LOCATION BREVCO WA
Established Series
Rev. EMM/RWL/SHB/SBC
06/2016
BREVCO SERIES
Landscape--mountains
Landform--hillslopes, mountain slopes
Slope--3 to 65 percent
Parent material--residuum and colluvium derived from granitic rock with a minor amount of volcanic ash in upper part
Mean annual precipitation--about 560 cm
Mean annual air temperature--about 6 degrees C
Depth class--moderately deep
Drainage class--well drained
Soil moisture regime--xeric
Soil temperature regime--frigid
Soil moisture subclass--typic
TAXONOMIC CLASS: Loamy-skeletal, isotic, frigid Vitrandic Haploxerepts
TYPICAL PEDON: Brevco gravelly ashy coarse sandy loam, under a canopy of Douglas-fir and lodgepole pine, on a 40-percent, northeast-facing slope at an elevation of 1300 m (When described on July 27, 1992, the soil was dry throughout. All textures are apparent field textures.)
Oi--0 to 3 cm; slightly decomposed organic matter consisting of needles and grasses
A--3 to 10 cm; gravelly ashy coarse sandy loam, very pale brown (10YR 7/3) dry, brown (10YR 4/3) moist; weak fine granular structure; soft, very friable, nonsticky and nonplastic; many fine and very fine and common medium and coarse roots; common fine irregular pores; 20 percent gravel; neutral (pH 6.6); clear smooth boundary
Bw--10 to 30 cm; gravelly ashy coarse sandy loam, very pale brown (10YR 7/4) dry, dark yellowish brown (10YR 4/4) moist; weak fine and medium subangular blocky structure; soft, very friable, nonsticky and nonplastic; many fine and very fine and common medium and coarse roots; common fine irregular pores; 25 percent gravel; slightly acid (pH 6.2); clear wavy boundary
C1--30 to 66 cm; very gravelly sandy loam, very pale brown (10YR 8/3) dry, brown (10YR 5/3) moist; massive; soft, very friable, nonsticky and nonplastic; many fine and common medium and coarse roots; 30 percent gravel and 15 percent cobbles; moderately acid (pH 5.8); gradual wavy boundary
C2--66 to 99 cm; very cobbly coarse sandy loam, very pale brown (10YR 7/4) dry, light yellowish brown (10YR 6/4) moist; massive; soft, very friable, nonsticky and nonplastic; common fine and medium roots; 25 percent gravel and 30 percent cobbles; moderately acid (pH 5.6); abrupt irregular boundary
R--99 cm; fractured granite
TYPE LOCATION: Okanogan County, Washington; about 2 km northwest of Ramsey Peak; Lewis Butte U.S. Geological Survey topographic quadrangle; about 640 m west and 110 m south of the northeast corner of section 6, T. 36 N, R. 22 E; latitude 48.567918, longitude -120.128146, datum WGS 84 (coordinates estimated from PLSS details)
RANGE IN CHARACTERISTICS:
Mean annual soil temperature--4 to 7 degrees C
Moisture control section--usually moist, but dry in all parts 60 to 75 consecutive days following summer solstice
Depth to lithic contact--50 to 100 cm from surface of mineral soil
Content of rock fragments in particle-size control section--averages 35 to 60 percent
Solum
*Thickness--25 to 36 cm
*Estimated moist bulk density--1.00 to 1.55 g/cm3
*Estimated content of volcanic glass--5 to 20 percent
*Estimated acid oxalate Al plus 1/2 Fe--0.2 to 0.6 percent
*Estimated 15-bar water retention--5 to 10 percent (air-dried samples)
A horizon
*Value--5 to 7 dry, 2 to 5 moist
*Chroma--2 or 3 dry or moist
*Texture--gravelly ashy coarse sandy loam, gravelly ashy sandy loam, ashy sandy loam
*Content of gravel--15 to 30 percent
*Reaction--6.1 to 7.3
*Thickness--5 to 13 cm
An AB horizon is in some pedons.
Bw horizon
*Value--6 or 7 dry, 3 to 5 moist
*Chroma--2 to 4 dry or moist
*Texture--gravelly ashy coarse sandy loam, very gravelly ashy coarse sandy loam, gravelly ashy sandy loam, very gravelly ashy sandy loam
*Content of gravel--15 to 45 percent
*Content of cobbles--0 to 10 percent
*Total content of rock fragments--15 to 55 percent
*Reaction--5.6 to 7.3
*Thickness--15 to 28 cm
C horizon
*Hue--10YR, 2.5Y
*Value--6 to 8 dry, 4 to 6 moist
*Chroma--2 to 4 dry or moist
*Texture--very gravelly sandy loam, very gravelly coarse sandy loam, very cobbly coarse sandy loam, extremely gravelly coarse sandy loam, extremely gravelly loamy coarse sand
*Content of rock fragments--averages 35 to 75 percent
*Content of gravel--25 to 60 percent
*Content of cobbles--5 to 25 percent
*Reaction--5.6 to 7.3
*Combined thickness--25 to 75 cm
A BC horizon is present in some pedons.
COMPETING SERIES:
Analulu--dry 45 to 60 consecutive days; argillite or other metasedimentary rock fragments
Ardenvoir--loam C horizon; paralithic contact of metasedimentary rock
Ardtoo--deep to paralithic contact
Blackprince--moderately deep to paralithic contact
Blinn--dry 45 to 60 consecutive days; basalt rock fragments
Coxit,
Jimbluff,
Jumpe,
Lekrem,
Minaloosa,
Ontrail,
Seeburg--very deep
Daxty--volcanic tuff flat channers and flagstones
Easte--umbric epipedon; dry more than 90 consecutive days
Highhorn--2Bwb horizon, silty clay loam subsoil; 27 to 35 percent clay in particle-size control section
Huntrock--averages 27 to 35 percent clay; 60 to 80 percent rock fragments in particle-size control section
Kamela--18 to 27 percent clay in particle-size control section; basalt rock fragments
Lemoncreek--dry 45 to 60 consecutive days; 18 to 25 percent clay in particle-size control section
Longort--moderately deep to densic material
Noil--deep to lithic contact; metasedimentary rock fragments
Radercreek--deep to lithic contact; sedimentary and volcanic rock fragments
Redpeak--hue of 2.5YR or 5YR
Santop--sandstone rock fragments; less coarse sand in C horizon
Thout--andesite or other extrusive igneous rock fragments; less coarse sand in cambic horizon
Threecabin,
Warfield--deep to lithic contact
GEOGRAPHIC SETTING:
Elevation--610 to 1675 m
Climate--warm, dry summers; cool, moist winters
Mean annual precipitation--460 to 980 mm
Mean January air temperature--about -6 to -3 degrees C
Mean July air temperature--17 to 19 degrees C
Mean annual air temperature--4 to 7 degrees C
Frost-free season--85 to 120 days
GEOGRAPHICALLY ASSOCIATED SOILS:
Goddard--on shoulders and backslopes of mountains; sandy-skeletal
Bromas--on shoulders and backslopes of mountains; cryic soil temperature regime; sandy-skeletal
Sitdown--on backslopes of mountains; cryic soil temperature regime; sandy-skeletal
Wapal--on south-facing backslopes of mountains; more than 100 cm deep to bedrock
DRAINAGE AND PERMEABILITY:
Drainage class--well drained
Saturated hydraulic conductivity (Ksat)--high
USE AND VEGETATION:
Use--timber production, wildlife habitat, watershed, recreation
Potential natural vegetation--Douglas-fir, ponderosa pine, lodgepole pine, dwarf huckleberry, mallow ninebark, common snowberry, kinnikinnick
DISTRIBUTION AND EXTENT: North-central and northeastern, Washington; MLRAs 6 and 43A; moderate extent
MLRA SOIL SURVEY REGIONAL OFFICE (MO) RESPONSIBLE: Portland, Oregon
SERIES ESTABLISHED: Okanogan National Forest, Okanogan County, Washington; 2005
REMARKS:
Diagnostic horizons and other features in this pedon
*Ochric epipedon
*Cambic horizon--zone from 10 to 30 cm
*Vitrandic feature--zone from 3 to 30 cm
*Depth to lithic contact--99 cm
*Particle-size control section--zone from 28 to 99 cm
06/2016-This official series description was updated as part of the final correlation of the Spokane County, Washington, soil survey. The type location needs to be further investigated and updated. The coordinates do not put the point in a Brevco map unit. The formatting was updated according to SSR1 Technical Note 11--Content and Format of Official Series Descriptions (revised 12/2015).
National Cooperative Soil Survey
U.S.A.