LOCATION WOODCOCK OR+CAEstablished Series
TAXONOMIC CLASS: Medial-skeletal, amorphic Typic Haplocryands
TYPICAL PEDON: Woodcock stony medial loam--forestland. (Colors are for moist soil unless otherwise noted.)
Oi--0 to 1 inch; slightly decomposed plant material of needles and twigs.
A1--1 to 5 inches; dark reddish brown (5YR 3/2) stony medial loam, reddish brown (5YR 4/3) dry; moderate medium and fine granular structure; soft, friable, slightly sticky and slightly plastic; many very fine and fine roots; many fine irregular pores; 5 percent gravel and 5 percent cobbles; stones covering 5 percent of surface; neutral (pH 6.8); abrupt smooth boundary.
A2--5 to 17 inches; dark reddish brown (5YR 3/2) very gravelly medial loam, reddish brown (5YR 4/3) dry; weak fine and medium granular structure; soft, friable, slightly sticky and slightly plastic; many fine roots; many fine irregular pores; 30 percent gravel and 5 percent cobbles; neutral (pH 7.0); clear smooth boundary.
BA--17 to 21 inches; dark reddish brown (5YR 3/3) very gravelly medial clay loam, reddish brown (5YR 4/4) dry; moderate medium and fine subangular blocky structure; slightly hard, friable, moderately sticky and slightly plastic; common medium, fine, and very fine roots; common fine tubular pores; 50 percent gravel and 5 percent cobbles; slightly acid (pH 6.4); clear wavy boundary. (Combined thickness of the A and BA horizons is 16 to 30 inches).
Bt1--21 to 33 inches; dark reddish brown (5YR 3/4) very gravelly medial clay loam, reddish brown (5YR 4/4) dry moderate medium and fine subangular blocky structure; hard, friable, moderately sticky and moderately plastic; common medium and few fine roots; common fine tubular pores; few faint clay films on faces of peds; 50 percent gravel and 5 percent cobbles; slightly acid (pH 6.2); clear smooth boundary.
Bt2--33 to 40 inches; dark reddish brown (5YR 3/4) very gravelly medial clay loam, reddish brown (5YR 4/4) dry; moderate medium and fine subangular blocky structure; slightly hard, friable, moderately sticky and moderately plastic; common medium and few fine roots; common fine tubular pores; common faint clay films on faces of peds; 50 percent gravel and 5 percent cobbles; slightly acid (pH 6.1); clear smooth boundary. (Combined thickness of Bt horizons is 15 to 25 inches).
BC1--40 to 49 inches; dark reddish brown (2.5YR 2.5/4) gravelly medial clay loam, reddish brown (2.5YR 4/4) dry; weak medium and fine subangular blocky structure; slightly hard, friable, moderately sticky and slightly plastic; few medium roots; common fine tubular pores; 15 percent gravel; slightly acid (pH 6.1); clear smooth boundary.
BC2--49 to 63 inches; dark reddish brown (2.5YR 2.5/4) gravelly medial clay loam, dusky red (2.5YR 3/2) dry; massive; soft, friable, moderately sticky and slightly plastic; few medium roots; few fine tubular pores; 15 percent gravel; moderately acid (pH 5.8).
TYPE LOCATION: Jackson County, Oregon; near the county line with Klamath County, Oregon; about 1,300 feet south and 1,800 feet west of the northeast corner of section 27, T. 39 S., R. 4 E.
RANGE IN CHARACTERISTICS:
Soil moisture - The soil moisture control section is dry for 30 to 45 consecutive days; Udic.
The solum has andic soil properties throughout its thickness. Acid oxalate aluminum plus one-half the iron is 3 to 5 percent. Phosphate retention is 75 to 100 and glass is 15 to 30 percent. The 15bar water dry is 13 to 30 percent and 15bar water moist is 25 to 35 percent. Acid oxalate silica is 2 to 3 percent.
Mean annual soil temperature - 41 to 47 degrees F.
Mean summer soil temperature - Without an Oi horizon 50 to 59 degrees F.; with an Oi horizon 44 to 47 degrees F.
Mollic epipedon thickness - 16 to 30 inches.
Base saturation by sum of bases is 50 to 75 percent throughout the profile.
Depth to bedrock - 40 to more than 60 inches.
A and BA horizons - Hue: 5YR through 10YR.
Value: 2 or 3 moist, 3 through 5 dry.
Chroma: 2 through 4 moist, 1 through 4 dry.
Rock fragments: 5 to 50 percent gravel, 0 to 15 percent cobbles and stones. All fragments are subrounded.
Reaction: Slightly acid or neutral.
Organic matter content: 5 to 10 percent in the A1 horizon, 1 to 5 percent in the A2 and BA horizons.
Bt horizons - Hue: 5YR through 10YR.
Value: 2 through 4 moist, 4 through 6 dry.
Chroma: 2 through 4, moist or dry.
Texture: Very gravelly medial clay loam, very gravelly medial loam, extremely gravelly medial loam, or very cobbly medial loam.
Clay content: 25 to 35 percent much of which is in nondispersible sand-sized aggregates.
Rock fragments: 45 to 55 percent gravel, 5 to 20 percent cobbles and stones. All fragments are subrounded.
Reaction: Slightly acid or neutral.
BC horizon - Hue: 5YR through 10YR.
Value: 2 through 4 moist, 4 through 6 dry.
Chroma: 2 through 4, moist or dry.
Texture: Very cobbly medial loam, extremely cobbly medial loam, gravelly medial clay loam, very gravelly medial loam, or extremely gravelly medial loam. Rock fragments are subrounded.
Clay content: 15 to 30 percent.
Reaction: Moderately acid or slightly acid.
COMPETING SERIES: These are the Divers, Highcamp, Holderman, Kinzel, Ohana and Otwin soils. Holderman, Otwin and Ohana soils are moderately deep to a restrictive feature. Kinzel soils have a umbric epipedon. Oatman soils have a ochric epipedon and cambic horizon. Divers and Highcamp soils have less than 18 percent field estimated clay.
GEOGRAPHIC SETTING: Woodcock soils are on mountains and plateaus. These soils formed in colluvium and mudflows from glacial outwash derived from volcanic rocks and volcanic ash. Slopes are 1 to 60 percent. Elevations range from 3,800 to 6,500 feet. The climate is subhumid-continental with cold, moist winters and cool, dry summers. The mean annual precipitation is 18 to 45 inches. The mean January temperature about is 26 degrees F., the mean July temperature is about 59 degrees F., and the mean annual temperature is 39 to 45 degrees F. The frost-free period is less than 100 days.
GEOGRAPHICALLY ASSOCIATED SOILS: These are the Pokegema, Lorella, Mound, Royst, Yawhee and competing Oatman soils. Lorella soils have very gravelly clay argillic horizons and have bedrock at depths of 10 to 20 inches. Mound soils have argillic horizons averaging 35 to 45 percent clay and less than 35 percent rock fragments. Royst soils are on associated south-facing slopes and have frigid soil temperature that are 20 to 40 inches deep to bedrock and are clayey-skeletal. Yawhee soils are ashy in the upper part of the control section. Pokegema soils are medial.
DRAINAGE AND PERMEABILITY: Well drained; low to high surface runoff; moderate permeability.
USE AND VEGETATION: Woodcock soils are used for timber production, wildlife habitat, livestock grazing, and recreation. The vegetation is a forest canopy of mainly white fir with ponderosa pine, shasta red fir, sugar pine, Douglas-fir, and incense cedar.
DISTRIBUTION AND EXTENT: Southern Oregon and northern California; MLRA 3 and 21. These soils are extensive.
MLRA OFFICE RESPONSIBLE: Portland, Oregon
SERIES ESTABLISHED: Modoc County (Alturas Area), California, 1976.
REMARKS: In 2007 the series type location was moved to an area where the vegetation was more representative of a cryic temperature regime. The original series type location is now considered frigid. The pedon is now the type location for the Ryespur series. The andic soil properties and Andisol classification are based on NSSL data from the similar Oatman series.
Diagnostic horizons and features recognized in this pedon are:
Andic soil properties are based on laboratory data from the similar Oatman soils.
Organic soil material - The zone from the soil surface to 1 inch (Oi horizon).
Mollic epipedon - The zone from 0 to 21 inches (Oi, A1, A2, and BA horizons).
Argillic horizon - The zone from 21 to 40 inches (Bt1 and Bt2 horizons).
Particle-size control section - The zone from 1 to 41 inches averages 43 percent rock fragments.