LOCATION CUBHILL WAEstablished Series
TAXONOMIC CLASS: Loamy-skeletal, mixed, superactive, mesic Vitrandic Argixerolls
TYPICAL PEDON: Cubhill gravelly ashy loam - rangeland, on a south facing 34 percent slope at an elevation of 3,300 feet. (Colors are for dry soil unless otherwise stated. All textures are apparent field textures.)
A1--0 to 9 inches; dark grayish brown (10YR 4/2) gravelly ashy loam, very dark grayish brown (10YR 3/2) moist; weak fine and medium subangular blocky breaking to weak fine granular structure; soft, very friable, nonsticky and nonplastic; many very fine and fine and few medium and coarse roots; common medium irregular pores; 20 percent pebbles; neutral (pH 7.0); gradual wavy boundary.
A2--9 to 18 inches; dark grayish brown (10YR 4/2) gravelly ashy loam, very dark grayish brown (10YR 3/2) moist; weak fine and medium subangular blocky structure; soft, very friable, nonsticky and nonplastic; many very fine and fine and few medium roots; common medium irregular pores; 20 percent pebbles and 3 percent cobbles; neutral (pH 7.0); clear wavy boundary. (combined thickness of the A horizons is 12 to 18 inches)
2AB--18 to 25 inches; grayish brown (10YR 5/2) very gravelly loam; very dark grayish brown (10YR 3/2) moist; moderate medium and fine subangular blocky structure; soft, very friable, nonsticky and nonplastic; common very fine and fine and few medium roots; common fine irregular pores; 25 percent pebbles and 10 percent cobbles; neutral (pH 7.2); clear wavy boundary. (5 to 8 inches thick)
2Bt1--25 to 36 inches; brown (10YR 5/3) very gravelly clay loam, brown (10YR 4/3) moist; moderate medium subangular blocky structure; hard, friable, slightly sticky and slightly plastic; few very fine and fine roots; few fine irregular pores; few discontinuous faint clay films on faces of peds and in pores; 30 percent pebbles and 10 percent cobbles; neutral (pH 7.0); clear wavy boundary.
2Bt2--36 to 60 inches; pale brown (10YR 6/3) very gravelly clay loam, brown (10YR 5/3) moist; massive; very hard, friable, moderately sticky and slightly plastic; few very fine roots; few fine irregular pores; few discontinuous faint clay films on faces of peds and in pores; 35 percent pebbles and 10 percent cobbles; neutral (pH 7.0). (Combined thickness of the 2Bt horizons is 30 to 45 inches.)
TYPE LOCATION: Okanogan County, Washington; about 6.5 miles north of Winthrop, Washington; 980 feet east and 2,650 feet south of the northwest corner of section 29, T. 36 N., R. 21 E. (Latitude 48 degrees 35 minutes 30 seconds N., Longitude 120 degrees 14 minutes 44 seconds W)
RANGE IN CHARACTERISTICS: The mean annual soil temperature at a depth of 20 inches ranges from 47 to 53 degrees F. These soils are usually moist but are dry in all parts of the moisture control section 90 to 105 consecutive days following the summer solstice. The mollic epipedon is 15 to 25 inches thick. The upper 12 to 18 inches of the soil has an estimated moist bulk density of 1.10 to 1.40 g/cc, volcanic glass content of 5 to 20 percent, acid-oxalate extractable aluminum plus one-half of the acid-oxalate extractable iron of 0.4 to 1.0 percent, and 15-bar water retention of 5 to 10 percent for air dried samples. The particle-size control section averages 35 to 50 percent rock fragments and 20 to 34 percent clay.
The A horizon has values of 3 or 4 dry, 2 or 3 moist, and chroma of 2 or 3 dry or moist.
The 2AB horizon has values of 4 or 5 dry, 3 or 4 moist, and chroma of 2 or 3 dry or moist. It is very gravelly loam or gravelly loam. It has 20 to 30 percent pebbles and 5 to 10 percent cobbles.
The 2Bt horizon has values of 5 or 6 dry, 4 or 5 moist, and chroma of 3 to 4 dry or moist. It is very gravelly clay loam, very gravelly loam or very gravelly sandy clay loam. It has 30 to 40 percent pebbles and 5 to 10 percent cobbles. Reaction ranges from slightly acid to neutral.
COMPETING SERIES: These are the Blint, Brysill(T), Bunselmeier, Hehe, Lainand, Leidl, McDaniel, Nint(T), Norod, Setill and Skooker series. Brysill soils have an argillic horizon that extends to a depth of less than 40 inches and have acid oxalate extractable aluminum plus one-half iron of less than 0.4 percent. Bunselmeier soils are 40 to 60 inches deep to cinders. Blint, Leidl, Nint, and Norod soils are 20 to 40 inches to a lithic contact. Hehe soils are 20 to 40 inches deep to a paralithic contact. Lainand soils are 40 to 60 inches deep to a lithic contact. McDaniel soils are dry for 75 to 95 consecutive days. Setill soils are dry for 70 to 90 days. Skooker soils are 40 to 60 inches to a paralithic contact and are dry for 60 to 90 consecutive days.
GEOGRAPHIC SETTING: Cubhill soils are on back slopes and foot slopes of foothills. These soils formed in glacial till from sedimentary and volcanic rock with a component of volcanic ash in the upper part. Slopes range from 15 to 35 percent. Elevation ranges from 2,900 to 4,500 feet. Climate is characterized by hot, dry summers and mild, moist winters. The average annual precipitation is 15 to 18 inches. The average January temperature ranges from 24 to 28 degrees F. The average July temperature ranges from 68 to 72 degrees F. The average annual temperature is 47 to 52 F. and the frost free season ranges from 110 to 140 days.
GEOGRAPHICALLY ASSOCIATED SOILS: These are the Johntom and Sycreek soils. Johntom soils are on shoulders and ridges and are 10 to 20 inches to lithic contact. Sycreek soils are on gently sloping to steep drainage sideslopes and footslopes that are forested and have a frigid soil temperature regime.
DRAINAGE AND PERMEABILITY: Well drained, rapid runoff; moderately slow permeability.
USE AND VEGETATION: Rangeland, grazing and wildlife habitat. Native vegetation is Wyoming big sagebrush, antelope bitterbrush, bluebunch wheatgrass, Idaho fescue, common yarrow, arrowleaf balsamroot, eriogonum and scattered ponderosa pine.
DISTRIBUTION AND EXTENT: Northcentral Washington. The series is of small extent.
MLRA SOIL SURVEY REGIONAL OFFICE (MO) RESPONSIBLE: Portland, Oregon
SERIES ESTABLISHED: Okanogan National Forest, Okanogan County, Washington, 2005.
REMARKS: Diagnostic horizons and features in this pedon are:
Mollic epipedon - 0 to 25 inches (A1, A2 and 2AB horizons)
Argillic horizon - 25 to 60 inches (Bt1 and Bt2 horizons)
PSCS - zone from 25 to 45 inches (Bt1 and part of Bt2 horizon)
Vitrandic feature - 0 to 18 inches (A1 and A2 horizons)