LOCATION MCCLOUD AK
Established Series
Rev. DKS/DKM/DLM
05/2022
MCCLOUD SERIES
Depth class: moderately deep
Drainage class: well drained
Parent material: loess overlying weathered granite bedrock
Landform: hillsides, mountainsides, and ridge tops
Slopes: 0 to 45 percent
Mean annual precipitation: about 12 inches, 305 mm
Mean annual temperature: about 25 degrees F., -4 C.
TAXONOMIC CLASS: Coarse-loamy, mixed, superactive Typic Dystrocryepts
TYPICAL PEDON: McCloud silt loam - on a slope of 13 percent under paper birch, white spruce, and quaking aspen forest at 1250 feet elevation. (All colors are for moist soil unless noted)
Oe--0 to 2 inches, (0 to 4 cm); dark brown (7.5YR 3/2); moderately decomposed plant material; common very fine and fine, and few coarse roots; strongly acid (pH 5.2); clear smooth boundary. (1 to 6 inches thick)
E--2 to 3 inches, (4 to 8 cm); dark gray (7.5YR 4/1); silt loam; weak fine granular structure; friable, slightly sticky and nonplastic; few fine, medium, and coarse roots roots; strongly acid (pH 5.5); clear wavy boundary. (0 to 3 inches thick)
Bw--3 to 5 inches, (8 to 13 cm); dark yellowish brown (10YR 4/4); silt loam; weak medium platy structure; friable, slightly sticky and nonplastic; few fine and medium roots; 5 percent gravel; moderately acid (pH 5.7); gradual wavy boundary. (2 to 8 inches thick)
BC--5 to 20 inches, (13 to 50 cm); olive brown (2.5Y 4/4) and dark yellowish brown (10YR 4/4); silt loam; weak medium platy structure; friable, slightly sticky and nonplastic; 10 percent gravel; moderately acid (pH 5.7); gradual wavy boundary. (Combined thickness of the Bw and the BC is 9 to 18 inches thick)
C--20 to 29 inches, (50 to 74 cm); olive brown (2.5Y 4/4); silt loam; weak medium platy structure; friable, slightly sticky and nonplastic; 10 percent gravel; moderately acid (pH 5.7); gradual smooth boundary. (10 to 24 inches thick)
2Cr--29 to 72 inches, (74 to 183 cm); weathered granite bedrock
TYPE LOCATION: Fort Wainwright Soil Survey Area, Alaska; about 6 miles west of Eielson AFB; in the NE 1/4 of the NE 1/4, section 13, T. 3 S.., R. 4 E.; Big Delta C6 1:63,360 quad; Fairbanks Meridian; UTM north 7170652 and UTM east 507211, zone 6.
RANGE IN CHARACTERISTICS:
Particle-size control (section weighted average):
Percent clay in the control section: 3 to 14 percent
Total coarse fragments in the control section: 0 to 20 percent
Soil moisture regime: udic
Mean annual soil temperature: 26 degrees F., 50 cm
Thickness of name of organic materials: 1 to 6 inches, 2 to 15 cm
Texture of the loess mantle: silt loam
Texture of the loess mixed with residuum substratum: silt loam, loam or gravelly loam
Texture of the paralithic underlying layer: weathered granite bedrock
Percent clay in the loess mantle: 3 to 14 percent
Percent clay in the loess mixed with residuum substratum: 3 to 14 percent
Total coarse fragments in the Loess mantle: 0 to 10 percent
Total coarse fragments in the loess mixed with residuum substratum: 0 to 20 percent
Thickness of ochric epipedon 1 to 3 inches, 2 to 8 cm
Thickness of cambic horizon 2 to 20 inches, 5 to 50 cm
Depth to paralithic contact: 20 to 30 inches, 50 to 76 cm
O horizon:
Matrix color: hue of 5YR to 10YR; value of 2 or 3; chroma of 2 or 3
Texture: slightly or moderately decomposed plant material
Reaction class: very strongly or strongly acid
E horizon:
Matrix color: hue of 7.5YR or 10YR; value of 3 or 4; chroma of 1 or 2
Reaction class: strongly acid or moderately acid
Bw horizon:
Matrix color: hue of 7.5YR or 10YR; value of 3 to 5; chroma of 3 to 6
Coarse fragments: Total coarse fragments 0 to 10 percent
Reaction class: strongly acid or moderately acid
BC horizon:
Matrix color: hue of 10YR or 2.5Y; value of 3 or 4; chroma of 3 or 4
Texture: silt loam or loam
Coarse fragments: Total coarse fragments 0 to 10 percent
Reaction class: strongly acid or moderately acid
C horizon:
Matrix color: hue of 10YR to 5Y; value of 3 or 4; chroma of 3 or 4
Texture: silt loam, loam or gravelly loam
Coarse fragments: Total coarse fragments 0 to 20 percent
Reaction class: strongly acid to moderately acid
COMPETING SERIES: These are the
Koyukuk, and
Steese series. Koyukuk soils are formed in very deep silty materials. Steese soils are high in mica and overlie schist bedrock at depths of 20 to 40 inches.
GEOGRAPHIC SETTING:
Parent material: loess mantle over moderately deep, partially weathered granite bedrock
Landform: backslopes, shoulders, and summits of hills and low mountains
Slope: 0 to 45 percent
Mean annual temperature: 23 to 28 degrees F., -5 to -2 C.
Mean annual precipitation: 10 to 15 inches, 250 to 380 mm
GEOGRAPHICALLY ASSOCIATED SOILS: These include the
Angel,
Gilmore and
Steese series. Angel soils which are less than 20 inches thick over weathered granitic bedrock. Gilmore soils which are less than 20 inches thick over weathered schist bedrock. Steese soils which are 20 to 40 inches thick over weathered schist bedrock.
DRAINAGE AND PERMEABILITY: well drained, moderate to rapid runoff, saturated hydraulic conductivity is moderately high in the loamy surface mantle and very slow in the granitic bedrock.
.
USE AND VEGETATION: These soils are used for military training, roadfill, recreation, water supply, and wildlife habitat. Most areas are in native forest consisting of paper birch, white spruce, black spruce, and quaking aspen.
DISTRIBUTION AND EXTENT: MLRA 231, Interior Alaska Highlands,, The series is of moderate extent.
SOIL SURVEY REGIONAL OFFICE (SSRO) RESPONSIBLE: WASILLA, ALASKA
SERIES ESTABLISHED: Manley Hot Springs Area, Alaska. 1967. (Source of name is McCloud Creek)
REMARKS: Diagnostic features and horizons recognized in this profile include:
Ochric Epipedon: from 2 to 3 inches, 5 to 8 cm.
Cambic Horizon: from 3 to 20 inches, 8 to 50 cm.
Paralithic Contact: from 29 to 72 inches, 74 to 183 cm.
weighted average particle size class of coarse-loamy: from 12 to 29 inches, 30 to 74 cm.
Temperature regime: cryic 25 F., -4 C.
Moisture regime: udic
ADDITIONAL DATA:
National Cooperative Soil Survey
U.S.A.