LOCATION GROWDEN WA+OREstablished Series
TAXONOMIC CLASS: Loamy-skeletal, isotic Haploxerandic Humicryepts
TYPICAL PEDON: Growden ashy fine sandy loam - mountain park. (Colors are for dry soil unless otherwise noted. Textures are apparent field textures)
A1--0 to 6 inches; dark grayish brown (10YR 4/2) ashy fine sandy loam, very dark grayish brown (10YR 3/2) moist; moderate medium and coarse granular structure; soft, very friable, nonsticky, nonplastic; many fine roots; 10 percent fine gravel and gravel; strongly acid (pH 5.4); clear wavy boundary. (5 to 8 inches thick)
A2--6 to 12 inches; brown (10YR 4/3) ashy fine sandy loam, dark brown (10YR 3/3) moist; weak fine granular structure; soft, very friable, nonsticky, nonplastic; many fine roots; 10 percent fine gravel and gravel; moderately acid (pH 5.6); clear wavy boundary. (5 to 8 inches thick)
2A3--12 to 24 inches; brown (10YR 4/3) stony fine sandy loam, dark brown (10YR 3/3) moist; massive, soft, very friable, nonsticky, nonplastic; many fine roots; 10 percent fine gravel, 20 percent angular stones; moderately acid (pH 5.8); clear wavy boundary. (10 to 13 inches thick)
2AC--24 to 36 inches; brown (10YR 5/3) very stony sandy loam, dark brown (10YR 3/3) moist; single grained; loose, nonsticky, nonplastic; few fine roots; 10 percent fine gravel, 40 percent angular stones; moderately acid (pH 5.9); clear wavy boundary. (0 to 18 inches thick)
2C--36 to 60 inches; brown (10YR 5/3) stony sandy loam, dark yellowish brown (10YR 3/4) moist; single grained; loose, nonplastic; 10 percent gravel, 20 percent angular stones; moderately acid (pH 5.9).
TYPE LOCATION: Ferry County, Washington; Colville National Forest on Barnaby Buttes; northwest 1/4, southwest 1/4, section 18, T. 35 N., R. 35 E.
RANGE IN CHARACTERISTICS: The mean annual soil temperature at a depth of 20 inches ranges from 40 to 43 degrees F, and the mean summer temperature is less than 47 degrees F. The soils are usually moist but are dry in all parts between a depth of 8 and 24 inches for 45 to 60 consecutive days following the summer solstice. The umbric epipedon is more than 20 inches thick. The upper 7 to 14 inches has an estimated moist bulk density of 0.85 to 0.95 g/cc, volcanic glass content of 5 to 20 percent, acid-oxalate extractable aluminum plus one-half of the acid-oxalate extractable iron of 1.0 to 2.0 percent, and 15-bar water retention of 5 to 12 percent for air dried samples.
The A1 and A2 horizons have value of 4 or 5 dry, 2 or 3 moist, and chroma of 2 or 3 dry or moist. It is ashy fine sandy loam or ashy silt loam. It is moderately acid to strongly acid.
The 2A3 has value of 4 or 5 dry, 2 or 3 moist, and chroma of 2 or 3 dry or moist. It is stony fine sandy loam or sandy loam. It is moderately acid to strongly acid.
The 2C horizon has value of 5 or 6 dry and chroma of 2 or 3, dry or moist. It is gravelly, cobbly, stony, very gravelly or very cobbly.
COMPETING SERIES: This is the Puzzlecreek series. Puzzlecreek soils have a lithic contact at depths of 20 to 40 inches.
GEOGRAPHIC SETTING: Growden soils are on glaciated south-facing mountain slopes at elevations of 5,500 to 6,500 feet. These soils formed in mixed loess, volcanic ash, and colluvium from siliceous rock sources. They are in a cold subhumid climate with a mean annual temperature of 38 degrees F., a mean annual precipitation of 20 to 30 inches, and a frost-free period of 80 to 100 days.
GEOGRAPHICALLY ASSOCIATED SOILS: These are the Buhrig, Leonardo, Pepoon, Scar, Sitdown, and Togo soils. Buhrig soils are 20 to 40 inches deep to a lithic contact and are on mountain ridges and knobs. Leonardo soils are ashy over loamy-skeletal and are on glaciated mountain slopes. Sitdown soils are sandy-skeletal and have an ochric epipedon and are on backslopes and footslopes of mountains, outwash terraces and terrace escarpments. Pepoon soils have a lithic contact within depth of 20 inches and are on glacially abraded mountain ridges, knolls, peaks, and saddles. Scar soils are ashy over sandy or sandy-skeletal and are on mountains. Togo soils have an ochric epipedon and are on backslopes, footslopes, and ridges of mountains.
DRAINAGE AND PERMEABILITY: Well drained; medium runoff; moderately rapid permeability.
USE AND VEGETATION: Grazing and timber production. Vegetation is subalpine fir, Douglas-fir, and lodgepole pine with an understory of Utah honeysuckle, sticky currant, pachystima, silky lupine, heartleaf arnica and Indian paintbrush.
DISTRIBUTION AND EXTENT: Northeastern Washington. MLRA 43A. Series is of moderate extent.
MLRA SOIL SURVEY REGIONAL OFFICE (MO) RESPONSIBLE: Bozeman, Montana
SERIES ESTABLISHED: Ferry County, Washington, 1971.
REMARKS: Diagnostic horizon and features recognized in this pedon are an umbric epipedon from the mineral surface to 24 inches. Rock fragments in the 10 to 40 inch particle-size control section average 37 percent.
9/2005- This soil has been reclassified to Dystrocryepts based on Keys to Taxonomy, 8th edition.
6/2007- This soil has been reclassified from Loamy-skeletal, mixed, superactive Andic Dystrocryepts to Loamy-skeletal, isotic Haploxerandic Humicryepts based on the 10th edition Keys to Soil Taxonomy.