LOCATION HAMMERSLEY OREstablished Series
TAXONOMIC CLASS: Fine, mixed, superactive Pachic Argicryolls
TYPICAL PEDON: Hammersley loam, forested, on a 21 percent north facing slope. (Colors are for moist soil unless otherwise noted.)
Oi--3 inches to 0; white fir needles.
A1--0 to 2 inches; very dark grayish brown (10YR 3/2) loam, dark grayish brown (10YR 4/2) dry; weak very fine granular structure; soft, very friable, nonsticky and nonplastic; many roots; many irregular pores; 5 percent gravel; neutral (pH 6.8); abrupt smooth boundary. (2 to 4 inches thick.)
A2--2 to 15 inches; very dark grayish brown (10YR 3/2) loam, grayish brown (10YR 5/2) dry; moderate very fine and fine granular structure; soft, very friable, slightly sticky and slightly plastic; many roots; many irregular pores; 5 percent gravel; neutral (pH 6.6); clear wavy boundary. (7 to 18 inches thick)
Bt1--15 to 24 inches; very dark grayish brown (10YR 3/2) clay loam, brown (10YR 5/3) dry; moderate fine subangular blocky structure; slightly hard, firm, slightly sticky and plastic; many roots; common tubular pores; few distinct clay films on peds and in pores; 10 percent gravel; slightly acid (pH 6.4); gradual wavy boundary. (7 to 14 inches thick)
Bt2--24 to 35 inches; dark brown (10YR 3/3) clay, grayish brown (10YR 5/2) dry; moderate fine and medium subangular blocky structure; hard, firm, sticky and plastic; few roots; common tubular pores; common distinct clay films on peds and in pores; 10 percent gravel; slightly acid (pH 6.4); gradual wavy boundary. (10 to 21 inches thick)
C--35 to 50 inches; dark yellowish brown (10YR 3/4) cobbly clay, brown (10YR 5/3) dry; massive; hard, firm, slightly sticky and slightly plastic; few roots; few irregular pores; 15 percent cobbles, 10 percent gravel; slightly acid (pH 6.3); abrupt wavy boundary. (10 to 18 inches)
Cr--50 inches; highly weathered tuffaceous bedrock.
TYPE LOCATION: Lake County, Oregon; SW1/4, SW1/4 of section 33, T. 37. S, R. 21 E.
RANGE IN CHARACTERISTICS: The soils are moist in the winter and spring and are dry for 45 to 60 consecutive days after the summer solstice. The mean annual soil temperature is 40 to 45 degrees F. The mean summer soil temperature is 44 to 47 degrees F. The mollic epipedon is 16 to 30 inches thick. Depth to bedrock is 40 to 60 inches. The particle-size control section averages 10 to 25 percent rock fragments. It has 35 to 50 percent clay.
The A horizon has value of 2 or 3 when moist and 4 or 5 when dry, and chroma of 2 or 3 when moist and dry.
The Bt horizon has hue of 7.5YR or 10YR, value of 3 or 4 when moist and 4 or 5 when dry, and chroma of 2 to 4 when moist and dry. It is clay loam and clay. Rock fragments range from 0 to 10 percent cobbles and stones and 5 to 25 percent gravel.
The C horizon has value of 3 or 4 moist and 4 or 5 when dry, and chroma of 3 or 4 when moist and dry. It is clay and clay loam. Rock fragments range from 10 to 30 percent cobbles and stones and 5 to 15 percent gravel.
COMPETING SERIES: This is the Telefono series. Telefono soils are moderately deep to bedrock.
GEOGRAPHIC SETTING: Hammersley soils are on mountainsides at elevations of 6,300 to 7,200 feet. Slopes are 15 to 70 percent. The soils formed in colluvium and residuum weathered primarily from pyroclastic rocks. The climate is cold and moist in winters and cool and dry in summers. The annual precipitation is 30 to 34 inches. The mean annual temperature is 41 to 43 degrees F. The frost-free period is 20 to 50 days.
GEOGRAPHICALLY ASSOCIATED SOILS: These are the Chocktoot, Hallihan, Kittleson and Mound soils. Chocktoot soils are loamy-skeletal. The Hallihan and Kittleson soils lack a mollic epipedon. Mound soils have a frigid soil temperature regime.
DRAINAGE AND PERMEABILITY: well drained; slow permeability.
USE AND VEGETATION: The soils are used primarily for timber production, watershed, wildlife habitat, and recreation. Vegetation is primarily white fir, sticky currant and wheeler bluegrass.
DISTRIBUTION AND EXTENT: South central Oregon, MLRA 21. The series is of small extent.
MLRA SOIL SURVEY REGIONAL OFFICE (MO) RESPONSIBLE: Davis, California
SERIES ESTABLISHED: Lake County, Oregon; Southern Part 1991.
REMARKS: Diagnostic horizons and features recognized in this pedon are:
Mollic epipedon (pachic) - 0 to 24 inches (A1, A2, Bt1 horizons)
Argillic horizon - 15 to 35 inches (Bt1, Bt2 horizons)
Paralithic contact - The boundary at 50 inches.
ADDITIONAL DATA: U.S. Forest Service vegetative site CW-C4-11.