Ecological site F044AP902MT

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): 044A–Northern Rocky Mountain Valleys

Major Land Resource Area (MLRA): 044A–Northern Rocky Mountain Valleys
This MLRA includes the northern portion of the Northern Rocky Mountain Valleys Province of the Rocky Mountain System. The mountain valleys are deeply dissected and are typically bordered by mountains trending north to south. The nearly level broad flood plains are bordered by gently to strongly sloping terraces and alluvial fans. The surrounding mountains and in some areas the valleys experienced glaciation. The average precipitation is 12 to 16 inches generally, though can vary widely. The dominant soil orders are Inceptisols, Mollisols and Andisols. The valleys support coniferous forests, shrublands and grasslands.
Description of MLRAs can be found in: United States Department of Agriculture, Natural Resources Conservation Service. 2006. 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.

Available electronically at: http://www.nrcs.usda.gov/wps/portal/nrcs/detail/soils/ref/?cid=nrcs142p2_053624#handbook

Classification relationships

ASSOCIATED HABITAT TYPES:
PSME/PSSP6
PSME/CARU-ARUV
PIPO/PSSP6

Ecological site concept

• Site does not receive any additional water
• Dominant Cover: Coniferous Forest
This is an open canopy woodland of ponderosa pine or Douglas fir with an understory of either native bunchgrasses, namely bluebunch wheatgrass, or an understory of the rhizomatous pinegrass with associated kinnikinnick, a low growing shrub. The understory production ranges from 300 to 800 dry pounds per acre.
• Soils are
o Generally not limy (limited extent)
o Shallow (less than 50cm deep to bedrock; lithic, or paralithic root restrictive layer)
o Not ashy or medial textural family
o Typically less than 5% stone and boulder surface cover (<15% max)
• Soil surface texture ranges from gravelly silt loam to stony loam in surface mineral 4”
• Parent material is slope alluvium or colluvium over residuum weathered from granite
• Drainage class is well drained; no flooding frequency
• Site Landform: escarpments, hillslopes, mountains
• Moisture Regime: ustic
• Temperature Regime: frigid
• Elevation Range: 2200-5500 ft
• Slope: 4-35%

Associated sites

F044AP903MT	Upland Cool Woodland Group This associated ecological site resides in slightly moister site conditions than this ecological site.
F044AP905MT	Upland Warm Woodland Group This associated ecological site resides in warmer, drier site conditions than this ecological site.

F044AP903MT

Upland Cool Woodland Group

This associated ecological site resides in slightly moister site conditions than this ecological site.

F044AP905MT

Upland Warm Woodland Group

This associated ecological site resides in warmer, drier site conditions than this ecological site.

Similar sites

F044AH003MT	Montane Moderately Warm Dry Coniferous Seeley, Swan, Flathead and Tobacco Valleys This similar ecological site has dry site conditions and an overstory of Douglas fir, but is limited to the north central portion of this MLRA.

F044AH003MT

Montane Moderately Warm Dry Coniferous Seeley, Swan, Flathead and Tobacco Valleys

This similar ecological site has dry site conditions and an overstory of Douglas fir, but is limited to the north central portion of this MLRA.

Table 1. Dominant plant species

Tree	(1) Pseudotsuga menziesii var. glauca (2) Pinus ponderosa
Shrub	Not specified
Herbaceous	(1) Pseudoroegneria spicata (2) Calamagrostis rubescens

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Physiographic features

Table 2. Representative physiographic features

Landforms	(1) Valley > Hillslope (2) Valley > Escarpment
Elevation	671 – 1,676 m
Slope	4 – 35%
Water table depth	152 cm
Aspect	W, NW, N, NE, E, SE, S, SW

Climatic features

• Moisture Regime: ustic
• Temperature Regime: frigid
• Representative Value (RV) of range of Mean Annual Precipitation: 16-32 inches
• Representative Value (RV) of range of Mean Average Annual Temperature: 39-46 degrees
• Representative Value (RV) of range of Frost Free Days: 70-90 days

Table 3. Representative climatic features

Frost-free period (characteristic range)	49-103 days
Freeze-free period (characteristic range)	97-137 days
Precipitation total (characteristic range)	305-533 mm
Frost-free period (actual range)	15-117 days
Freeze-free period (actual range)	77-145 days
Precipitation total (actual range)	279-584 mm
Frost-free period (average)	76 days
Freeze-free period (average)	115 days
Precipitation total (average)	406 mm

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) WHITEFISH [USC00248902], Whitefish, MT
(2) BONNERS FERRY [USC00101079], Bonners Ferry, ID
(3) BAYVIEW MODEL BASIN [USC00100667], Athol, ID
(4) POLSON KERR DAM [USC00246640], Polson, MT
(5) OVANDO 9 SSE [USC00246304], Helmville, MT
(6) STEVENSVILLE [USC00247894], Stevensville, MT
(7) TRIDENT [USC00248363], Three Forks, MT
(8) TOWNSEND [USC00248324], Townsend, MT
(9) DRUMMOND AVIATION [USW00024139], Drummond, MT

Soil features

• Soils are
o Generally not limy (limited extent)
o Shallow (less than 50 cm deep to bedrock; lithic, or paralithic root restrictive layer)
o Not ashy or medial textural family
o Typically less than 5 percent stone and boulder surface cover (less than 15 percent max)
• Soil surface texture ranges from gravelly silt loam to stony loam in surface mineral 4”
• Parent material is slope alluvium or colluvium over residuum weathered from granite
• Drainage class is well drained; no flooding frequency

Table 4. Representative soil features

Parent material	(1) Slope alluvium – granite (2) Colluvium – granite (3) Residuum – granite
Surface texture	(1) Gravelly silt loam (2) Stony loam
Drainage class	Well drained
Soil depth	25 – 48 cm
Surface fragment cover >3"	0 – 15%

Interpretations

Animal community

Forage production of palatable grass species is low, though pinegrass can dominate areas. Use by horses and cattle on gentler slopes. In areas with undergrowth dominated by bunchgrasses, bluebunch wheatgrass and rough fescue, the livestock grazing potential is moderate due to the palatability of these species.

Moderate use by deer and elk in winter throughout this site.

Hydrological functions

This is a dry forest site in which the native bunchgrass understory serves to hold water longer and deeper in the soil. If there are disruptions via drought or management in which native bunchgrasses are replaced by annual or non-native grass species, there will be less water stored in the soil and available for plant use.

Recreational uses

HIKING, BIKING, PHOTOGRAPHY

Wood products

In the pinegrass dominated undergrowth areas of this site, timber production is low to moderate and site preparation and timber management must include scarification of thick sod-forming pinegrass in order to allow tree regeneration.

In areas that are low elevation, on sunny exposures with open growth, low tree canopy cover and undergrowth dominated by bunchgrasses, timber production is very low to low, and tree regeneration can be impeded by thick cover of bunchgrass

Supporting information

Other references

Pfister, Robert D., et al. "Forest habitat types of Montana." Gen. Tech. Rep. INT-GTR-34. Ogden, UT: US Department of Agriculture, Forest Service, Intermountain Forest & Range Experiment Station. 174 p. 34 (1977).

Contributors

Jay Skovlin
Stephanie Shoemaker

Approval

Kirt Walstad, 9/08/2023

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	12/25/2024
Approved by	Kirt Walstad
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 F044AP902MT

Shallow Warm Woodland Group

Last updated: 9/08/2023 Accessed: 12/25/2024

General information

MLRA notes

Classification relationships

Ecological site concept

Associated sites

Similar sites

Table 1. Dominant plant species

Natural Resources
Conservation Service

Last updated: 9/08/2023
Accessed: 12/25/2024