East Cascades Moist Mountain Conifer Forest

EVT 7018East Cascades Mesic Montane Mixed-Conifer Forest and Woodland
CES204.086GNRTreeConifer
Summary
This ecological system occurs on the upper east slopes of the Cascades in Washington, south of Lake Chelan and south to Mount Hood in Oregon. Elevations range from 610 to 1220 m (2000-4000 feet) in a very restricted range occupying less than 5% of the forested landscape in the east Cascades. This system is associated with a submesic climate regime with annual precipitation ranging from 100 to 200 cm (40-80 inches) and maximum winter snowpacks that typically melt off in spring at lower elevations. This ecological system is composed of variable montane coniferous forests typically below Pacific silver fir forests along the crest east of the Cascades. This system also includes montane forests along rivers and slopes, and in mesic "coves" which were historically protected from wildfires. Most occurrences of this system are dominated by a mix of Pseudotsuga menziesii with Abies grandis and/or Tsuga heterophylla. Several other conifers can dominate or codominate, including Thuja plicata, Pinus contorta, Pinus monticola, and Larix occidentalis. Abies grandis and other fire-sensitive, shade-tolerant species dominate forests on many sites once dominated by Pseudotsuga menziesii and Pinus ponderosa, which were formerly maintained by wildfire. They are very productive forests in the eastern Cascades which have been priority stands for timber production. Mahonia nervosa, Linnaea borealis, Paxistima myrsinites, Acer circinatum, Spiraea betulifolia, Symphoricarpos hesperius, Cornus nuttallii, Rubus parviflorus, and Vaccinium membranaceum are common shrub species. The composition of the herbaceous layer reflects local climate and degree of canopy closure and contains species more restricted to the Cascades, for example, Achlys triphylla, Anemone deltoidea, and Vancouveria hexandra. Typically, stand-replacement fire-return intervals are 150-500 years with moderate-severity fire-return intervals of 50-100 years.
Source: NatureServe Explorer
Vegetation
Most occurrences of this system are dominated by a mix of Pseudotsuga menziesii with Abies grandis and/or Tsuga heterophylla. Several other conifers can dominate or codominate, including Thuja plicata, Pinus contorta, Pinus monticola, and Larix occidentalis. Abies grandis and other fire-sensitive, shade-tolerant species dominate forests on many sites once dominated by Pseudotsuga menziesii and Pinus ponderosa, which were formerly maintained by wildfire. They are very productive forests in the eastern Cascades which have been priority stands for timber production. Mahonia nervosa, Linnaea borealis, Paxistima myrsinites, Acer circinatum, Spiraea betulifolia, Symphoricarpos hesperius, Cornus nuttallii, Rubus parviflorus, and Vaccinium membranaceum are common shrub species. The composition of the herbaceous layer reflects local climate and degree of canopy closure and contains species more restricted to the Cascades, for example, Achlys triphylla, Anemone deltoidea, and Vancouveria hexandra.
Source: NatureServe Explorer
Environment
This ecological system occurs on the upper east slopes of the Cascades in Washington, south of Lake Chelan and south to Mount Hood in Oregon. Elevations range from 610 to 1220 m (2000-4000 feet) in a very restricted range occupying less than 5% of the forested landscape in the east Cascades. This system is associated with a submesic climate regime with annual precipitation ranging from 100 to 200 cm (40-80 inches) and maximum winter snowpacks that typically melt off in spring at lower elevations. This ecological system is composed of variable montane coniferous forests typically below Pacific silver fir forests along the crest east of the Cascades. This system also includes montane forests along rivers and slopes, and in mesic "coves" which were historically protected from wildfires.
Source: NatureServe Explorer
Dynamics
Typically, stand-replacement fire-return intervals are 150-500 years with moderate-severity fire-return intervals of 50-100 years. Landfire VDDT models: R#MCONm Eastside mixed conifer moist (GF/DF) model is applied with stages A-B-E.
Source: NatureServe Explorer
Distribution
This ecological system occurs on the upper east slopes of the Cascades in Washington, south of Lake Chelan and south to Mount Hood in Oregon.
Source: NatureServe Explorer
Ecologically Associated Plant Species

Plant species that characterize this ecosystem type, organized by vegetation stratum. These are species ecologically associated with the ecosystem, not confirmed present in any specific area.

Tree canopy

Abies grandis, Larix occidentalis, Pinus contorta, Pinus monticola, Pinus ponderosa, Pseudotsuga menziesii, Thuja plicata, Tsuga heterophylla

Shrub/sapling (tall & short)

Acer circinatum, Berberis nervosa, Cornus nuttallii, Paxistima myrsinites, Rubus parviflorus, Spiraea betulifolia, Symphoricarpos hesperius, Vaccinium membranaceum

Short shrub/sapling

Linnaea borealis

Herb (field)

Achlys triphylla, Anemone deltoidea, Botrychium paradoxum, Botrychium pedunculosum, Lomatium cuspidatum, Pedicularis rainierensis, Penstemon barrettiae, Sidalcea oregana var. calva, Sisyrinchium sarmentosum, Vancouveria hexandra

Nonvascular

Cortinarius wiebeae, Hygrophorus caeruleus, Lyophyllum gracile
Source: NatureServe Ecological System assessment
Ecologically Associated Animals (11)

Animal species ecologically associated with this ecosystem type based on NatureServe assessment. These are species whose habitat requirements overlap with this ecosystem, not confirmed present in any specific roadless area.

Mammals (5)

Common NameScientific NameG-Rank
Southern Red-backed VoleClethrionomys gapperiG5
North American PorcupineErethizon dorsatumG5
Long-tailed VoleMicrotus longicaudusG5
Montane VoleMicrotus montanusG5
Long-tailed WeaselNeogale frenataG5

Amphibians (2)

Common NameScientific NameG-Rank
Oregon Slender SalamanderBatrachoseps wrightiG3
Oregon Spotted FrogRana pretiosaG2

Fish (1)

Common NameScientific NameG-Rank
Oregon ChubOregonichthys crameriG3

Molluscs (2)

Common NameScientific NameG-Rank
Rocky Mountain DuskysnailColligyrus greggiG4
Columbia OregonianCryptomastix hendersoniG3Q

Other (1)

Common NameScientific NameG-Rank
One-band JugaJuga sp. 8G2G3
Source: NatureServe Ecological System assessment
At-Risk Species Associated with this Ecosystem (15)

Species with conservation concern that are ecologically associated with this ecosystem type. G-Rank indicates global conservation status: G1 (critically imperiled) through G5 (secure). ESA status indicates U.S. Endangered Species Act listing.

Common NameScientific NameG-RankESA Status
Oregon Slender SalamanderBatrachoseps wrightiG3--
Peculiar MoonwortBotrychium paradoxumG3G4--
Stalked MoonwortBotrychium pedunculosumG3G4--
a fungusCortinarius wiebeaeG2--
Columbia OregonianCryptomastix hendersoniG3Q--
a fungusHygrophorus caeruleusG3--
One-band JugaJuga sp. 8G2G3--
Wenatchee Desert-parsleyLomatium cuspidatumG2--
a fungusLyophyllum gracileG2G3--
Oregon ChubOregonichthys crameriG3Delisted
Mount Rainier LousewortPedicularis rainierensisG2--
Barrett's BeardtonguePenstemon barrettiaeG2--
Oregon Spotted FrogRana pretiosaG2Threatened
Wanatchee Mountains Checker-mallowSidalcea oregana var. calvaG5T1Endangered
Pale Blue-eyed-grassSisyrinchium sarmentosumG2--
Source: NatureServe Ecological System assessment
Component Associations (14)

Plant community associations that occur within this ecological system. Associations are the finest level of the U.S. National Vegetation Classification (USNVC) and describe specific, repeating assemblages of plant species. Each association represents a distinct community type that may be found where this ecosystem occurs.

NameG-Rank
Abies grandis / Acer circinatum ForestG4 NatureServe
Abies grandis / Achlys triphylla ForestG3 NatureServe
Abies grandis / Arctostaphylos nevadensis WoodlandG2 NatureServe
Abies grandis / Chrysolepis chrysophylla ForestG1 NatureServe
Abies grandis / Cornus nuttallii - Acer glabrum ForestG1 NatureServe
Abies grandis / Holodiscus discolor ForestG2 NatureServe
Abies grandis - Picea engelmannii / Maianthemum stellatum ForestG2 NatureServe
Abies grandis / Polemonium pulcherrimum ForestG3 NatureServe
Abies grandis - Pseudotsuga menziesii / Trientalis borealis ssp. latifolia ForestG3 NatureServe
Abies grandis / Symphoricarpos albus ForestG3 NatureServe
Abies grandis - Thuja plicata / Achlys triphylla ForestG2 NatureServe
Abies grandis - Tsuga heterophylla / Clintonia uniflora ForestG2 NatureServe
Abies grandis / Vaccinium membranaceum - Achlys triphylla ForestG2 NatureServe
Abies lowiana - Pinus contorta / Carex inops ssp. inops - Achnatherum occidentale ForestG3 NatureServe
State Conservation Ranks (2)

Subnational conservation status ranks (S-ranks) assigned by Natural Heritage Programs in each state where this ecosystem occurs. S1 indicates critically imperiled at the state level, S2 imperiled, S3 vulnerable, S4 apparently secure, and S5 secure. An ecosystem may be globally secure but imperiled in specific states at the edge of its range.

StateS-Rank
ORSNR
WASNR
Roadless Areas (42)

Inventoried Roadless Areas where this ecosystem is present, identified from LANDFIRE 2024 Existing Vegetation Type spatial analysis. Coverage indicates the proportion of each area occupied by this ecosystem type.

Oregon (11)

AreaForestCoverageHectares
Metolius BreaksDeschutes National Forest33.7%1,520.82
Badger CreekMt. Hood National Forest27.6%94.32
Mt. JeffersonDeschutes National Forest26.3%242.46
Twin LakesMt. Hood National Forest9.8%239.94
Mt. Jefferson AdditionMt. Hood National Forest9.4%6.12
Mt. Hood AdditionsMt. Hood National Forest4.8%256.23
Salmon - HuckleberryMt. Hood National Forest2.9%208.26
Wind CreekMt. Hood National Forest2.8%61.38
Three SistersDeschutes National Forest2.1%64.89
BearwallowsDeschutes National Forest1.7%49.86
Roaring RiverMt. Hood National Forest1.0%108.72

Washington (31)

AreaForestCoverageHectares
QuartzWenatchee National Forest64.3%2,224.62
Blue SlideWenatchee National Forest52.1%3,693.42
TaneumWenatchee National Forest49.5%5,239.71
Rock CreekWenatchee National Forest42.1%5,487.75
Wodouglas Adj.Wenatchee National Forest39.5%2,876.85
Goat Rocks AdjWenatchee National Forest35.6%880.2
Twin LakesWenatchee National Forest31.3%2,853.18
TeanawayWenatchee National Forest29.7%8,757.72
Norse PeakWenatchee National Forest26.8%1,103.58
NaneumWenatchee National Forest24.6%448.65
Lion RockWenatchee National Forest23.7%449.73
ManastashWenatchee National Forest23.6%1,067.22
Nason RidgeWenatchee National Forest20.6%1,611.09
Gotchen CreekGifford Pinchot National Forest20.0%607.23
Devils GulchWenatchee National Forest17.9%1,767.24
Canyon CreekWenatchee National Forest17.1%552.51
Alpine Lakes Adj.Wenatchee National Forest16.0%3,703.14
Thorp Mtn.Wenatchee National Forest13.8%1,267.2
EntiatWenatchee National Forest12.2%3,579.66
Stormy Mtn.Wenatchee National Forest8.7%1,149.3
Slide RidgeWenatchee National Forest5.4%248.4
Hungry RidgeOkanogan National Forest5.1%178.29
Black CanyonOkanogan National Forest5.0%194.4
Heather LakeWenatchee National Forest4.5%194.04
ChelanWenatchee National Forest4.1%1,230.39
South RidgeOkanogan National Forest3.0%75.69
Myrtle LakeWenatchee National Forest3.0%136.62
SawtoothOkanogan National Forest2.0%985.41
Big Lava BedGifford Pinchot National Forest1.6%122.22
Pasayten RimOkanogan National Forest1.5%101.7
Liberty BellOkanogan National Forest1.1%501.3
Methodology and Data Sources

Ecosystem classification: Ecosystems are classified using the LANDFIRE 2024 Existing Vegetation Type (EVT) layer, mapped to NatureServe Terrestrial Ecological Systems via a curated crosswalk. Each EVT is linked to the USNVC (U.S. National Vegetation Classification) hierarchy through pixel-level co-occurrence analysis of LANDFIRE EVT and NatureServe IVC Group rasters across all roadless areas.

Vegetation coverage: Coverage percentages and hectares are derived from zonal statistics of the LANDFIRE 2024 EVT raster intersected with roadless area boundaries.

Ecosystem narratives and community species: Sourced from the NatureServe Explorer API, representing professional ecological assessments of vegetation composition, environmental setting, dynamics, threats, and characteristic species assemblages.

IVC hierarchy: The International Vegetation Classification hierarchy is sourced from the USNVC v3.0 Catalog, providing the full classification from Biome through Association levels.

Component associations: Plant community associations listed as components of each NatureServe Ecological System. Association data from the NatureServe Explorer API.

State ranks: Conservation status ranks assigned by NatureServe member programs in each state where the ecosystem occurs.