LOCATION ATHENA OR+ID WAEstablished Series
TAXONOMIC CLASS: Fine-silty, mixed, superactive, mesic Pachic Haploxerolls
TYPICAL PEDON: Athena silt loam-cultivated. (Colors are for moist soil unless otherwise noted.)
Ap--0 to 8 inches; very dark brown (10YR 2/2) silt loam, dark grayish brown (10YR 4/2) dry; moderate fine granular structure; hard, friable, slightly sticky and slightly plastic; many very fine roots; many fine and very fine irregular pores; lower 1/4 inches a firm, platy and dense plow pan; slightly acid (pH 6.4); abrupt smooth boundary. (6 to 9 inches thick)
A1--8 to 15 inches; very dark brown (10YR 2/2) silt loam, dark grayish brown (10YR 4/2) dry; weak very fine subangular blocky structure; hard, friable, slightly sticky and slightly plastic; many very fine roots; many very fine pores; neutral (pH 6.7) clear wavy boundary. (5 to 9 inches thick)
A2--15 to 26 inches; very dark grayish brown (10YR 3/2) silt loam, dark grayish brown (10YR 4/2) dry; weak coarse prismatic structure parting to fine subangular blocky; hard, friable, slightly sticky and slightly plastic; many very fine roots; many very fine pores neutral (pH 6.9); gradual wavy boundary. (0 to 12 inches thick)
Bw1--26 to 39 inches; dark brown (10YR 3/3) silt loam, brown (10YR 5/3) dry; weak coarse prismatic structure parting to moderate fine and medium subangular blocky; hard, friable, slightly sticky and slightly plastic; common very fine roots; many very fine pores; neutral (pH 7.2); clear wavy boundary. (10 to 20 inches thick)
Bw2--39 to 46 inches; dark yellowish brown (10YR 4/4) silt loam, light yellowish brown (10YR 6/4) dry; weak medium and coarse subangular blocky structure; hard, firm, slightly sticky and slightly plastic; common very fine roots; many very fine and fine pores; mildly alkaline (pH 7.5); abrupt wavy boundary. (6 to 20 inches thick)
Bk1--46 to 53 inches; dark yellowish brown (10YR 4/4) silt loam, light yellowish brown (10YR 6/4) dry; weak medium and coarse subangular blocky structure; slightly hard, firm, slightly sticky and slightly plastic; few very fine roots; many very fine pores; few dark gray medium and coarse sand particles; slightly effervescent with few lime veins and coatings around root channels; moderately alkaline (pH 8.2); clear wavy boundary. (0 to 10 inches thick)
Bk2--53 to 65 inches; dark yellowish brown (10YR 4/4) silt loam, light yellowish brown (10YR 6/4) dry; massive; slightly hard, friable, slightly sticky and slightly plastic; many very fine pores; few coarse and very coarse sand particles; intermittently slightly effervescent with segregated lime; moderately alkaline (pH 8.1); abrupt smooth boundary. (0 to 20 inches thick)
2R--65 inches; basalt
TYPE LOCATION: Umatilla County, Oregon; 2.5 miles southeast of Athena on the Crow Field Pendleton Branch Experiment Station in SE1/4 section 28, T.4N., R.35E.
RANGE IN CHARACTERISTICS: The soils are usually moist but are dry for 45 to 90 days following the summer solstice and are moist during the winter months between depths of 4 and 12 inches. The mean annual soil temperature is 50 to 54 degrees F. The solum is 36 to 55 inches thick. Depth to bedrock is more than 40 inches and is commonly more than 60 inches. The profile ranges from slightly acid to neutral in the A horizons, neutral to mildly alkaline in the B horizons and mildly to strongly alkaline in the C horizons. Secondary lime occurs at depths below 43 inches or is absent. The mollic epipedon is 20 to 30 inches thick.
The A horizon has value of 2 or 3 moist, 4 or 5 dry and chroma of 1 or 2 moist and dry. It has moderate or strong granular structure in the Ap portion and weak or moderate granular or subangular blocky structure.
The Bw horizon has value of 3 or 4 moist, 4 through 6 dry and chroma of 2 through 4 moist and dry. It is silt loam with 18 to 27 percent clay. This horizon has weak or moderate; prismatic or subangular blocky structure.
The Bk horizon has hue of 10YR or 2.5Y, value of 5 through 7 dry, 4 through 6 moist, and chroma of 3 or 4 moist and dry. It is calcareous in some pedons but not in others.
COMPETING SERIES: These are the La Grande, Tucannon, and Wingville series. La Grande soils are moderately well drained, have 22 to 35 percent clay in the textural control section and are noncalcareous throughout. The Tucannon soils are 20 to 40 inches deep in bedrock. Wingville soils have high chroma mottles between 10 and 24 inches.
GEOGRAPHIC SETTING: The Athena soils are on canyon sides, hills, and plateaus. Elevations of 1,500 to 3,000 feet. Slopes are 0 to 70 percent. The soils formed in silty loess containing some volcanic ash.; The climate is temperate with hot dry summers and cool moist winters. The mean annual precipitation is 15 to 22 inches. Mean January temperature is about 30 degrees F., mean July temperature is 69 to 74 degrees F., and mean annual temperature is 48 to 52 degrees F. The frost-free season ranges from 130 to 190 days.
GEOGRAPHICALLY ASSOCIATED SOILS: These are the competing Tucannon soils and the Cheney, Gwin, Palouse, Reardon, Thatuna and Walla Walla soils. Cheney soils have secondary lime and have contrasting textures at depths of less than 40 inches. Gwin soils are less than 20 inches deep to bedrock. Thatuna soils have albic and argillic horizons. Palouse soils have base saturation of less than 75 percent in some part in the upper 30 inches. Walla Walla soils have mollic epipedon less than 20 inches thick.
DRAINAGE AND PERMEABILITY: Well-drained; slow to rapid runoff; moderate permeability.
USE AND VEGETATION: Largely cultivated with dryland wheat, barley and peas as dominant crops. Hay crops and pasture are also produced. Native vegetation consists of bluebunch wheatgrass, Idaho fescue, Sandberg bluegrass, balsamroot and western yarrow. Wild rose and other small shrubs grow on north slopes.
DISTRIBUTION AND EXTENT: Southeastern Washington, northeastern Oregon and north-central Idaho. The series is extensive.
MLRA OFFICE RESPONSIBLE: Portland, Oregon
SERIES ESTABLISHED: Patik Creek Area, Columbia County, Washington, l939.
REMARKS: Diagnostic horizons and features in this pedon include:
Mollic epipedon - from the surface to 26 inches (Ap, A1, and A2 horizons).
Cambic horizon - from 26 to 46 inches (Bw1 and Bw2 horizons).