LOCATION HARWOOD WAEstablished Series
TAXONOMIC CLASS: Fine-loamy, mixed, superactive, mesic Haploduridic Durixerolls
TYPICAL PEDON: Harwood loam, rangeland. (Colors are for dry soil unless otherwise stated.)
A1--0 to 4 inches; grayish brown (10YR 5/2) loam, very dark grayish brown (10YR 3/2) moist; moderate thin platy structure parting; slightly hard, friable, slightly sticky and slightly plastic; many roots; neutral (pH 7.0); abrupt wavy boundary. (3 to 5 inches thick)
A2--4 to 8 inches; grayish brown (10YR 5/2) loam, very dark grayish brown (10YR 3/2) moist; moderate medium platy structure parting to thin platy; hard, friable, slightly sticky and slightly plastic; common roots; few fine tubular pores; slightly alkaline (pH 7.0); clear wavy boundary. (3 to 5 inches thick)
Bw1--8 to 18 inches; brown (7.5YR 5/3) loam, dark brown (10YR 3/3) moist; weak medium prismatic structure; slightly hard, friable, slightly sticky and slightly plastic; common roots; common fine tubular pores; about 1 percent pebbles; slightly alkaline (pH 7.8); clear wavy boundary. (9 to 12 inches thick)
Bw2--18 to 24 inches; brown (7.5YR 5/4) loam, dark brown (7.5YR 3/4) moist; moderate medium prismatic structure; hard, firm, slightly sticky and moderately plastic; common roots; common fine tubular pores; about 1 percent rock fragments; slightly alkaline (pH 7.8); clear wavy boundary. (5 to 10 inches thick)
Bw3--24 to 26 inches; brown (7.5YR 5/4) loam, dark brown (7.5YR 3/4) moist; moderate medium angular blocky structure; very hard, very firm, slightly sticky and moderately plastic; common roots; many fine tubular pores; about 1 percent coarse fragments; moderately alkaline (pH 8.0); abrupt wavy boundary. (0 to 4 inches thick)
Bq--26 to 30 inches; brown (7.5YR 5/4) gravelly loam, dark brown (7.5YR 3/4) moist; massive; very hard, very firm, moderately sticky and moderately plastic; few roots; many fine tubular pores; 25 percent pebbles and 5 percent cobbles; silica coatings on pebbles; moderately alkaline (pH 8.0); abrupt smooth boundary. (0 to 5 inches thick)
2Bqm--30 to 60 inches; indurated silica-cemented gravel.
TYPE LOCATION: Yakima County, Washington; 1,840 feet east and 150 feet south of the southwest corner of section 31, T.13N., R.17E., W.M.
RANGE IN CHARACTERISTICS: Depth to the duripan ranges from 20 to 40 inches. Mean annual soil temperature ranges from 48 degrees to 54 degrees F. These soils are dry between depths of 8 and 12 inches more than 1/2 the time when the soil temperature is above 40 degrees F. The mollic epipedon ranges from 7 to 15 inches thick. The control section contains 18 to 25 percent clay, more than 15 percent fine sand or coarser, and less than 15 percent rock fragments by weighted average.
The A horizon has value of 4 or 5 dry, 2 or 3 moist or dry. It is loam, silt loam, or very stony silt loam, and has weak or moderate structure.
The Bw horizon has hue of 10YR or 7.5YR, value of 5 or 6 dry, 3 or 4 moist, and chroma of 3 or 4 dry or moist. It is loam or silt loam and has moderate blocky or prismatic structure.
The Bq horizon has hue of 10YR or 7.5YR, and chroma of 3 or 4 moist or dry. It is gravelly loam, silt loam, or gravelly silt loam, and is massive or has weak blocky structure.
COMPETING SERIES: This is the Maupin series. Maupin soils have secondary lime in and above the duripan.
GEOGRAPHIC SETTING: Harwood soils are on uplands and high dissected terraces. Slopes are 0 to 60 percent. The soils formed in loess and in old alluvium. Elevations are 1,200 to 2,000 feet. The soils are in a semiarid climate with hot, dry summers and cool, most winters. The mean annual precipitation ranges from 8 to 12 inches. Mean annual temperature is 49 degrees to 54 degrees F.; and the frost-free season is 135 to 150 days.
GEOGRAPHICALLY ASSOCIATED SOILS: These are the Cowiche, Gorst, Selah, and Simcoe soils. Cowiche and Simcoe soils lack a duripan. Gorst soils are less than 20 inches deep to the duripan. Selah soils have an argillic horizon and the duripan has lime-silica cementation.
DRAINAGE AND PERMEABILITY: Well drained; slow or medium runoff; moderate permeability above the duripan and very slow within the duripan.
USE AND VEGETATION: Used for range and irrigated orchard, hay, and pasture. Native vegetation is bunchgrasses and big sagebrush.
DISTRIBUTION AND EXTENT: South-central Washington. Series is of moderate extent.
MLRA SOIL SURVEY REGIONAL OFFICE (MO) RESPONSIBLE: Portland, Oregon
SERIES ESTABLISHED: Yakima County, Washington, 1947.
REMARKS: Diagnostic horizons and other features recognized in this pedon:
Mollic epipedon - the zone from 0 to 8 inches (A horizon)
Cambic horizon - the zone from 8 to 30 inches (Bw and Bq horizons)
Duripan - the zone 30 to 60 inches (Bqm horizon)