Natural Resources
Conservation Service
Ecological site R226XY056AK
Herbaceous Hillsides (AK653 St Paul Island)
Accessed: 10/07/2026
-
Search
Major Land Resource Area or ecological site by name and/or ID.
PreviousSectionsNextGeneral 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.
Table 1. Dominant plant species
Tree Not specified
Shrub Not specified
Herbaceous Not specified
Physiographic features
This site occurs on sloping foot and side slopes of hills and volcanic cones where deep soils support highly productive stands of vegetation. This site occurs most frequently on north-facing slopes; however the site occurs on all aspects.
Table 2. Representative physiographic features
Landforms (1) Hillside
Elevation 60 – 120 ft Slope 30 – 100 % Climatic features
Table 3 Representative climatic features
Frost-free period (average) 120 days Freeze-free period (average) 100 days Precipitation total (average) 20 in BarLineFigure 1. Monthly precipitation range
BarLineFigure 2. Monthly average minimum and maximum temperature
">Influencing water features
Soil features
Soils are deep to very deep and well drained. Textures are medium and soil pH is slightly acid to neutral. Runoff is low and permeability is moderately rapid to rapid.
Table 4. Representative soil features
Surface texture (1) Medial sandy loam
Family particle size (1) Loamy
Drainage class Well drained Permeability class Moderately rapid to rapid Soil depth 40 – 60 in Surface fragment cover <=3" Not specified Surface fragment cover >3" Not specified Available water capacity
(0-40in)8.6 – 8.8 in Calcium carbonate equivalent
(0-40in)Not specified Electrical conductivity
(0-40in)Not specified Sodium adsorption ratio
(0-40in)Not specified Soil reaction (1:1 water)
(0-40in)6.1 – 7.3 Subsurface fragment volume <=3"
(Depth not specified)Not specified Subsurface fragment volume >3"
(Depth not specified)Not specified Ecological dynamics
State and transition model
More interactive model formats are also available. View Interactive Models
Click on state and transition labels to scroll to the respective textEcosystem states
State 1 submodel, plant communities
State 1
Elymus mollis/ Lupinus nootkatensisCommunity 1.1
Elymus mollis/ Lupinus nootkatensisForbs make up 90% and grasses 10% of the composition. Total annual vascular herbage production is 4250 pounds/acre.
Figure 3. Annual production by plant type (representative values) or group (midpoint values)
Additional community tables
Table 5. Community 1.1 plant community composition
Group Common name Symbol Scientific name Annual production () Foliar cover (%) Grass/Grasslike1 430–440 American dunegrass LEMOM2 Leymus mollis ssp. mollis 270–280 – wideleaf polargrass ARLA2 Arctagrostis latifolia 70–80 – shortstalk sedge CAPO Carex podocarpa 30–40 – foxtail ALOPE Alopecurus 10–20 – Forb1 3500–4000 Nootka lupine LUNO Lupinus nootkatensis 1900–1950 – seacoast angelica ANLU Angelica lucida 550–600 – Pacific hemlockparsley COGM Conioselinum gmelinii 340–345 – arctic sweet coltsfoot PEFR5 Petasites frigidus 255–265 – Tilesius' wormwood ARTI Artemisia tilesii 180–200 – boreal yarrow ACMIB Achillea millefolium var. borealis 135–145 – field horsetail EQAR Equisetum arvense 120–130 – captiate valerian VACA3 Valeriana capitata 70–80 – Bering chickweed CEBE2 Cerastium beeringianum 45–55 – larkspurleaf monkshood ACDE2 Aconitum delphiniifolium 45–50 – dandelion TARAX Taraxacum 30–40 – tall Jacob's-ladder POAC Polemonium acutiflorum 25–35 – springbeauty CLAYT Claytonia 0–5 – Interpretations
Animal community
Grasses and grass-likes such as wide leaf polargrass, shortstalk sedge, alpine timothy and bluegrass provide high value reindeer forage from spring to fall. These same grasses decline in forage value during the winter, at which time their forage value is moderate. The large variety of forbs provides excellent spring and summer forage. These areas are subject to snow accumulation during winter and on the north facing slopes; snow is retained for longer periods into the spring than surrounding sites.
Supporting information
Contributors
Swanson
Rangeland health reference sheet
Interpreting Indicators of Rangeland Health is a qualitative assessment protocol used to determine ecosystem condition based on benchmark characteristics described in the Reference Sheet. A suite of 17 (or more) indicators are typically considered in an assessment. The ecological site(s) representative of an assessment location must be known prior to applying the protocol and must be verified based on soils and climate. Current plant community cannot be used to identify the ecological site.
Author(s)/participant(s) Contact for lead author Date Approved by Approval date Composition (Indicators 10 and 12) based on Annual Production Indicators
-
Number and extent of rills:
-
Presence of water flow patterns:
-
Number and height of erosional pedestals or terracettes:
-
Bare ground from Ecological Site Description or other studies (rock, litter, lichen, moss, plant canopy are not bare ground):
-
Number of gullies and erosion associated with gullies:
-
Extent of wind scoured, blowouts and/or depositional areas:
-
Amount of litter movement (describe size and distance expected to travel):
-
Soil surface (top few mm) resistance to erosion (stability values are averages - most sites will show a range of values):
-
Soil surface structure and SOM content (include type of structure and A-horizon color and thickness):
-
Effect of community phase composition (relative proportion of different functional groups) and spatial distribution on infiltration and runoff:
-
Presence and thickness of compaction layer (usually none; describe soil profile features which may be mistaken for compaction on this site):
-
Functional/Structural Groups (list in order of descending dominance by above-ground annual-production or live foliar cover using symbols: >>, >, = to indicate much greater than, greater than, and equal to):
Dominant:
Sub-dominant:
Other:
Additional:
-
Amount of plant mortality and decadence (include which functional groups are expected to show mortality or decadence):
-
Average percent litter cover (%) and depth ( in):
-
Expected annual annual-production (this is TOTAL above-ground annual-production, not just forage annual-production):
-
Potential invasive (including noxious) species (native and non-native). List species which BOTH characterize degraded states and have the potential to become a dominant or co-dominant species on the ecological site if their future establishment and growth is not actively controlled by management interventions. Species that become dominant for only one to several years (e.g., short-term response to drought or wildfire) are not invasive plants. Note that unlike other indicators, we are describing what is NOT expected in the reference state for the ecological site:
-
Perennial plant reproductive capability:
Print Options
Sections
Font
AAAAOther
PrintThe Ecosystem Dynamics Interpretive Tool is an information system framework developed by the USDA-ARS Jornada Experimental Range, USDA Natural Resources Conservation Service, and New Mexico State University.
Accessibility statement
