LOCATION MANTREE                 CA

Established Series
SMM/AGB/TKK/JW
09/2018

MANTREE SERIES

The Mantree series consists of very deep, well drained soils formed in colluvium from andesitic tuff breccia over residuum weathered from intrusive igneous rock. The Mantree soils are on mountainflanks and mountaintops below lahars. Slopes range from 3 to 60 percent. The mean annual precipitation is about 1240 mm and the mean annual air temperature is about 13 degrees C.

TAXONOMIC CLASS: Fine-loamy, isotic, mesic Andic Palexeralfs

TYPICAL PEDON: Mantree ashy loam on a northeast facing, linear, 30 percent slope, under cover of white fir, Douglas fir, and pacific yew at an elevation of 1120 meters. (Colors are for dry soils unless otherwise noted. When described on June 7th, 2007 the soil was moist throughout.)

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

Oe--2 to 4 cm; moderately decomposed plant material; abrupt smooth boundary. (Combined thickness of Oi and Oe [where present] horizons is 3 to 8 cm)

A--4 to 10 cm; reddish brown (5YR 5/4) ashy loam, dark reddish brown (2.5YR 3/3) moist; 52 percent sand; 9 percent clay; weak fine subangular blocky structure; soft, friable, nonsticky, slightly plastic; common very fine to medium roots throughout; many very fine and fine irregular pores; 2 percent subrounded strongly cemented andesite gravel; slightly acid (pH 6.2); clear smooth boundary.

BA--10 to 36 cm; red (2.5YR 4/6) ashy loam, dark reddish brown (2.5YR 3/4) moist; 51 percent sand; 11 percent clay; weak fine and medium subangular blocky structure; soft, friable, slightly sticky, slightly plastic; common very fine to coarse roots throughout; many very fine and fine irregular pores; 2 percent subrounded strongly cemented andesite gravel; moderately acid (pH 6.0); clear wavy boundary. (Combined thickness of A and BA horizons is 10 to 30 cm)

Bt1--36 to 59 cm; red (2.5YR 5/6) loam, reddish brown (2.5YR 4/4) moist; 47 percent sand; 18 percent clay; moderate medium subangular blocky structure; hard, friable, slightly sticky, slightly plastic; common very fine to coarse roots throughout; many very fine and fine irregular pores; 10 percent faint clay films on all faces of peds; 10 percent subrounded strongly cemented andesite gravel; moderately acid (pH 5.8); clear wavy boundary.

Bt2--59 to 89 cm; reddish yellow (5YR 6/6) gravelly loam, yellowish red (5YR 4/6) moist; 48 percent sand; 20 percent clay; moderate medium and coarse subangular blocky structure; hard, firm, slightly sticky, moderately plastic; few very fine to coarse roots throughout; many very fine and fine irregular and few fine tubular pores; 30 percent distinct clay films on all faces of peds; 3 percent fine weathered biotite mica flakes; 15 percent subangular strongly cemented andesite gravel, 2 percent subangular strongly cemented andesite cobbles; moderately acid (pH 6.0); gradual wavy boundary. (Combined thickness of upper Bt horizons is 40 to 80 cm)

Bt3--89 to 120 cm; reddish yellow (5YR 6/6) clay loam, yellowish red (5YR 4/6) moist; 32 percent sand; 30 percent clay; strong coarse subangular blocky structure; very hard, very firm, slightly sticky, moderately plastic; few very fine to medium roots throughout; common very fine and fine irregular and few fine tubular pores; 20 percent distinct clay films; 3 percent fine weathered biotite mica flakes; moderately acid (pH 6.0); gradual wavy boundary.

Bt4--120 to 152 cm; yellowish red (5YR 5/8) loam, yellowish red (5YR 4/6) moist; 44 percent sand; 26 percent clay; strong coarse subangular blocky structure; very hard, firm, moderately sticky, moderately plastic; few very fine and fine roots throughout; common very fine and fine irregular pores; 10 percent faint clay films; 3 percent fine weathered biotite mica flakes; moderately acid (pH 6.0); gradual wavy boundary. (Combined thickness of lower Bt horizons is 40 to 80 cm)

BCt--152 to 175 cm; strong brown (7.5YR 5/6) loam, yellowish red (5YR 4/6) moist; 47 percent sand; 23 percent clay; moderate coarse subangular blocky structure; hard, firm, moderately sticky, moderately plastic; few very fine and fine roots throughout; common very fine and fine irregular pores; 2 percent faint clay films; 3 percent fine weathered biotite mica flakes; moderately acid (pH 5.8).

TYPE LOCATION: Calaveras County, California, approximately 1.7 km (1 mi) north-northwest of the summit of Buck Mountain; USGS 7.5 minute topographic quadrangle: Devils Nose, California; WGS84 38.389446 latitude and -120.379723 longitude; UTM zone 10 4252274 meters N 728855 meters E NAD83.

RANGE IN CHARACTERISTICS:

Soil temperature: The mean annual soil temperature at 50 cm is 13 to 15 degrees C and the difference between mean summer and mean winter soil temperature is greater than 6 degrees C. The soils have a mesic temperature regime.

Soil moisture: The soil moisture control section is dry in all parts from June to October. The soils have a xeric moisture regime.

Diagnostic Feature(s):
Ochric epipedon thickness: 5 to 40 cm
Argillic horizon thickness: 50 to >150 cm
Depth to paralithic contact: >150 cm

Particle size control section weighted averages:
Clay content: averages 18 to 30 percent clay
Rock fragments: 0 to 15 percent

A horizons
Hue: 5YR, 7.5YR
Value: 3 to 5 dry, 2.5 or 3 moist
Chroma: 2 to 4 dry, 2 or 3 moist
Texture: loam or sandy loam
Clay content: 10 to 18 percent
Rock fragments: 0 to 10 percent gravels
Reaction: moderately acid to neutral
Acid-oxalate extractable Al plus 1/2 Fe: 1 to 2 percent
Bulk density (33 kPa): 0.9 to 1.05 g/cc
NZ Phosphorus Retention: 75 to 100 percent

BA horizons
Hue: 5YR, 7.5YR
Value: 5 or 6 dry, 3 or 4 moist
Chroma: 4 or 6 dry, 3 or 4 moist
Texture: loam or sandy loam
Clay content: 10 to 18 percent
Rock fragments: 0 to 10 percent gravels
Reaction: moderately acid to neutral
Acid-oxalate extractable Al plus 1/2 Fe: 1 to 2 percent
Bulk density (33 kPa): 0.9 to 1.05 g/cc
NZ Phosphorus Retention: 75 to 85 percent

Bt horizons (upper)
Hue: 5YR, 2.5YR, 7.5YR
Value: 5 to 7 dry; 4 or 5 moist
Chroma: 4 to 6 dry or moist
Texture: loam, clay loam, sandy clay loam
Clay content: 18 to 40 percent
Rock fragments: 0 to 20 percent gravels
Reaction: moderately acid to neutral

Bt (lower) and BCt horizons
Hue: 7.5YR, 5YR
Value: 4 to 6 dry or moist
Chroma: 4 or 6 dry or moist
Texture: clay loam, sandy clay loam, loam
Clay content: 20 to 35 percent
Rock fragments: 0 to 5 percent gravels
Reaction: very strongly to moderately acid

COMPETING SERIES: These are the Wyntoon (MLRAs 21 and 22B) soils. Wyntoon soils formed in volcanic ash and alluvium derived from volcanic rocks are on hills or fan remnants, and have a mean annual soil temperature of 8 to 11 degrees C.

GEOGRAPHIC SETTING: The Mantree soils are on mountainflanks and mountaintops below lahars. Slopes range from 3 to 60 percent. These soils formed in colluvium from andesitic tuff breccia over residuum weathered from intrusive igneous rock. Elevation is 850 to 1300 meters. The climate is Mediterranean with warm, dry summers and cool, moist winters. The mean annual precipitation is 1100 to 1300 mm and the mean annual air temperature is 12 to 14 degrees C. The frost free season is 190 to 215 days.

GEOGRAPHICALLY ASSOCIATED SOILS: These are the Devilsnose, Holland, Lilygap, Musick, Redapple and Wukusick soils. Devilsnose, Lilygap and Redapple all occur on lahars. Devilsnose and Lilygap are medial in the upper part of the control section. Devilsnose soils occur on the middle to upper portions of mountainflanks and Lilygap soils occur on the lower portions. Redapple soils are fine and are on stable summits and backslopes. Holland, Musick and Wukusick occur on similar landform positions and also formed in intrusive igneous bedrock, but lack low bulk densities with oxalate-extractable Al+1/2Fe greater than 1.0 percent in the surface horizons. Holland soils occur on high hills, mountain slopes and canyons.

DRAINAGE AND PERMEABILITY: Well drained, moderately high saturated hydraulic conductivity.

USE AND VEGETATION: This soil is used for timber production, wildlife habitat, watershed, recreation and limited homesite development. Vegetation is Douglas fir, white fir, pacific yew, sugar pine, ponderosa pine, incense cedar, California black oak, deerbrush, whiteleaf manzanita, greenleaf manzanita, gray pinemat manzanita, and mountain misery.

DISTRIBUTION AND EXTENT: Sierra Nevada Mountains of California; MLRA 22A. The series is not extensive.

SOIL SURVEY REGIONAL OFFICE (SSRO) RESPONSIBLE: Davis, California

SERIES PROPOSED: Calaveras County, California. Series name is coined.

REMARKS:
Diagnostic horizons and features recognized in this pedon are:
Ochric Epipedon 0 to 36 cm
Argillic Horizon 36 to >175 cm
Bulk density (33 kPa) 0.9 to 1.0 g/cc in A and BA horizons
Acid-oxalate extractable Al + 1/2Fe 1 to 2 percent in A and BA horizons

Particle Size Control Section for this pedon: 36 to 86 cm.

ADDITIONAL DATA:
Pedon information for this type location only:
NASIS User Pedon ID: S08CA009003
Pedon Type: OSD pedon
Pedon Purpose: laboratory sampling site
Lab Source ID: SSL
Lab Pedon #: 08N0693

Soil classified using the 12th Edition of the Keys to Soil Taxonomy.

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National Cooperative Soil Survey
U.S.A.