LOCATION BLACKPRINCE             ID+WA

Established Series
Rev. CJW/RL/RJS
06/2016

BLACKPRINCE SERIES

The Blackprince series consists of moderately deep, well drained soils on mountains, foothills and canyon sides. They formed in material weathered from gneiss and granitic bedrock with minor amounts of loess and volcanic ash in the upper part. Permeability is moderately rapid. Slope ranges from 15 to 75 percent. The average annual air temperature is about 44 degrees F and the average annual precipitation is about 34 inches.

TAXONOMIC CLASS: Loamy-skeletal, isotic, frigid Vitrandic Haploxerepts

TYPICAL PEDON: Blackprince gravelly ashy sandy loam, forest; on a southeast-facing convex slope of 38 percent at 3,040 feet elevation. When described on June 16, 1982, the soil was slightly moist throughout. (Colors are for dry soil unless otherwise stated.)

Oi--0 to 0.5 inch; slightly decomposed needles, leaves, and twigs.

Oe--0.5 to 1 inch; decomposed organic matter mixed with 1980 Mt. St. Helens volcanic ash.

A--1 to 4 inches; brown (10YR 5/3) gravelly ashy sandy loam, dark brown (10YR 3/3) moist; weak fine subangular blocky structure parting to weak fine granular; slightly hard, friable, nonsticky and slightly plastic; many very fine, fine, and common medium roots; many very fine and fine interstitial and common fine tubular pores; 20 percent gravel; neutral (pH 6.7); clear wavy boundary. (2 to 5 inches thick)

BA--4 to 12 inches; pale brown (10YR 6/3) gravelly ashy sandy loam, brown (10YR 4/3) moist; weak fine and medium subangular blocky structure; slightly hard, friable, slightly sticky and slightly plastic; common very fine, fine and few medium and coarse roots; many very fine and fine tubular and interstitial pores; 20 percent gravel; slightly acid (pH 6.5); gradual wavy boundary. (7 to 10 inches thick)

Bt--12 to 23 inches; very pale brown (10YR 7/4) very gravelly coarse sandy loam, yellowish brown (10YR 5/4) moist; weak medium and coarse subangular blocky structure; slightly hard, friable, slightly sticky and slightly plastic; common very fine, fine and few medium roots; many very fine and fine interstitial and few fine tubular pores; few faint clay films on faces of peds and common faint clay films lining pores; 35 percent gravel; moderately acid (pH 5.6); abrupt wavy boundary. (6 to 13 inches thick)

C--23 to 29 inches; variegated extremely gravelly loamy coarse sand; massive; slightly hard, friable, nonsticky and nonplastic; few very fine roots; many fine and medium interstitial pores; 60 percent gravel; strongly acid (pH 5.3); abrupt wavy boundary. (5 to 12 inches thick)

Cr--29 inches; soft weathered granitic bedrock.

TYPE LOCATION: Shoshone County, Idaho; about 0.5 mile north of the community of Marble Creek, about 1,900 feet north and 700 feet east of the southwest corner of sec. 12, T. 45 N., R. 3 E. Latitude - 47 degrees, 15 minutes, 29.82 seconds North; Longitude - 116 degrees, 1 minute, 44.63 seconds West; NAD83; USGS quadrangle, Marble Creek, ID.

RANGE IN CHARACTERISTICS:

Depth to soft bedrock - 20 to 40 inches
Soil moisture - dry mid July to mid September (45 to 60 days), moist mid September through June
Average annual soil temperature - 43 to 46 degrees F
Average summer soil temperature - 48 to 56 degrees F with an O horizon
Volcanic ash influence - 9 to 20 inches thick
Estimated properties of ash influenced layer:
Volcanic glass content - 5 to 25 percent
Acid oxalate Al + 1/2Fe - 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
Hue - 10YR or 7.5YR
Value - 5 or 6 dry, 3 or 4 moist
Chroma - 2 or 3, dry or moist
Texture - ashy sandy loam or ashy coarse sandy loam
Value - 5 or 6 dry, 3 or 4 moist
Gravel content - 15 to 25 percent
Clay content - 6 to 12 percent
Reaction - slightly acid or neutral

Bw horizon (present in some pedons)
Hue - 10YR or 7.5YR
Value - 5 to 7 dry and 3 to 5 moist
Chroma - 3 or 4 dry or moist
Texture - ashy sandy loam or ashy coarse sandy loam
Gravel content - 35 to 45 percent
Cobble content - 0 to 5 percent
Clay content - 6 to 12 percent
Reaction - strongly acid to slightly acid

Bt horizon
Hue - 10YR or 7.5YR
Value - 6 or 7 dry, 4 or 5 moist
Chroma - 3 or 4, dry or moist
Texture - sandy loam or coarse sandy loam
Gravel content - 35 to 55 percent
Cobble content - 0 to 5 percent
Clay content - 6 to 12 percent
Reaction - moderately acid to neutral

C horizon
Hue - 10YR, 7.5YR or variegated
Value - 7 or 8 dry and 5 or 6 moist
Chroma - 2 to 4, dry or moist
Texture - loamy sand or loamy coarse sand
Gravel content - 40 to 60 percent
Cobble content - 0 to 10 percent
Reaction - strongly acid to slightly acid

BC horizons present in some pedons
Hue - 2.5Y or 10YR
Value - 5 or 6 moist
Chroma - 3 or 4 dry or moist
Texture - sandy loam, coarse sandy loam or loamy coarse sand
Gravel content - 40 to 60 percent
Cobble content - 0 to 10 percent
Total rock fragment content - 40 to 60 percent
Reaction - moderately acid or slightly acid

COMPETING SERIES: These are the Analulu, Ardenvoir, Ardtoo, Blinn, Brevco, Coxit, Daxty, Easte, Highhorn, Huntrock, Jimbluff, Jumpe, Kamela, Lekrem, Lemoncreek, Longort, Minaloosa, Noil, Ontrail, Radercreek, Redpeak, Santop, Seeburg, Thout, Threecabin and Warfield series. Analulu, Blinn Brevco, Daxty, Huntrock, Kamela, Lemoncreek, Redpeak, Santop and Thout soils are all moderately deep to a lithic contact. Ardenvoir, Ardtoo, Easte, and Noil soils are deep to a paralithic contact. Coxit, Jimbluff, Jumpe, Lekrem, Minaloosa, Ontrail, and Seeburg soils are very deep. Highhorn, Radercreek, Threecabin,and Warfield soils are deep to a lithic contact. Longort soils are moderately deep to densic material.

GEOGRAPHIC SETTING: Blackprince soils are on south, east and west-facing foothills and canyon sides. Slopes range from 15 to 75 percent. These soils formed in material weathered from gneiss or granitic bedrock with minor amounts of loess and volcanic ash in the upper part. Elevations range from 2,000 to 4,150 feet. The average annual air temperature ranges from 42 to 46 degrees F, and average annual precipitation of 25 to 38 inches. The average frost-free period is from 90 to 120 days.

GEOGRAPHICALLY ASSOCIATED SOILS: These are the Jacot, Kruse, and Lotuspoint soils. Jacot soils are on dissected foothills on north aspects, have a thick volcanic ash mantle, and are more than 60 inches deep. Kruse soils are on west or east aspects of dissected foothills and have fine-loamy argillic horizons. Lotuspoint soils are on ridges and south aspects, have a lithic contact at 20 to 40 inches and are mesic.

DRAINAGE AND PERMEABILITY: Well drained; rapid to very rapid runoff; moderately rapid permeability in the solum and rapid permeability in the substratum.

USE AND VEGETATION: These soils are used for timber production, livestock grazing, recreation, wildlife habitat and watershed. A few areas are used for homesites. Potential natural vegetation is mainly grand fir, Douglas-fir, ponderosa pine, and western larch, with an understory of Columbia brome, pinereedgrass, bluebunch wheatgrass, northern bedstraw, mallow ninebark, creambush oceanspray, low Oregon grape, common snowberry, white spirea, rose, Oregon fairybells, and starry false-Solomons-seal.

DISTRIBUTION AND EXTENT: Northern Idaho and northeastern Washington; MLRA 43A. This soil is of moderate extent.

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

SERIES ESTABLISHED: St. Joe Area, Shoshone County, Idaho, 1993.

REMARKS: Diagnostic horizons and features recognized in the pedon are:
Ochric epipedon - the zone from 0 to 4 inches (Oi, Oe and A horizons)
Cambic horizon - the zone from 4 to 23 inches (BA and Bt horizons)
Paralithic contact - the boundary at 29 inches (Cr horizon)
Particle-size control section - the zone from 11 to 29 inches (part of the BA, and the Bt and C horizons)
Vitrandic feature - the zone from 1 to 12 inches (A and BA horizons) having estimated properties of 5 to 20 percent volcanic glass, 0.4 to 1.0 percent acid-oxalate extractable aluminum plus 1/2 iron, moist bulk density of 1.0 to 1.2 g/cc, and 15-bar moisture of 5 to 10 percent.

Classification revised 11/01 from Dystric Xerochrepts to Vitrandic Dystroxerepts based on revisions to Soil Taxonomy. Classification revised 9/2009 from Loamy-skeletal, isotic, frigid Vitrandic Dystroxerepts to Loamy-skeletal, isotic, frigid Vitrandic Haploxerepts based on a review of lab data in similar soils.

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National Cooperative Soil Survey
U.S.A.