LOCATION DARKCANYON OREstablished Series
TAXONOMIC CLASS: Loamy-skeletal, mixed, superactive, mesic Xeric Haplocambids
TYPICAL PEDON: Darkcanyon extremely channery loam - on a 70 percent convex southeast-facing slope, rangeland. (Colors are for dry soil unless otherwise noted.)
A1--0 to 7 inches; light gray (10YR 7/2) extremely channery loam, grayish brown (10YR 5/2) moist; weak very fine and fine subangular blocky structure; slightly hard, friable, nonsticky and nonplastic; common fine and medium roots; many very fine and fine tubular pores; 50 percent schist channers and 10 percent schist flagstones; neutral (pH 7.2); clear wavy boundary. (4 to 8 inches thick)
A2--7 to 13 inches; light grayish brown (10YR 6/2) extremely channery clay loam, grayish brown (10YR 5/2) moist; weak fine subangular blocky structure; hard, firm, slightly sticky and slightly plastic; common fine and medium roots; many fine and very fine tubular pores; 60 percent schist channers and 5 percent schist flagstones; neutral (pH 7.2); gradual wavy boundary. (5 to 10 inches thick)
Bw1--13 to 23 inches; light grayish brown (10YR 6/2) extremely channery clay loam, dark grayish brown (10YR 4/2) moist; weak fine subangular blocky structure; hard, firm, slightly sticky and slightly plastic; common fine roots; many fine and very fine tubular pores; 65 percent schist channers and 5 percent schist flagstones; neutral (pH 7.2); gradual wavy boundary. (8 to 12 inches thick)
Bw2--23 to 30 inches; light grayish brown (10YR 6/2) extremely channery clay loam, dark grayish brown (10YR 4/2) moist; weak fine subangular blocky structure; hard, firm, slightly sticky and slightly plastic; common fine roots; many fine and very fine tubular pores; 70 percent schist channers; mildly alkaline (pH 7.4); gradual wavy boundary. (3 to 10 inches thick)
R--30 inches; highly fractured schist.
TYPE LOCATION: Baker County, Oregon; located 100 feet above the Burnt River Canyon Road in the SE1/4NE1/4NE1/4NE1/4 sec. 31, T. 11 S., R. 42 E.
RANGE IN CHARACTERISTICS: These soils are dry in all parts of the moisture control section for more than half the time (cumulative) that the soil temperature is above 41 degrees F. The mean annual soil temperature is 49 to 53 degrees F. Depth to bedrock is 20 to 40 inches. The particle-size control section averages 60 to 75 percent rock fragments and 25 to 35 percent clay.
The A horizon has value of 6 or 7 dry, 3 through 5 moist, and chroma of 2 or 3 moist and dry. It has 45 to 65 percent channers and 5 to 15 percent flagstones.
The Bw horizon has value of 6 or 7 dry, 4 or 5 moist, and chroma of 2 through 4 moist and dry. It is loam or clay loam, averaging 20 to 30 percent clay. It has 50 to 70 percent channers and 0 to 10 percent flagstones.
COMPETING SERIES: These are the Finley, Kiona, Mackey, Minat, Nibbs, Veet and Veta series. The Finley, Kiona, Minat, Nibbs, Veet and Veta soils are over 40 inches deep. The Mackey soils are calcareous below 10 inches.
GEOGRAPHIC SETTING: The Darkcanyon soils are in convex positions on south-facing side slopes on hills. Slopes are 30 to 80 percent. Elevations range from 2,000 to 4,000 feet. The soils formed in colluvium and residuum derived dominantly from schist and graywacke. The mean annual precipitation is 9 to 12 inches. The mean annual temperature is 45 to 50 degrees F. The frost-free period is 110 to 130 days.
GEOGRAPHICALLY ASSOCIATED SOILS: These are the Chambeam, Harlow, Lostbasin, Sinker, Snaker, and Snell soils. The Chambeam, Lostbasin, and Sinker soils have frigid soil temperatures. Chambeam and Sinker have mollic epipedons and are pachic. Harlow and Snell are on adjacent basalt uplands and are clayey-skeletal. Lostbasin soils are moderately deep to bedrock. Snaker soils are shallow to bedrock.
DRAINAGE AND PERMEABILITY: Well drained. Runoff is rapid. Permeability is moderate.
USE AND VEGETATION: These soils are used for rangeland. The native vegetation is bluebunch wheatgrass, Sandberg bluegrass, gray rabbitbrush, spiny hopsage, Snaker River greasebush, and lomatium.
DISTRIBUTION AND EXTENT: Eastern Oregon. The series is of moderate extent.
MLRA OFFICE RESPONSIBLE: Portland, Oregon
SERIES ESTABLISHED: Baker County Area, Oregon, 1988.
REMARKS: Diagnostic horizons and features in this pedon are:
Ochric epipedon - the zone from the surface of the soil to a depth of 13 inches.
Cambic horizon - the zone from 13 to 30 inches (Bw1, Bw2 horizons).
Xerollic - these soils have more organic matter than Typic, and their moisture regime borders on xeric.
Coarse fragments are channers and flagstones.
NSTH 17, RECLASSIFICATION ONLY, 3/95