LOCATION DARLAND WAEstablished Series
TAXONOMIC CLASS: Loamy-skeletal, isotic Vitrandic Haplocryolls
TYPICAL PEDON: Darland stony ashy loam - rangeland. (Colors are for dry soil unless otherwise stated.)
A1--0 to 8 inches; dark yellowish brown (10YR 4/4) stony ashy loam, very dark grayish brown (10YR 3/2) moist; moderate medium granular structure; slightly hard, friable, slightly sticky and slightly plastic; many fine roots; few fine pores; 30 percent gravel, 1 percent cobbles and less than 1 percent stones; neutral (pH 6.6); abrupt smooth boundary. (7 to 19 inches thick)
A2--8 to 14 inches; brown (10YR 4/3) very gravelly loam, very dark grayish brown (10YR 3/2) moist; moderate fine and medium granular structure; soft, friable, slightly sticky and slightly plastic; common fine and medium roots; few fine pores; 35 percent gravel and 5 percent cobbles; neutral (pH 6.6); clear wavy boundary. (0 to 6 inches thick)
A3--14 to 31 inches; brown (10YR 4/3) very cobbly loam; very dark grayish brown (10YR 3/2) moist; weak fine granular structure; soft, very friable, slightly sticky and slightly plastic; many fine roots; 35 percent gravel and 25 percent cobbles; slightly acid (pH 6.4); clear wavy boundary. (13 to 18 inches thick)
Bw--31 to 43 inches; dark yellowish brown (10YR 4/4) extremely cobbly loam, brown (10YR 4/3) moist; weak fine granular structure; soft, very friable, slightly sticky and slightly plastic; many fine roots; 15 percent gravel and 65 percent cobbles; slightly acid (pH 6.4); gradual wavy boundary. (10 to 13 inches thick)
C--43 to 60 inches; dark yellowish brown (10YR 4/4) extremely cobbly sandy loam, dark brown (10YR 3/3) moist; single grain; loose, nonsticky and nonplastic; few fine and medium roots; 10 percent gravel, 70 percent cobbles and 10 percent stones; slightly acid (pH 6.4).
TYPE LOCATION: Yakima County, Washington; approximately 6 miles west of the Ahtanum Guard Station; 2,900 feet west and 2,550 feet north of the southeast corner of section 23, T. 12 N., R. 13 E.
RANGE IN CHARACTERISTICS: The mollic epipedon is 20 to 43 inches thick. The mean annual soil temperature is 43 degrees to 45 degrees F. The upper 7 to 19 inches is assumed to be 5 to 20 percent volcanic glass, 0.4 to 1.0 percent acid oxalate extractable aluminum plus one-half iron and moist bulk density of 1.10 to 1.30 g/cc. The particle-size control section has 10 to 18 percent clay and has 35 to 80 percent basalt fragments. Solum thickness and depth to bedrock is 40 to more than 60 inches.
The A1 horizon has value of 4 or 5 dry, 2 or 3 moist and chroma of 3 or 4 dry, 2 or 3 moist. Texture is stony ashy loam, very gravelly ashy loam, or very gravelly ashy fine sandy loam. Reaction is moderately acid to neutral.
The A2 (when present) and A3 horizons have color similar to the A1 horizon. Texture is very gravelly loam, very cobbly loam or extremely cobbly loam. Reaction is moderately acid to neutral.
The Bw horizon has value of 4 or 5 dry, 3 or 4 moist and chroma of 3 or 4 moist. Texture is very gravelly, very cobbly or extremely cobbly loam. Reaction is moderately acid to neutral.
The C horizon, when present, has value of 4 or 5 dry and chroma of 3 or 4 moist. Texture is very cobbly sandy loam, extremely cobbly sandy loam, extremely cobbly loam, or extremely gravelly loam. Reaction is moderately acid or slightly acid.
COMPETING SERIES: This is the Brickel series. Soils with similar Haplocryolls or Cryoborolls classification with mixed mineralogy are the Chocktoot, Edgway, Lagall and Lowland series. Brickel soils are 20 to 40 inches deep to a lithic contact. Edgway soils have a mollic epipedon 10 to 14 inches thick and a udic soil moisture regime. Lagall soils have a mollic epipedon 10 to 15 inches thick and a udic soil moisture regime. Lowland soils have a mollic epipedon 8 to 16 inches thick and an average annual soil temperature of 38 to 42 degrees F.
GEOGRAPHIC SETTING: Darland soils are on southerly exposed convex mountain side slopes. Slopes range from 5 to 75 percent. Elevation ranges from 5,000 to 6,900 feet. The soils formed in colluvium of Yakima basalt mixed with loess and minor amounts of volcanic ash. The basalt is angular with a yellowish brown (10YR 5/4) weathering rind and cannot be broken in the hand. Some fragments are scoriaceous. These soils are in a climate with warm dry summers and cool moist winters. The mean annual precipitation is 25 to 70 inches. The average January temperature is about 22 degrees F. and the average July temperature is 62 degrees F. The mean annual temperature is 41 to 43 degrees F. The frost-free season is less than 90 days.
GEOGRAPHICALLY ASSOCIATED SOILS: These are the Naxing soils. Naxing soils lack a mollic epipedon.
DRAINAGE AND PERMEABILITY: Well drained; moderately rapid permeability.
USE AND VEGETATION: This soil is used for recreation and wildlife habitat. Vegetation is sagebrush, scarlet gilia, elk sedge, mountain parsley, balsamroot, and pachystima.
DISTRIBUTION AND EXTENT: Mountains of western Yakima County. This series is of small extent.
MLRA OFFICE RESPONSIBLE: Portland, Oregon
SERIES ESTABLISHED: Yakima County, Washington, 1979.
REMARKS: Diagnostic horizons and features recognized in this pedon:
Mollic epipedon - 0 to 31 inches (A1, A2, and A3 horizons)
Cambic horizon - 31 to 43 inches (Bw horizon)
Vitrandic feature - 0 to 8 inches (assumed)
Pachic feature - 0 to 31 inches
Particle-size control section - 10 to 40 inches
Xeric soil moisture regime.