LOCATION MARBLECREEK ID

Established Series
Rev. CJW-BDG-EMM
07/2013

MARBLECREEK SERIES

The Marblecreek series consists of very deep, well drained soils on mountains. They formed in material weathered from schist and quartzite bedrock with a mantle of volcanic ash and loess. Saturated hydraulic conductivity is moderately high. Slope ranges from 15 to 80 percent. The average annual air temperature is about 6.7 degrees C and the average annual precipitation is about 950 mm.

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

TYPICAL PEDON: Marblecreek gravelly ashy silt loam, forest; on southeast-facing slope of 65 percent at 1,220 meters elevation. When described on September 26, 1982, the soil was moist throughout. (Colors are for dry soil unless otherwise noted.)

Oi--0 to 1 cm; slightly decomposed needles, leaves, and twigs.

Oe--1 to 4 cm; decomposed organic matter mixed with Mt. St. Helens volcanic ash. (combined thickness of O horizons is 0 to 4 cm thick)

A--4 to 13 cm; brown (10YR 5/3) gravelly ashy silt loam, dark brown (10YR 3/3) moist; weak fine subangular blocky structure parting to weak fine and medium granular; soft, very friable, nonsticky and slightly plastic; many very fine, fine, and medium roots; many very fine tubular pores; 25 percent gravel; neutral (pH 7.0); clear wavy boundary. (5 to 10 cm thick)

Bw1--13 to 33 cm; light yellowish brown (10YR 6/4) gravelly ashy silt loam, dark yellowish brown (10YR 4/4) moist; weak fine and medium subangular blocky structure; soft, very friable, nonsticky and slightly plastic; many very fine, fine, medium and few coarse roots; many very fine and fine tubular pores; 25 percent gravel, 5 percent cobbles; neutral (pH 6.8); abrupt wavy boundary. (13 to 23 cm thick)

2Bw2--33 to 68 cm; very pale brown (10YR 7/4) very gravelly sandy loam, yellowish brown (10YR 5/4) moist; weak fine subangular blocky structure; slightly hard, friable, nonsticky and slightly plastic; many very fine, fine, and few medium and coarse roots; many very fine and fine tubular and irregular pores; few faint clay films lining pores; 40 percent gravel, 10 percent cobbles; slightly acid (pH 6.2); gradual wavy boundary. (15 to 80 cm inches thick)

2BC--68 to 115 cm; pink (7.5YR 7/4) extremely gravelly sandy loam, brown (7.5YR 5/4) moist; weak fine subangular blocky structure; soft, very friable, nonsticky and nonplastic; common very fine and fine roots; many very fine and fine irregular pores; many very fine mica flakes; 50 percent gravel, 20 percent cobbles; slightly acid (pH 6.5); gradual wavy boundary. (0 to 68 cm thick)

2C--115 to 155 cm; pink (7.5YR 7/4) extremely cobbly loamy sand, brown (7.5YR 5/4) moist; massive; soft, very friable, nonsticky and nonplastic; few very fine and fine roots; many very fine and fine irregular pores; many very fine mica flakes; 45 percent gravel, 45 percent cobbles; slightly acid (pH 6.5).

TYPE LOCATION: Shoshone County, Idaho; about 2 miles southeast of the community of Herrick, about 1,750 feet west and 2,000 feet north of the southeast corner of sec. 16, T. 45. N., R. 3 E. Latitude -47 degrees, 14 minutes, 39 seconds North; Longitude - 116 degrees, 04 minutes, 50 seconds West; USGS Marble Mountain quadrangle.

RANGE IN CHARACTERISTICS:

Soil moisture - usually dry for 30 to 40 consecutive days August and September, moist mid-September through July (Udic moisture regime)
Average annual soil temperature - 6.1 to 7.8 degrees C
Average summer soil temperature - 9.4 to 11.7 degrees C with an O horizon (frigid temperature regime)
Depth to bedrock - greater than 150 cm
Volcanic ash mantle - 23 to 33 cm thick
Volcanic glass content - 30 to 65 percent
Acid-oxalate extractable Al + 1/2 Fe - 1.0 to 3.0 percent

A horizon
Hue - 10YR to 7.5YR, dry or moist
Value - 5 or 6 dry, 3 or 4 moist
Chroma - 2 to 4, dry or moist
Texture - ashy silt loam or ashy loam
Clay content - 3 to 10 percent
Rock fragments - 0 to 30 percent gravel
Bulk density - 0.65 to 0.95 g/cc
Reaction - moderately acid to neutral

Bw horizon
Value - 5 or 6 dry, 3 or 4 moist
Chroma - 3 or 4 moist
Texture - ashy silt loam or ashy loam
Clay content - 3 to 12 percent
Rock fragments - 0 to 30 percent gravel, 0 to 15 percent cobbles, 0 to 30 percent total fragments
Bulk density - 0.65 to 0.95 g/cc
Reaction - moderately acid to neutral

2Bw horizon
Hue - 10YR or 7.5YR dry or moist
Value - 5 to 7 dry, 3 to 6 moist
Chroma - 3 or 4 dry or moist
Texture - sandy loam, loam, or fine sandy loam
Clay content - 3 to 17 percent
Rock fragments - 25 to 55 percent gravel, 0 to 25 percent cobbles, 30 to 50 percent total fragments
Reaction - moderately acid or slightly acid

2C and 2BC horizons
Hue - 10YR or 7.5YR, dry or moist
Value - 6 to 8 dry, 5 to 7 moist
Chroma - 2 to 4 dry, 2 to 6 moist
Texture - sandy loam, loamy sand, or fine sandy loam
Clay content - 0 to 12 percent
Coarse fragments - 35 to 90 percent gravel, 0 to 20 percent cobbles, 35 to 90 percent total fragments
Reaction - moderately acid or slightly acid

COMPETING SERIES: This is the Pasturecreek series.

Paturecreek (OR) - formed in volcanic ash and loess over colluvium from argillite, metavolcanic rocks or rhyolite

GEOGRAPHIC SETTING: Marblecreek soils are on east, west, and south aspects of mountains. Slopes range from 15 to 80 percent. These soils formed in material weathered from schist and quartzite bedrock, with a mantle of volcanic ash and loess. Elevations range from 610 to 1585 meters. The average annual air temperature ranges from 5.0 to 7.8 degrees C, and average annual precipitation is 750 to 1600 mm. The average frost-free period is from 50 to 110 days.

GEOGRAPHICALLY ASSOCIATED SOILS: These are the Blackprince, Bouldercreek, Jacot, and Nakarna soils. Blackprince soils are on south-facing foothills and have paralithic bedrock at depths of 50 to 100 cm. Bouldercreek soils are on north-facing mountain slopes and are ashy over loamy-skeletal. Jacot soils are on north-facing foothills and are ashy over loamy. Nakarna soils are on north-facing mountain slopes and are ashy over loamy.

DRAINAGE AND SATURATED HYDRAULIC CONDUCTIVITY: Well drained; medium to rapid runoff; moderately high saturated hydraulic conductivity in the volcanic as mantle, and high to very high saturated hydraulic conductivity in the substratum.

USE AND VEGETATION: These soils are used for timber production, livestock grazing, recreation, wildlife habitat, and watershed. Potential natural vegetation is mainly grand fir, western larch, Douglas-fir, western white pine, and ponderosa pine, with an understory of queencup beadlily, longtube twinflower, myrtle pachystima, goldthread, common snowberry, piper anemone, Columbia brome, American trailplant, and sedge.

DISTRIBUTION AND EXTENT: Northern Idaho. MLRA 43A. This soil is moderately extensive.

MLRA SOIL SURVEY REGIONAL OFFICE (MO) RESPONSIBLE: Bozeman, Montana

SERIES ESTABLISHED: Shoshone County, Idaho, 1993.

REMARKS: Diagnostic horizons and features recognized in this pedon are:

Ochric epipedon - the zone from 0 to 13 cm (Oi, Oe and A horizons)
Cambic horizon - the zone from 13 to 68 cm (Bw1 and 2Bw2 horizon)
Volcanic ash mantle - the zone from 4 to 33 cm (A and Bw1 horizons)
Particle-size control section - the zone from 29 to 104 cm (part of the Bw1, 2Bw2, and part of the 2BC horizon)

10/2012 Marblecreek is reclassified from Dystrudepts to Eutrudepts great group. This reflects the preponderance of lab data regarding base saturation in soils sampled on similar parent materials in the MLRA.

National Cooperative Soil Survey
U.S.A.