LOCATION WOLFPEAK OREstablished Series
TAXONOMIC CLASS: Fine-loamy, mixed, superactive, mesic Ultic Palexeralfs
TYPICAL PEDON: Wolfpeak sandy loam, forested. (Colors are for moist soil unless otherwise noted.)
Oi--0.5 inch to 0; partially decomposed needles, leaves, and twigs.
A--0 to 4 inches; dark brown (10YR 3/3) sandy loam, brown (10YR 5/3) dry; strong fine granular structure; slightly hard, friable, slightly sticky and nonplastic; many very fine and fine and common medium and coarse roots; many very fine irregular pores; 13 percent gravel; moderately acid (pH 5.6); clear smooth boundary. (4 to 10 inches thick)
BA--4 to 11 inches; brown (7.5YR 4/4) sandy loam, very pale brown (10YR 7/4) dry; strong fine subangular blocky structure; slightly hard, friable, slightly sticky and nonplastic; many very fine and fine and common medium and coarse roots; many very fine irregular pores; 10 percent gravel; strongly acid (pH 5.4); clear wavy boundary. (6 to 10 inches thick)
Bt1--11 to 35 inches; yellowish brown (10YR 5/4) clay loam, very pale brown (10YR 7/4) dry; moderate medium and coarse subangular blocky structure; hard, firm, sticky and plastic; common very fine and fine and few medium and coarse roots; common very fine tubular pores; many distinct clay films in pores and on ped faces; 10 percent gravel and 3 percent cobbles; strongly acid (pH 5.4); gradual wavy boundary. (10 to 30 inches thick)
Bt2--35 to 60 inches; strong brown (7.5YR 5/6) clay loam, yellow (10YR 7/6) dry; moderate medium and coarse subangular blocky structure; hard, firm, sticky and plastic; few very fine and fine roots; common very fine tubular pores; many distinct clay films in pores and on ped faces; 10 percent gravel and 3 percent cobbles; strongly acid (pH 5.4).
TYPE LOCATION: Jackson County, Oregon; about 2,400 feet east and 500 feet south of the northwest corner of sec. 21, T. 33 S., R. 3 W., W.M.
RANGE IN CHARACTERISTICS: These soils are usually moist but are dry in the moisture control section for 60 to 90 consecutive days in the four months that follow the summer solstice. The mean annual soil temperature ranges from 47 to 54 degrees F. The solum is over 60 inches thick. Depth to bedrock is greater than 60 inches. The particle-size control section averages 20 to 35 percent clay, 5 to 20 percent gravel, and 0 to 5 percent cobbles. It is strongly to slightly acid throughout.
The A and BA horizon have hue of 7.5YR or 10YR, value of 3 through 5 moist, 4 through 7 dry, and chroma of 2 through 4 moist and dry. The A horizon has 2 to 6 percent organic matter.
The Bt horizon has hue of 10YR, 7.5YR, or 5YR, value of 4 through 6 moist, 5 through 7 dry, and chroma of 4 through 8 moist and dry. It has 5 to 20 percent gravel and 0 to 5 percent cobbles. It is a loam, clay loam or gravelly clay loam. Hue of 10YR occurs only in the upper part.
COMPETING SERIES: This is the Jafa series. Jafa soils have a mean annual soil temperature of 54 to 59 degrees F.
GEOGRAPHIC SETTING: Wolfpeak soils are on hillslopes and old slump benches at elevations of 700 to 3,500 feet. These soils formed in colluvium and residuum weathered from granodiorite. The mean annual precipitation is 40 to 50 inches. The mean annual temperature is 45 to 52 degrees F. The frost-free period is 100 to 200 days. Slopes range from 3 to 60 percent.
GEOGRAPHICALLY ASSOCIATED SOILS: These are the Josephine, Pollard, Speaker, and Tethrick soils. Tethrick soils lack an argillic horizon. Josephine and Pollard soils have base saturation of less than 35 percent. Speaker soils are 20 to 40 inches to bedrock.
DRAINAGE AND PERMEABILITY: Well drained; medium to rapid runoff; moderately slow permeability.
USE AND VEGETATION: These soils are used for timber production and pasture. Native vegetation includes an overstory of Douglas fir, California black oak, ponderosa pine, sugar pine, incense cedar, and Pacific madrone. Understory includes western fescue, cascade Oregongrape, whipplevine, golden chinkapin, creambush oceanspray, poison oak, and canyon live oak.
DISTRIBUTION AND EXTENT: Southwestern Oregon. The series is not extensive.
MLRA SOIL SURVEY REGIONAL OFFICE (MO) RESPONSIBLE: Davis, California
SERIES ESTABLISHED: Jackson County Area, Oregon, 1988.
REMARKS: The activity class was added to the classification in March of 2003. Competing series were not checked at that time. - ET
Diagnostic horizons and features:
- Ochric epipedon - moist value and chroma of 4 at 4 to ll inches; dry value of 7.
- Argillic horizon - from 11 to 60 inches.
- Assume base saturation of 50 to 75 percent in upper 30 inches of argillic horizon.
- Mollic intergrade - moist value of 3 from 0 to 4 inches and 2 to 6 percent organic matter.