LOCATION MOUNTWOW WA
Established Series
REV. SMB/PHR/MPR
03/2017
MOUNTWOW SERIES
Landscape--Cascade Mountains
Landform--swales, cirques, parklands
Slope--0 to 65 percent
Parent material--volcanic ash over colluvium
Mean annual precipitation--about 2500 mm
Mean annual air temperature--about 2 degrees C
Depth class--very deep
Drainage class--somewhat poorly drained
Soil moisture regime--aquic
Soil temperature regime--cryic
Soil moisture subclass--typic
TAXONOMIC CLASS: Medial, glassy, acid Thaptic Cryaquands
TYPICAL PEDON: Mountwow medial sandy loam in a meadow on a north-facing cirque with a slope of 2 percent and at an elevation of 1,805 m (When described on August 22, 2013, the soil was slightly moist throughout.)
Oi--0 to 2 cm; slightly decomposed plant material; many fine interstitial pores; very strongly acid (pH 4.5); abrupt wavy boundary
A--2 to 10 cm; medial sandy loam, grayish brown (10YR 5/2) dry, very dark grayish brown (10YR 3/2) moist; weak fine subangular blocky structure; soft, very friable, nonsticky and nonplastic; common very fine and few fine roots; common very fine and fine interstitial pores; strongly acid (pH 5.2); abrupt wavy boundary
Bw1--10 to 14 cm; paragravelly medial coarse sandy loam, brown (7.5YR 5/3) dry, dark brown (7.5YR 3/3) moist; weak fine subangular blocky structure; soft, very friable, nonsticky and nonplastic; common very fine roots; common very fine and fine interstitial pores; 10 percent fine pumice paragravel and 10 percent medium and coarse pumice paragravel; strongly acid (pH 5.2); abrupt wavy boundary
Bw2--14 to 26 cm; medial fine sandy loam, light brownish gray (10YR 6/2) dry, dark grayish brown (10YR 4/2) moist; weak fine subangular blocky structure; soft, very friable, nonsticky and nonplastic; few very fine roots; common very fine and fine interstitial pores; 10 percent fine pumice paragravel; strongly acid (pH 5.2); clear wavy boundary
Bw3--26 to 37 cm; medial loamy sand, very pale brown (10YR 7/4) dry, yellowish brown (10YR 5/4) moist; weak fine subangular blocky structure; soft, very friable, nonsticky and nonplastic; few very fine roots; common very fine and fine interstitial pores; 5 percent fine pumice paragravel and 5 percent medium and coarse pumice paragravel; strongly acid (pH 5.2); abrupt wavy boundary
Agb--37 to 44 cm; medial sandy loam, dark grayish brown (10YR 4/2) dry, very dark brown (10YR 2/2) moist; weak fine subangular blocky structure; soft, very friable, nonsticky and nonplastic; few very fine roots; common very fine and fine irregular pores; 2 percent gray (10YR 5/1) iron depletions in matrix and 4 percent dark reddish brown (5YR 3/4) masses of oxidized iron with diffuse boundaries along root channels; strongly acid (pH 5.2); abrupt wavy boundary
Bgb1--44 to 51 cm; paragravelly medial sandy loam, brown (7.5YR 5/4) dry, dark brown (7.5YR 3/4) moist; weak fine subangular blocky structure; soft, very friable, nonsticky and nonplastic; few very fine roots; common very fine and fine interstitial pores; 4 percent dark reddish brown (5YR 3/4) masses of oxidized iron with diffuse boundaries along root channels; 10 percent fine pumice paragravel and 10 percent medium and coarse pumice paragravel; strongly acid (pH 5.2); clear wavy boundary
Bgb2--51 to 60 cm; medial coarse sandy loam, brown (7.5YR 5/3) dry, dark brown (7.5YR 3/3) moist; weak fine subangular blocky structure; soft, very friable, nonsticky and nonplastic; few very fine roots; common very fine and fine interstitial pores; 4 percent dark reddish brown (5YR 3/4) masses of oxidized iron with diffuse boundaries along root channels; 10 percent fine pumice paragravel; strongly acid (pH 5.2); abrupt wavy boundary
Bgb3--60 to 66 cm; medial fine sandy loam, reddish yellow (7.5YR 7/6) dry, strong brown (7.5YR 5/6) moist; weak fine subangular blocky structure; soft, very friable, nonsticky and nonplastic; few very fine roots; common very fine and fine interstitial pores; 2 percent gray (10YR 5/1) iron depletions in matrix and 4 percent dark reddish brown (5YR 3/4) masses of oxidized iron with diffuse boundaries along root channels; strongly acid (pH 5.2); abrupt smooth boundary
2Agb2--66 to 85 cm; medial sandy loam, dark grayish brown (10YR 4/2) dry, very dark brown (10YR 2/2) moist; weak fine subangular blocky structure; soft, very friable, nonsticky and nonplastic; few very fine roots; common very fine and fine irregular pores; 2 percent gray (10YR 5/1) iron depletions in matrix and 4 percent dark reddish brown (5YR 3/4) masses of oxidized iron with diffuse boundaries along root channels; strongly acid (pH 5.4); abrupt wavy boundary
2Bgb4--85 to 120 cm; very gravelly medial sandy loam, yellowish brown (10YR 5/4) dry, dark yellowish brown (10YR 3/4) moist; weak fine subangular blocky structure; soft, very friable, nonsticky and nonplastic; few very fine roots; common very fine and fine interstitial pores; 2 percent gray (10YR 5/1) iron depletions in matrix and 4 percent dark reddish brown (5YR 3/4) masses of oxidized iron with diffuse boundaries along root channels; 15 percent fine andesite gravel, 15 percent medium and coarse andesite gravel, and 15 percent andesite cobbles; strongly acid (pH 5.4); clear wavy boundary
2Bgb5--120 to 150 cm; very gravelly medial sandy loam, yellowish brown (10YR 5/4) dry, dark yellowish brown (10YR 3/4) moist; weak fine subangular blocky structure; soft, very friable, nonsticky and nonplastic; few very fine roots; common very fine and fine interstitial pores; 2 percent gray (10YR 5/1) iron depletions in matrix and 4 percent dark reddish brown (5YR 3/4) masses of oxidized iron with diffuse boundaries along root channels; 15 percent fine andesite gravel, 15 percent medium and coarse andesite gravel, and 20 percent andesite cobbles; strongly acid (pH 5.4)
TYPE LOCATION: Pierce County, Washington, along Wonderland Trail on the Cowlitz Divide, between Nickel Creek and the Ohanapecosh River, about 10 km northwest of the Ohanapecosh Ranger Station in Mount Rainier National Park; about 300 m north and 710 m west of the southeast corner of section 1, T. 15 N., R. 9 E., Willamette Meridian; Chinook Pass, Washington, U.S. Geological Survey quadrangle; latitude 46.815208 degrees north, longitude -121.622868 degrees west, datum WGS 84 (coordinates determined with a GPS)
RANGE IN CHARACTERISTICS:
Mean annual soil temperature--1 to 5 degrees C
Depth to redoximorphic iron depletions--25 to 50 cm below the mineral soil surface
All mineral horizons
*Reaction--4.5 to 5.5
*Volcanic glass content--50 to 75 percent
*Ammonium oxalate Al plus 1/2 Fe--greater than 1.0 percent
Particle-size control section
*Clay content--1 to 10 percent
*Pararock and rock fragment content--5 to 35 percent total
O horizon
*In lieu of texture--slightly decomposed plant material, moderately decomposed plant material
*Thickness--0 to 10 cm
A horizon
*Hue--10YR, 7.5YR
*Value--2 or 3 moist, 3 to 5 dry
*Chroma--1 or 2 moist or dry
*Fine-earth texture--medial sandy loam, medial loamy sand
*Pararock fragment content--0 to 15 percent pumice paragravel
*Thickness--5 to 20 cm
Bw1 horizon
*Hue--7.5YR, 10YR
*Value--2 or 3 moist, 3 to 5 dry
*Chroma--2 to 4 moist or dry
*Fine-earth texture--medial coarse sandy loam, medial sandy loam, medial loamy coarse sand
*Pararock fragment content--15 to 30 percent pumice paragravel
*Thickness--3 to 15 cm
Bw2 horizon
*Hue--10YR, 7.5YR
*Value--2 to 4 moist, 4 to 6 dry
*Chroma--2 to 4 moist or dry
*Fine-earth texture--medial fine sandy loam, medial sandy loam, medial loamy fine sand
*Pararock fragment content--5 to 20 percent pumice paragravel
*Thickness--10 to 20 cm
Bw3 horizon
*Hue--7.5YR, 10YR, 5YR
*Value--3 to 6 moist, 5 to 8 dry
*Chroma--2 to 5 moist or dry
*Fine-earth texture--medial loamy sand, medial loamy coarse sand, medial coarse sandy loam
*Pararock fragment content--5 to 30 percent pumice paragravel
*Thickness--10 to 30 cm
Agb1 horizon
*Hue--10YR, 7.5YR
*Value--2 to 3 moist, 3 to 5 dry
*Chroma--1 to 3 moist or dry
*Fine-earth texture--medial sandy loam, medial loamy sand, medial coarse sandy loam
*Pararock fragment content--0 to 20 percent pumice paragravel
*Thickness--5 to 20 cm
Bgb1 horizon
*Hue--7.5YR, 5YR, 10YR
*Value--2 to 4 moist, 4 to 6 dry
*Chroma--2 to 4 moist or dry
*Fine-earth texture--medial sandy loam, medial loamy coarse sand, medial coarse sandy loam
*Pararock fragment content--15 to 30 percent pumice paragravel
*Thickness--5 to 20 cm
Bgb2 horizon
*Hue--7.5YR, 5YR, 10YR
*Value--3 or 4 moist, 4 to 6 dry
*Chroma--2 to 4 moist or dry
*Organic carbon content--less than 2.0 percent
*Fine-earth texture--medial coarse sandy loam, medial loamy coarse sand, medial sandy loam
*Pararock fragment content--5 to 30 percent pumice paragravel
*Thickness--5 to 20 cm
Bgb3 horizon
*Hue--7.5YR, 5YR, 10YR
*Value--4 to 6 moist, 6 to 8 dry
*Chroma--2 to 6 moist or dry
*Organic carbon content--less than 2.0 percent
*Fine-earth texture--medial fine sandy loam, medial loamy fine sand, medial sandy loam
*Pararock fragment content--0 to 20 percent pumice paragravel
*Thickness--5 to 20 cm
2Agb2 horizon
*Hue--10YR, 7.5YR
*Value--2 to 3 moist, 4 to 5 dry
*Chroma--1 to 3 moist or dry
*Organic carbon content--greater than 3.0 percent
*Fine-earth texture--medial fine sandy loam, medial loamy fine sand, medial sandy loam
*Rock fragment content--0 to 30 percent gravel
*Thickness--10 to 35 cm
2Bgb horizon
*Hue--10YR, 7.5YR
*Value--2 to 4 moist, 4 to 6 dry
*Chroma--2 to 4 moist or dry
*Fine-earth texture--medial sandy loam, medial loamy sand, medial fine sandy loam
*Rock fragment content--15 to 55 percent total, including 15 to 45 percent gravel, 0 to 25 percent cobbles, and 0 to 10 percent stones
*Combined thickness--40 to 80 cm
COMPETING SERIES: None
GEOGRAPHIC SETTING:
Elevation--1200 to 2500 m
Climate--cool, dry summers; cold, wet winters
Mean annual precipitation--1700 to 3600 mm
Mean annual air temperature--0 to 4 degrees C
Frost-free period--5 to 60 days
GEOGRAPHICALLY ASSOCIATED SOILS:
Littletahoma--no aquic conditions; in similar landform positions
Burroughs--lithic contact at a depth of 50 to 100 cm (moderately deep); no aquic conditions; on similar landforms with bedrock near surface
Tatoosh--lithic contact at a depth of 25 to 50 cm (shallow); no aquic conditions; on similar landforms with bedrock near surface
Chenuis--greater than 35 percent rock fragments, by weighted average, in particle-size control section; no aquic conditions; on steeper slopes of similar landforms; associated with talus fields
Wahpenayo--lithic contact at a depth of 50 to 100 cm (moderately deep); aquic conditions below a depth of 50 cm; on similar landforms with bedrock near surface
Ghost,
Meany,
Williwakas--aquic conditions within 25 cm of mineral soil surface; in gentler sloping positions and depressions that receive runoff from upslope areas
Mysticlake--no thaptic feature; on similar landforms under coniferous overstory
Unicornpeak,
Ipsut,
Owyhigh,
Tipsoo--albic and spodic horizons; similar landforms under coniferous overstory
DRAINAGE AND SATURATED HYDRAULIC CONDUCTIVITY:
Drainage class--somewhat poorly drained
Saturation in normal years--below a depth of 25 to 50 cm in April through June, below a depth of 100 to 180 cm in August through December
Saturated hydraulic conductivity (Ksat)--high or very high throughout
USE AND VEGETATION:
Use--wildlife habitat, recreation
Potential natural vegetation--Cascade huckleberry, Alaska huckleberry, pink mountain heather, white mountain heather, false hellebore, fleeceflower, alpine aster, leafy aster, western columbine, arctic lupine, Sitka valerian, common yarrow, smooth woodrush, American bistort, occasional scattered subalpine fir, mountain hemlock, and Alaska yellow-cedar
DISTRIBUTION AND EXTENT: Central Cascade Mountains, Washington; MLRA 3; moderate extent
MLRA SOIL SURVEY REGIONAL OFFICE (MO) RESPONSIBLE: Portland, Oregon
SERIES PROPOSED: Mount Rainier National Park, Pierce County, Washington; 2014; name from Mount Wow in Mount Rainier National Park
REMARKS:
Diagnostic horizons and other features in this pedon
*Particle-size control section--zone from 2 to 102 cm
*Ochric epipedon
*Cambic horizon--zone from 10 to 26 cm and from 37 to 150 cm
*Andic soil properties--zone from 2 to 150 cm
*Volcanic glass--zone from 2 to 150 cm
*Thaptic feature--zone from 66 to 85 cm
*Redoximorphic iron concentrations--zone from 37 to 150 cm
*Redoximorphic iron depletions with chroma of 2 or less--zone from 37 to 44 cm and from 60 to 150 cm
*Depth to lithologic discontinuity--66 cm
*Distinguishable tephra layers--Mount St. Helens Wn tephra (A horizon), Mount Rainier C tephra (Bw1 horizon), Mount St. Helens P tephra (Bw2 horizon), Mount St. Helens Yn tephra (Bw3 horizon), Mount Rainier F tephra (Bgb1 horizon), Mount Rainier D tephra (Bgb2 horizon), Mount Mazama O tephra (Bgb3 horizon)
12/2015--This official series description was updated according to SSR1 Technical Note 11--Content and Format of Official Series Descriptions (revised 12/2015). Most of the changes were in formatting; no major technical changes were made.
National Cooperative Soil Survey
U.S.A.