliff (3) Scarp slope (4) Beach ridge (5) Beach terrace > Rise (6) Terrace > Rise
Runoff class	High to very high
Flooding frequency	None
Ponding frequency	None
Elevation	20 – 3,850 ft
Slope	10 – 60%
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 frequency	Not specified
Elevation	10 – 7,040 ft
Slope	90%

Climatic features

The climate is similar to that on the arctic coastal plain, except Islands are impacted by the tides, air movement, and storms influenced by the Pacific Ocean and Bering Sea, and really no inland influence. Winters are less severe than those on the coastal plain, with temperature ranges of 18 to 27 degrees F (10 to 15C), as compared to a 54 degrees F (30C) range on the coastal plain. The climate is characterized by fog and rain, with the amount of precipitation varying little from month to month. Annual precipitation varies from 21 in (530 mm) to more than 78 in (2,000 mm) across all islands. The higher elevations average 46 to 58 inches per year, with smaller islands receiving less precipitation than larger islands. Winds are often severe on the islands. Pacific Ocean water moving northward through the straits between the islands produces complex mixing with Bering Sea water, including upwelling. The Pribilof Islands in the Bering Sea are the southern limit of the arctic ice pack in winter (USDA-NRCS 2022). Weather information below is captured by climate stations located at Dutch Harbor and Cold Bay. The location of these stations represents only a small segment of the dynamic climate across this chain of islands.

Table 4. Representative climatic features

Frost-free period (characteristic range)	78-92 days
Freeze-free period (characteristic range)	122-136 days
Precipitation total (characteristic range)	46-58 in
Frost-free period (actual range)	75-95 days
Freeze-free period (actual range)	119-139 days
Precipitation total (actual range)	43-61 in
Frost-free period (average)	85 days
Freeze-free period (average)	129 days
Precipitation total (average)	52 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

Climate stations used

(1) DUTCH HARBOR [USC00502587], Unalaska, AK
(2) COLD BAY AP [USW00025624], Cold Bay, AK

Influencing water features

No water table is associated with the cliffs and escarpment landforms. Runoff from this site does feed into the aquifers and streams influencing lower elevation landforms.

Wetland description

Seeps and depressions, or pockets within the cliff faces and ridge tops, may pond water for short periods, providing added benefit to vegetation. But these are small, isolated communities in the overall landscape and are not classified in the current literature as wetlands.

Soil features

- Parent material is predominantly intermixed sedimentary and igneous residuum
- Surface texture is commonly silty loam and is very stony and medial
- Soils are shallow, with lithic bedrock at 10 to 20 inches below the mineral surface. In some areas where birds will perch, an organic layer may be present.
- Soils are well drained with moderate permeability. Slope affects permeability at this site.
Correlated components include:
- Maritime dwarf scrub - gravelly colluvial slopes
- Lithic Cryorthents
- Lithic Haplocryands

Table 5. Representative soil features

Parent material	(1) Residuum – igneous and sedimentary rock (2) Colluvium – igneous rock
Surface texture	(1) Medial, cobbly, very stony silt loam (2) Loamy sand
Drainage class	Well drained
Permeability class	Moderate
Depth to restrictive layer	10 – 20 in
Soil depth	10 – 20 in
Surface fragment cover <=3"	Not specified
Surface fragment cover >3"	Not specified
Available water capacity (0-40in)	3 – 4.9 in
Soil reaction (1:1 water) (0-10in)	5.6 – 6.5
Subsurface fragment volume <=3" (0-60in)	5 – 10%
Subsurface fragment volume >3" (0-60in)	15 – 40%

Table 6. Representative soil features (actual values)

Drainage class	Somewhat poorly drained to somewhat excessively drained
Permeability class	Moderately slow to moderately rapid
Depth to restrictive layer	10 – 24 in
Soil depth	10 – 24 in
Surface fragment cover <=3"	15%
Surface fragment cover >3"	5%
Available water capacity (0-40in)	0.6 – 7.5 in
Soil reaction (1:1 water) (0-10in)	4.5 – 6.5
Subsurface fragment volume <=3" (0-60in)	11%
Subsurface fragment volume >3" (0-60in)	70%

Ecological dynamics

The climate of the Aleutian Islands is a harsh climate to survive. The islands experience strong winds and persistent fog. Heavy precipitation events with fairly uniform temperatures throughout the year limit the type of vegetation that will grow. Specifically, preventing trees from establishing Trees are absent from the Aleutian Province in response to the cool average temperatures.

Tall shrubs, to a limited extent, and low shrubs and scrub are prevalent on the islands. Some of these are the Aleutian alder, salmonberry, black crowberry, along with other dwarf shrubs. These particular species occur along the cliff faces and ridge tops. Wind exposure, and in areas within the reaches of salt-water spray, have sparse vegetation, but also hold unique niches for species such as the Aleutian alder, salmonberry, and a variety of ferns, mosses, and lichens to reside.

Only a limited amount of vegetative analysis has been completed across the island chain. Research is predominantly limited to Amchitka, Buldir, and a few other accessible islands. Considering the broad reach of the Aleutian Island chain and the variable is oceanic influence, volcanic activity and historical impacts, there is concern that many species as well as community types are missing. As more information is gained, these concepts will be improved.

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. Alder-Barclay's Willow/Salmonberry-Oval-leaf Blueberry

1.2. Tundra Alkaligrass/Eurhynchium Moss/Granulose Orange Lichen

1.3. Common Ladyfern/Bluejoint

State 1
Reference State

The Aleutian Shallow Cliffs and Slopes ecological site is influenced by two outside forces that create unique vegetation patterns within the Reference State. The first community is the general or common community for this ecological site. The second community is a result of proximity to the ocean and tidal influence creating salt spray, especially during intense storm surges. The third community is a result of prime perch habitat for birds, both shore birds and land birds. These bird perches create a nutrient rich soil that encourages small, isolated areas with a more robust vegetative community.

Dominant plant species

alder (Alnus), shrub
willow (Salix), shrub
red elderberry (Sambucus racemosa), shrub
salmonberry (Rubus spectabilis), shrub
oval-leaf blueberry (Vaccinium ovalifolium), shrub
tundra alkaligrass (Puccinellia tenella), grass
wildrye (Elymus), grass
bluejoint (Calamagrostis canadensis), grass
sedge (Carex), grass
spike bentgrass (Agrostis exarata), grass
common ladyfern (Athyrium filix-femina), other herbaceous
green false hellebore (Veratrum viride), other herbaceous
common cowparsnip (Heracleum maximum), other herbaceous
saxifrage (Saxifraga), other herbaceous
fireweed (Chamerion angustifolium), other herbaceous
spikemoss (Selaginella), other herbaceous
granulose orange lichen (Caloplaca granulosa), other herbaceous

Community 1.1
Alder-Barclay's Willow/Salmonberry-Oval-leaf Blueberry

Plant Community 1.1 is a patchwork of two distictive communities of a tall shrub community dominanted by alders, and then the ericaceous/dwarf-scrub community. The major indicator species are Sitka alder (Alnus viridis ssp. sinuata), mountain alder (Alnus viridis ssp. crispa), barclay's willow (Salix barclayi), red elderberry (Sambucus racemosa) for the tall shrub community; and salmonberry (Rubus spectabilis), oval-leaf blueberry (Vaccinium ovalifolium), and black crowberry (Empetrum nigrum). Other common species within these two communities are devils club (Oplopanax horridus), bluejoint (Calamagrostis canadensis), common ladyfern (Athyrium filix-femina), spreading woodfern (Dryopteris expansa), boreal yarrow (Achillea millefolium var. borealis), fireweed (Chamerion angustifolium ssp. angustifolium), Lapland cornel (Cornus suecica), calthaleaf avens (Geum calthifolium), and Canadian burnet (Sanguisorba canadensis). As slopes lessen, or at the lower break of steep cliff faces wildrye (Elymus spp.), licorice-root (Ligusticum spp.), and anenomes (Anenome spp.) are a common community group. Along slopes where seepage is common, ferns are very prolific. Common ladyfern and brittle bladderfern (Cystopteris fragilis) are the key indicators. They are common with American alpine speedwell (Veronica stelleri), clubmoss mountain heather (Cassiope lycopodioides), northern asphodel (Tofieldia coccinea), least willow (Salix rotundifolia), heartleaf springbeauty (Claytonia sibirica), bract saxifrage (Saxifraga bracteata), weak saxifrage (Saxifraga rivularis), and club spikemoss (Selaginella selaginoides).

Dominant plant species

mountain alder (Alnus viridis ssp. crispa), shrub
Sitka alder (Alnus viridis ssp. sinuata), shrub
Barclay's willow (Salix barclayi), shrub
red elderberry (Sambucus racemosa), shrub
salmonberry (Rubus spectabilis), shrub
oval-leaf blueberry (Vaccinium ovalifolium), shrub
black crowberry (Empetrum nigrum), shrub
devilsclub (Oplopanax horridus), shrub
bluejoint (Calamagrostis canadensis), grass
wildrye (Elymus), grass
common ladyfern (Athyrium filix-femina), other herbaceous
spreading woodfern (Dryopteris expansa), other herbaceous
boreal yarrow (Achillea millefolium var. borealis), other herbaceous
fireweed (Chamerion angustifolium), other herbaceous
Lapland cornel (Cornus suecica), other herbaceous
calthaleaf avens (Geum calthifolium), other herbaceous
Canadian burnet (Sanguisorba canadensis), other herbaceous
brittle bladderfern (Cystopteris fragilis), other herbaceous
licorice-root (Ligusticum), other herbaceous
anemone (Anemone), other herbaceous

Community 1.2
Tundra Alkaligrass/Eurhynchium Moss/Granulose Orange Lichen

Salt-spray associated cliff vegetation is a unique community found on cliff faces to the cliff summits along the coastline, as well as beach boulders and rock pinnacles. Tundra alkaligrass (Puccinellia langeana), eurhynchium moss (Eurhynchium praelongum), and granulose orange lichen (Caloplaca granulosa) are the prominant cover along these cliff faces within the salt spray affect. Tundra alkaligrass is very healthy and productive, especially where bird populations are high. Other common species in these areas are villous cinquefoil (Potentilla villosa), North Pacific draba (Draba hyperborea), and bract saxifrage (Saxifraga bracteata).

Dominant plant species

tundra alkaligrass (Puccinellia tenella ssp. alaskana), grass
eurhynchium moss (Eurhynchium praelongum), other herbaceous
granulose orange lichen (Caloplaca granulosa), other herbaceous
villous cinquefoil (Potentilla villosa), other herbaceous
North Pacific draba (Draba hyperborea), other herbaceous
bract saxifrage (Saxifraga sibirica), other herbaceous

Community 1.3
Common Ladyfern/Bluejoint

Common ladyfern (Athyrium filix-femina), green false hellebore (Veratrum viride), common cowparsnip (Heracleum maximum), claspleaf twistedstalk (Streptopus amplexifolius), seacoast (Angelica lucida), bluejoint (Calamagrostis canadensis), Tundra alkaligrass (Puccinella lungeana) is very healthy and productive, and fireweed (Chamerion angustifolium ssp. angustifolium). Wildrye (Elymus spp.), coiled sedge (Carex circinata), northern bentgrass (Agrostis mertensii), and navel lichen (Umbilicaria proboscidea). Slope seep is common in many of these areas, common ladyfern and brittle bladderfern (Cystopteris fragilis) are very prolific. Additional common species include spreading woodfern (Dryopteris expansa), American alpine speedwell (Veronica stelleri), clubmoss mountain heather (Cassiope lycopodioides), northern asphodel (Tofieldia coccinea), least willow (Salix rotundifolia), heartleaf springbeauty (Claytonia sibirica), bract saxifrage (Saxifraga bracteata), weak saxifrage (Saxifraga rivularis), and club spikemoss (Selaginella selaginoides). Other common herbaceous species include Nootka lupine (Lupinus nootkatensis), Canada goldenrod (Solidago canadensis var. lepida), tall Jacob's-ladder (Polemonium acutiflorum), Alaska Indian paintbrush (Castilleja unalaschcensis), Canadian burnet (Sanguisorba canadensis), captiate valerian (Valeriana capitata), flat-top pussytoes (Antennaria dioica), umbel bittercress (Cardamine oligosperma var. katschatica), boreal yarrow (Achillea millefolium var. borealis), Alaska arnica (Arnica unalaschcensis), arctic daisy (Chrysanthemum arcticum L. ssp. arcticum), calthaleaf avens (Geum calthifolium), western buttercup (Ranunculus occidentalis), longawn sedge (Carex macrochaeta), red fescue (Festuca rubra), spike bentgrass (Agrostis exarata), rough bentgrass (Agrostis scabra), Bering's tufted hairgrass (Deschampsia beringensis), and black crowberry (Empetrum nigrum).

Dominant plant species

clubmoss mountain heather (Cassiope lycopodioides), shrub
least willow (Salix rotundifolia), shrub
tundra alkaligrass (Puccinellia tenella ssp. alaskana), grass
bluejoint (Calamagrostis canadensis), grass
wildrye (Elymus), grass
coiled sedge (Carex circinata), grass
northern bentgrass (Agrostis mertensii), grass
common ladyfern (Athyrium filix-femina), other herbaceous
green false hellebore (Veratrum viride), other herbaceous
common cowparsnip (Heracleum maximum), other herbaceous
claspleaf twistedstalk (Streptopus amplexifolius), other herbaceous
seacoast angelica (Angelica lucida), other herbaceous
fireweed (Chamerion angustifolium ssp. angustifolium), other herbaceous
navel lichen (Umbilicaria proboscidea), other herbaceous

Additional community tables

Interpretations

Animal community

The area provides nesting habitat for a variety of birds, including cliff dwelling species and rock sandpiper, whiskered auklet, rock ptarmigan, song sparrow, rosy finch, and winter wren. Some of the eastern islands support small herds of caribou that may utilize ridgelines, and accessible slopes.

Recreational uses

Tourism and wildland recreation are becoming increasingly important. Subsistence hunting and gathering provide food and a variety of other resources to local residents and are a major component of the local economy.

Wood products

None

Other information

The major soil resource concerns are erosion and mass wasting of soils, particularly on steep cliff faces and slopes. Minimizing trailing and destabilizing of the cliff faces is critical.

Supporting information

Inventory data references

Very limited data is available and resides more on the coastal zone than the higher volcanics. Information used to build this ecological site was obtained from existing land cover and vegetation maps, literature review, and vegetative summaries from partnering agencies.

References

Hansford T. Shacklette, L. W. Durrell, James A. Erdman, John R. Keith, William M. Klein, Hildur Krog, Herman Persson, H. Skuja, and William A. Weber. 1969. Vegetation of Amchitka Island, Aleutian Islands, Alaska. Geological Survey Professional Paper 648. United States Geological Survey, United States Government Printing Office, Washington : 1969.

Other references

Landfire National Vegetation Dynamics Models; USGS; http://www.LANDFIRE.gov/index.php, 2009 (Date accessed)

USDA PLANTS Database; http://plants.usda.gov, 2021

USNVC [United States National Vegetation Classification]. 2019. United States National Vegetation Classification Database, V2.03. Federal Geographic Data Committee, Vegetation Subcommittee, Washington DC. USNVC: http://usnvc.org/

AMUNDSEN, C.C. 1972. Amchitka Bioenvironmental Program: Plant ecology of Amchitka Island, Final Report. Batelle, Columbus Laboratories, under AEC Prime, Contract No. AT(26-l)-171. 27 p.

AMUNDSEN, c.c. and E.E.C. CLEBSCH. 1971. Dynamics of the terrestrial ecosystem vegetation of Amchitka Island, Alaska. Bioscience 21:619-623.

AMUNDSEN, C.C. 1977. Terrestrial plant ecology. Pages 203-226 in M.L. Merritt and R.G. Fuller, eds. The environment of Amchitka Island, Alaska. ERDA TID-26712.

Bailey, R.G. [in prep.] Description of the ecoregions of the United States. 2d ed. Misc. Publ. No. 1391 [rev.]. Washington, DC: U.S. Department of Agriculture, Forest Service. Bailey, Robert G.; Avers, Peter E.; King, Thomas; McNab, W. Henry, eds. 1994. Ecoregions and subregions of the United States (map). Washington, DC: U.S. Geological Survey. Scale 1: 7,500,000; colored. Accompanied by a supplementary table of map unit descriptions compiled and edited by McNab, W. Henry, and Bailey, Robert G. Prepared for the U.S. Department of Agriculture, Forest Service.

BANK, T.B. II. 1951. Botanical and ethnobotanical studies in the Aleutian Islands. I. Aleutian vegetation and Aleut culture. Mich. Acad. Sci., Arts, and Lett. 37:13-30 + 6 plates.

BYRD, G.V. 1984. Vascular vegetation of Buldir Island, Aleutian Islands, Alaska compared to another Aleutian Island. Arctic 37(1):37-48.

Fosberg, Francis Raymond. "Succession and condition of ecosystems." (1967).

Hultén, Eric (1937) Flora of the Aleutian Islands and westernmost Alaska Peninsula with notes on the flora of Commander islands. Stockholm, Thule. 397 pp. 2nd ed. 1960 (series: Flora et vegetation mundi, vol. 1) Weinheim, Cramer. 376 pp.

SHACKLETTE, H.T., L.W. ERDMAN-J.R. KEITH, W.M. KLEIN, H. KROG, H. PERSSON, H. SKUJA, and W.A. WEBER. 1969. Vegetation of Amchitka Island, Aleutian Islands, Alaska. U.S. Geol. Surv. Prof. Pap. 648. 66p.

Swanson, D.J., Lehner, D., Zimmerman, J., and Pauling, D. Range survey of Nunivak Island, Alaska, 1986.

TATEWAKI. M. 1963. Phytogeography of. the islands of the north Pacific Ocean. Pages 23-27 in J.L. Gressitt, ed. Pacific Basin Biogeography. lOth Pacific Science Congress. Bishop Museum Press, Honolulu.

TALBOT, S.S., S.L. TALBOT, and L.R. Walker. 2010. Post-eruption legacy effects and their implications for long-term recovery of the vegetation on Kasatochi Island, Alaska. Arctic, Antarctic, and Alpine Research, Vol. 42, No. 3, pp. 285-296

WALKER., H. 1945. Plants of the Aleutian Islands. Pages 63-;71 in Collins, H.B., Jr., A.H. Clark, and E.H. Walker, eds. The Aleutian Islands: Their people and natural history. Smithsonian Inst. War Background Studies 21, Publ. 3775.

Contributors

Marji Patz
Tyler Annetts

Approval

Blaine Spellman, 6/14/2025

Acknowledgments

Blaine Spellman, Ecological Site Data Quality Specialist and Phil Barber, Ecological Site Specialist within Alaska, for your review and guidance of the PES development. Matt Mayer for assisting with R Scripts on weather, as well as Nathan Roe for assistance with R scripts on site data summaries.

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	06/14/2025
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:

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Natural ResourcesConservation Service

Ecological site VX226X00A109

Aleutian Shallow Cliffs and Slopes

Last updated: 6/14/2025 Accessed: 10/22/2025

General information

MLRA notes

LRU notes

Classification relationships

Ecological site concept

Associated sites

Similar sites

Table 1. Dominant plant species

Legacy ID

Ecosystem states

State 1 submodel, plant communities

Natural Resources
Conservation Service

Last updated: 6/14/2025
Accessed: 10/22/2025