LOCATION MESAHCHIE               WA

Established Series
Rev. CAB/SBC
06/2011

MESAHCHIE SERIES

The Mesahchie series consists of very deep, well drained soils formed in volcanic ash and reworked glacial drift over glacial drift on valley walls, debris cones, fan terraces, and alluvial fans. Slopes are 25 to 65 percent on valley walls and debris cones and 5 to 15 percent on fan terraces and alluvial fans. The mean annual precipitation is about 1,450 millimeters. The mean annual temperature is about 6 degrees C.

TAXONOMIC CLASS: Loamy-skeletal, isotic, frigid Andic Humixerepts

TYPICAL PEDON: Mesahchie gravelly ashy fine sandy loam, on a valley wall landform with a southeast facing slope of 55 percent at 800 meters elevation under an open canopy of coniferous forest vegetation. When described on October 12, 2006 the soil was dry throughout. (Colors are for moist soil unless otherwise noted.)

Oi--0 to 2 cm; slightly decomposed plant material; abrupt wavy boundary.

A1--2 to 20 cm; very dark brown (10YR 2/2) gravelly ashy fine sandy loam, dark grayish brown (10YR 4/2) dry; weak medium subangular blocky structure; soft, very friable, nonsticky, nonplastic; common very fine and fine roots and few medium roots throughout; 5 percent fine gravel, 10 percent medium and coarse gravel, and 5 percent cobbles; very strongly acid (pH 5.0); clear wavy boundary.

A2--20 to 44 cm; very dark brown (10YR 2/2) gravelly ashy sandy loam, dark grayish brown (10YR 4/2) dry; weak medium subangular blocky structure; soft, very friable, nonsticky, nonplastic; common very fine, fine, and medium roots and few coarse roots throughout; 5 percent fine gravel, 10 percent medium and coarse gravel, and 5 percent cobbles; strongly acid (pH 5.3); clear wavy boundary.

A3--44 to 74 cm; very dark brown (10YR 2/2) very cobbly ashy sandy loam, dark grayish brown (10YR 4/2) dry; weak fine subangular blocky structure; soft, very friable, nonsticky, nonplastic; common very fine and few fine, medium, and coarse roots throughout; 10 percent fine gravel, 15 percent medium and coarse gravel, and 20 percent cobbles; strongly acid (pH 5.5); abrupt wavy boundary.

2BC--74 to 96 cm; dark olive brown (2.5Y 3/3) very gravelly sandy loam, light olive brown (2.5Y 5/3) dry; weak medium subangular blocky structure; soft, very friable, nonsticky, nonplastic; 10 percent fine gravel, 15 percent medium and coarse gravel, and 10 percent cobbles; moderately acid (pH 5.8); clear wavy boundary.

2C--96 to 152 cm; very dark grayish brown (2.5Y 3/2) loamy sand, grayish brown (2.5Y 5/2) dry; single grain; loose, nonsticky, nonplastic; 15 percent fine gravel, 15 percent medium and coarse gravel, and 15 percent cobbles; moderately acid (pH 6.0).

TYPE LOCATION: North Cascades National Park, Chelan County, Washington; 761 meters east and 374 meters north of SW corner of Section 13, T34N, R14E Willamette Meridian; Goode Mountain, Washington USGS quadrangle; 48 degrees 35 minutes 48 seconds north latitude, 120 degrees 55 minutes 41 seconds west longitude; NAD83; UTM 653260 meters E, 5366155 meters N, zone 10N.

RANGE IN CHARACTERISTICS:
Mean annual soil temperature: 6 to 8 degrees C. Frigid soil temperature regime.
Soil moisture control section: dry for 60 to 90 consecutive days from June to October. Xeric soil moisture regime.
Thickness of volcanic ash mantle: 18 to 35 centimeters
Thickness of umbric epipedon: 25 to 85 centimeters
Rock fragment roundness classes: rounded, subrounded, subangular

A horizons:
Hue - 10 YR
Value - 2 to 3 moist, 3 to 5 dry
Chroma - 1 to 3 moist or dry
Fine earth texture - ashy FSL, ashy SL, or ashy COSL
Rock fragments - 10 to 60 percent total
5 to 35 percent gravel
5 to 20 percent cobbles
0 to 30 percent stones
Clay content - 3 to 8 percent
Volcanic glass - 5 to 30 percent
Reaction - very strongly acid to moderately acid
Thickness - 25 to 85 centimeters

Bw horizons are sometimes present with thickness ranging up to 50 cm, textures of ashy SL or ashy COSL, reaction of strongly acid or moderately acid, hue of 10YR, moist value of 3 or 4, and moist chroma of 3 or 4.

2BC horizon:
Hue -2.5Y or 10YR
Value - 3 to 5 moist, 4 to 6 dry
Chroma - 2 to 4 moist or dry
Fine earth texture - SL, COSL, or LS
Rock fragments - 35 to 60 percent total
25 to 40 percent gravel
10 to 20 percent cobbles
0 to 10 percent stones
Clay content - 1 to 6 percent
Volcanic glass - 0 to 20 percent
Reaction - strongly to slightly acid
Thickness - 20 to 70 centimeters

2C horizon:
Hue -2.5Y or variegated
Value - 3 to 5 moist, 5 or 6 dry
Chroma - 2 to 4 moist or dry
Fine earth texture - LS or LCOS
Rock fragments - 30 to 65 percent total
25 to 45 percent gravel
10 to 30 percent cobbles
0 to 10 percent stones
Clay content - 0 to 6 percent
Volcanic glass - 0 to 20 percent
Reaction - moderately to slightly acid

COMPETING SERIES: These are the Bertolotti, Cliffdell, Deroux, Goode, Littlejohn, Mountaineer, Pheeney, Pitcher, Roxer, Scotties, and Umpa series. Bertolotti soils lack an umbric epipedon and contain angular gneiss and granitic rock fragments. Cliffdell soils have 10 to 18 percent clay in the particle-size control section, and are dry for 45 to 60 consecutive days in the moisture control section. Deroux, Littlejohn, Mountaineer, Pheeney, and Umpa soils are moderately deep to a lithic contact. Goode soils lack an umbric epipedon. Pitcher soils are dry for 45 to 60 consecutive days in the moisture control section, contain angular rock fragments of extrusive igneous origin, and lack an umbric epipedon. Roxer soils lack an umbric epipedon and have 7 to 10 percent clay in the particle-size control section. Scotties soils lack an umbric epipedon and are deep to a lithic contact.

GEOGRAPHIC SETTING: The Mesahchie soils are on valley walls, debris cones, alluvial fans, and fan terraces at elevations of 365 to 1100 meters. Slopes are 5 to 65 percent. These soils formed in mixed volcanic ash and reworked glacial drift over glacial drift. The climate consists of cool, dry summers and cold, wet winters. Mean annual precipitation ranges from 600 to 1,600 millimeters, and mean annual air temperature ranges from 5 to 10 degrees C. Frost free season is 70 to 100 days.

GEOGRAPHICALLY ASSOCIATED SOILS: These are the Goode, Inspiration, and Lyall series. Goode soils are on the same landforms under thick coniferous vegetation cover and lack an umbric epipedon. Inspiration soils are on stable portions of valley walls and have andic soil properties greater than 36 cm deep. Lyall soils are on the least stable portions of debris cones, alluvial fans, and fan terraces and lack andic soil properties.

DRAINAGE AND SATURATED HYDRAULIC CONDUCTIVITY: Well drained; high to very high saturated hydraulic conductivity.

USE AND VEGETATION: Used for watershed, recreation, woodland, and wildlife habitat. Potential natural vegetation consists of Douglas-fir and ponderosa pine with an understory of fireweed, birchleaf spirea, Douglas maple, pachistima, serviceberry, oceanspray, and baldhip rose.

DISTRIBUTION AND EXTENT: Eastern slopes of the North Cascade Mountains, Washington. MLRA 3. Series is of moderate extent.

MLRA SOIL SURVEY REGIONAL OFFICE (MO) RESPONSIBLE: Portland, Oregon

SERIES ESTABLISHED: North Cascades National Park Service Complex soil survey, Washington, 2011.

REMARKS: Diagnostic horizons and features recognized in this pedon are:
Particle-size control section: 27 to 102 centimeters (A1, A2, A3, 2BC, and the upper 6 cm of the 2C)
Umbric epipedon: 2 to 74 centimeters (A1, A2, and A3 horizons)
Andic soil properties: 2 to 20 centimeters (A1 horizon)
Cambic horizon: 74 to 96 centimeters (2BC horizon)
Lithologic discontinuity: 74 centimeters

The A2 and A3 horizons have ashy textural modifiers but do not meet the criteria for andic soil properties.

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National Cooperative Soil Survey
U.S.A.