LOCATION BRANNAN OREstablished Series
TAXONOMIC CLASS: Ashy over loamy-skeletal, glassy over isotic, frigid Typic Vitrixerands
TYPICAL PEDON: Brannan channery ashy silt loam, woodland. (Colors are for moist soil unless otherwise noted.)
Oi--0 to 1 inch; partially decomposed needles, twigs, and grass.
A--1 to 5 inches; very dark grayish brown (10YR 3/2) channery ashy silt loam, grayish brown (10YR 5/2) dry; weak fine granular structure; soft, very friable, nonsticky and nonplastic; many very fine and fine roots; many very fine and fine irregular pores; 30 percent channers; neutral (pH 7.0); clear wavy boundary. (3 to 8 inches thick)
Bw1--5 to 15 inches; dark yellowish brown (10YR 3/4) channery ashy silt loam, yellowish brown (10YR 5/4) dry; weak fine subangular blocky structure parting to weak fine granular; soft, very friable, nonsticky and nonplastic; many very fine and fine and few medium roots; many very fine and fine tubular pores; 30 percent channers; neutral (pH 7.0); abrupt wavy boundary. (9 to 13 inches thick)
2Bw2--15 to 29 inches; brown (10YR 4/3) very channery sandy clay loam, pale brown (10YR 6/3) dry; weak fine subangular blocky structure; hard, friable, slightly sticky and slightly plastic; common fine and medium roots; common fine tubular pores; 40 percent channers and 10 percent flagstones; neutral (pH 6.8); gradual wavy boundary. (10 to 20 inches thick)
2C--29 to 49 inches; brown (10YR 5/3) very channery sandy clay loam, pale brown (10YR 6/3) dry; massive; hard, friable, slightly sticky and slightly plastic; few fine and medium roots; common fine tubular pores; 40 percent channers and 15 percent flagstones; neutral (pH 6.8); clear wavy boundary. (14 to 22 inches thick)
2R--49 inches; highly fractured schist.
TYPE LOCATION: Baker County, Oregon; about 1/2 mile west of Dooley Mountain summit in the SW1/4SE1/4NE1/4 sec. 25, T. 11 S., R. 39 E.
RANGE IN CHARACTERISTICS: These soils are usually moist, but are dry in the moisture control section for 45 to 60 consecutive days following the summer solstice. The mean annual soil temperature ranges from 43 to 47 degrees F. Depth to bedrock is 40 to 60 inches. The thickness of the volcanic ash mantle is 14 to 20 inches and contains 60 to 70 percent volcanic glass and glass aggragate.
The A horizon has value of 2 or 3 moist, 4 or 5 dry, and chroma of 2 or 3 moist and dry. It has 15 to 30 percent channers and 0 to 10 percent flagstones.
The Bw1 horizon has value of 3 or 4 moist, 4 or 5 dry, and chroma of 3 or 4 moist and dry. It has 15 to 35 percent channers and 0 to 10 percent flagstones.
The 2B horizon has value of 4 or 5 moist, 5 or 6 dry, and chroma of 3 or 4 moist and dry. The texture is sandy loam or sandy clay loam, and has 30 to 50 percent channers and 5 to 15 percent flagstones. Percent clay is 15 to 30 percent.
The 2C horizon has value of 5 or 6 moist, 6 or 7 dry, and chroma of 3 or 4 moist and dry. It is very channery sandy loam or very channery sandy clay loam, and has 30 to 50 percent channers and 5 to 15 percent flagstones.
COMPETING SERIES: These are the Capoose, Crackler, Elbowlake, Farway, Kellerbutte, Natapoc, Nevine, Olot, Rouen, Saska, and Vingulch series. Capoose, Olot, Rouen, and Vingulch soils are moderately deep to bedrock. Crackler soils are loam, silty clay loam, and clay loam in the lower part of the particle-size control section. Elbowlake, Natapoc, and Nevine soils have 2Cd horizons. Farway, Kellerbutte, and Saska soils are very deep.
GEOGRAPHIC SETTING: These soils are on north and east-facing mountain side slopes. Slopes are 2 to 70 percent. Elevation is 4,000 to 6,000 feet. They formed in colluvium derived from schist and have a mantle of volcanic ash. The mean annual precipitation is 20 to 35 inches. The climate is characterized by cold and wet winters and hot and dry summers. The mean annual temperature is 40 to 45 degrees F. The frost-free period is 30 to 60 days.
GEOGRAPHICALLY ASSOCIATED SOILS: These are the Chambeam, Piersonte, Sinker, and Sisley series. The Chambeam and Sinker soils have a mollic epipedon and are on hills at lower elevations. The Piersonte soils are formed in similar geologic material but lack the volcanic ash mantle, and have a mollic epipedon. Sisley soils are on adjacent south-facing slopes and lack the volcanic ash mantle.
DRAINAGE AND PERMEABILITY: Well drained; runoff is slow to rapid; permeability is moderate.
USE AND VEGETATION: These soils are used mainly for woodland. The native vegetation is Douglas fir, grand fir, western larch, ponderosa pine, and lodgepole pine, with an understory of elk sedge, pinegrass, princes pine, low Oregon grape, spirea, big huckleberry, myrtle pachystima, twinflower, pyrola, violet, western rattlesnake plantain, and heartleaf arnica.
DISTRIBUTION AND EXTENT: Northeastern Oregon. The soils are inextensive.
MLRA SOIL SURVEY REGIONAL OFFICE (MO) RESPONSIBLE: Bozeman, Montana
SERIES ESTABLISHED: Baker County Area, Oregon, 1988.
REMARKS: This draft reflects a change in mineralogy from mixed to glassy over isotic.
Diagnostic horizons and features in this pedon include:
Vitrixerand feature - The upper part of the profile contains over 60 percent glass and glass aggregate and has more than 0.4 percent acid oxylate Al + 1/2Fe; this is based on lab data from other soils in the area.
Ochric epipedon - based on a moist chroma of 4 from 5 to 15 inches (Bw1 horizon).
Cambic horizon - the zone from approximately 5 to 29 inches (Bw1, 2Bw2 horizons).