LOCATION SKALAN ID+WAEstablished Series
TAXONOMIC CLASS: Loamy-skeletal, isotic, mesic Vitrandic Haploxeralfs
TYPICAL PEDON: Skalan gravelly ashy loam, forested. (Colors are for dry soil unless otherwise noted.)
Oi--0 to 0.5 inches; undecomposed needles, twigs, leaves and cones.
Oe--0.5 to 2; partially decomposed needles, twigs, leaves and cones.
A--2 to 5 inches; dark grayish brown (10YR 4/2) gravelly ashy loam, very dark grayish brown (10YR 3/2) moist; moderate fine and medium granular structure; very soft, very friable, slightly sticky and slightly plastic; many very fine and fine, common medium and few coarse roots; common very fine and fine interstitial pores; 25 percent gravel; slightly acid (pH 6.3); clear wavy boundary. (2 to 9 inches thick)
Bt1--5 to 10 inches; brown (10YR 5/3) gravelly ashy loam, brown (7.5YR 4/2) moist; weak fine and medium, subangular blocky structure; soft, friable, slightly sticky and slightly plastic; many very fine and fine, common medium and few coarse roots; common very fine and fine interstitial pores; few faint clay films; 25 percent gravel; moderately acid (pH 5.8); abrupt wavy boundary. (3 to 6 inches thick)
Bt2--10 to 14 inches; yellowish brown (10YR 5/4) extremely gravelly clay loam, dark yellowish brown (10YR 4/4) moist; weak fine subangular blocky structure; slightly hard, friable, sticky and slightly plastic; common fine, few medium and coarse roots; common very fine and fine tubular and interstitial pores; few faint clay films on faces of peds; 75 percent gravel; moderately acid (pH 6.0); clear wavy boundary. (4 to 8 inches thick)
Bt3--14 to 20 inches; light yellowish brown (10YR 6/4) extremely gravelly loam, dark yellowish brown (10YR 4/4) moist; weak fine and medium subangular blocky structure; slightly hard, friable, sticky and slightly plastic; few fine, medium and coarse roots; common very fine and fine tubular pores; few faint clay films in pores; 75 percent gravel; moderately acid (pH 6.0); clear wavy boundary. (3 to 9 inches thick)
C--20 to 32 inches; light yellowish brown (10YR 6/4) extremely gravelly loam, dark yellowish brown (10YR 4/4) moist; massive; hard, friable, slightly sticky and slightly plastic; few medium and coarse roots; common very fine and fine tubular pores; 80 percent gravel; moderately acid (pH 6.0); clear wavy boundary. (9 to 12 inches thick)
R--32 inches; fractured gneiss.
TYPE LOCATION: Kootenai County, Idaho; 22 feet south of Post Falls, Mica Peak road and 0.4 miles east of intersection with Pleasant View road; in the SE1/4 NW1/4 section 9, T.50N., R.5W.
RANGE IN CHARACTERISTICS:
Depth to bedrock (lithic contact) 20 to 40 inches
Moisture control section (8 to 24 inches) moist early November to early July; dry July to October
Mean annual soil temperature 47 to 51 degrees F
Rock fragment content 25 to 80 percent, averaging more than 35 percent in the particle-size control section
Base saturation 50 to 75 percent in some or all parts of the soil above 30 inches
Volcanic ash influence 7 to 15 inches
Estimated properties of ash influence layer:
Volcanic glass content 5 to 25 percent
Acid oxalate extractable Al + Fe 0.4 to 1.0 percent
Moist bulk density 1.0 to 1.2 g/cc
15-bar water retention 5 to 10 percent (air-dried)
A horizon
Value - 3 to 5 dry, 2 or 3 moist
Chroma - 2 or 3
Texture - gravelly ashy loam, gravelly ashy silt loam
Clay content 10 to 25 percent
Gravel content 15 to 30 percent
BA horizon (present in some pedons)
Texture gravelly ashy loam, very gravelly ashy loam
Clay content 12 to 18 percent
Gravel content 15 to 35 percent
Bt1 horizon
Hue 10YR, 7.5 YR
Value 5 or 6 dry, 3 or 4 moist
Chroma 2 to 4, dry or moist
Texture ashy loam, ashy silt loam, loam, clay loam, sandy clay loam and is gravelly or very gravelly
Clay content 15 to 35 percent
Gravel content 25 to 60 percent
Reaction moderately acid or slightly acid
Bt2 and Bt3 horizons
Hue - 10YR, 7.5YR
Value - 5 or 6 dry, 3 or 4 moist
Chroma - 2 to 4, dry or moist
Texture loam, clay loam, sandy clay loam, and is very gravelly or extremely gravelly
Gravel content 35 to 75 percent
Cobble content 0 to 10 percent
Reaction moderately acid or slightly acid
C horizon
Hue 10YR, 7.5YR
Value 5 or 6 dry, 3 or 4 moist
Chroma 3 or 4, dry or moist
Texture loam, coarse sandy loam, clay loam, and is very gravelly or extremely gravelly
Gravel content 35 to 80 percent
Cobble content 0 to 5 percent
Reaction moderately acid or slightly acid
A Cr horizon is present in some pedons above the 2R
COMPETING SERIES: This is the Melder series. Melder soils are 40 to 60 inches to a lithic contact.
GEOGRAPHIC SETTING: Skalan soils are on undulating to very steep mountainous slopes. Elevations range from 1,800 to 3,500 feet. The soils are on all aspects at lower elevations and mainly on south and west slopes at the higher elevations. Skalan soils formed in material weathered from gneiss and other related metamorphic rocks, with an influence of volcanic ash and loess in the upper part. The climate is characterized by cool, moist winters and warm, dry summers. The mean annual precipitation is 18 to 27 inches. The mean January temperature is 28 degrees F. and the mean July temperature is 66 degrees F.. The mean annual temperature is 45 degrees to 49 degrees F. The frost-free season is 100 to 130 days.
GEOGRAPHICALLY ASSOCIATED SOILS: These are the Kruse, Lenz, Molly, Moscow, Schumacher, Spokane, Ulricher, and Vassar soils. Kruse and Schumacher soils are fine-loamy and are on mountain and foothill side slopes. Lenz and Spokane soils do not have argillic horizons and are on mountain and foothill side slopes. Moscow and Ulricher soils have less than 35 percent rock fragments in the particle-size control section. Moscow soils are on foot slopes, back slopes, and ridges of mountains. Ulricher soils are on mountains. Molly and Vassar soils have contrasting particle-size control sections. Molly soils are on rolling to very steep mountain side slopes. Vassar soils are on mountains.
DRAINAGE AND PERMEABILITY: Well drained; medium to very rapid runoff; moderate or moderately slow permeability.
USE AND VEGETATION: These soils are used mainly for grazing and timber production. The native vegetation is mainly ponderosa pine, bluebunch wheatgrass, snowberry and other short shrubs.
DISTRIBUTION AND EXTENT: Mountainous uplands in Northern Idaho and Eastern Washington. MLRA 43. This series is inextensive.
MLRA OFFICE RESPONSIBLE: Bozeman, Montana
SERIES ESTABLISHED: Kootenai County, Idaho, 1976.
REMARKS: Diagnostic horizons and features recognized in this pedon include:
Ochric epipedon the zone from 0 to 10 inches (O, A, and Bt1 horizons).
Argillic horizon the zone from 10 to 20 inches (Bt2 and Bt3 horizons) with the zone from 5 to 10 inches (Bt1 horizon) containing oriented clay, however, failing to meet the 20 percent increase in clay accumulation from the horizon above.
Vitrandic feature the zone from 2 to 10 inches
Ultic feature the zone from 10 to 30 inches having an assumed base saturation (sum) of less than 75 percent in one or more horizons.
Lithic feature the zone beginning at 32 inches
Particle-size control section the zone from10 to 20 inches
Classification revised 03/03 from loamy-skeletal, mixed, mesic Ultic Haploxeralfs to loamy-skeletal, isotic Vitrandic Haploxeralfs