LOCATION JOJO OREstablished Series
TAXONOMIC CLASS: Medial-skeletal, amorphic Typic Vitricryands
TYPICAL PEDON: Jojo very stony sandy loam - on a 14 percent west facing slope, woodland. ( Colors are for moist soil unless otherwise noted.)
0i--2 inches to 0; organic layer of needles and twigs.
A--0 to 7 inches; dark brown (7.5YR 3/3) very stony sandy loam, brown (7.5YR 4/3) dry; weak fine and medium subangular blocky parting to weak fine granular structure; soft, friable, nonsticky and nonplastic; many very fine, fine and few medium roots; many very fine, fine and few medium irregular pores; 35 percent stones, 10 percent cobbles and 10 percent gravel; moderately acid (pH 5.8); clear wavy boundary.(6 to 9 inches thick)
2C1--7 to 18 inches; reddish brown (5YR 4/4) very gravelly sandy loam, brown (7.5YR 5/4) dry; massive; hard, firm, nonsticky and nonplastic; common very fine and fine roots; common very fine and fine tubular pores; 40 percent gravel, 10 percent cobbles and 5 percent stones; moderately acid (pH 5.6); clear smooth boundary.(9 to 13 inches thick)
2C2--18 to 28 inches; reddish brown (5YR 4/4) extremely gravelly sandy loam, light brown (7.5YR 6/4) dry; massive; hard, firm, nonsticky and nonplastic; few very fine and fine roots; few very fine and fine tubular pores; 50 percent gravel and 20 percent cobbles; moderately acid (pH 5.6); clear wavy boundary.(8 to 12 inches thick)
2C3--28 to 32 inches; reddish brown (2.5YR 4/4) extremely gravelly loamy sand, light reddish brown (5YR 6/4) dry; massive; hard, firm, nonsticky and nonplastic; few very fine roots; few very fine tubular pores; 55 percent gravel and 10 percent cobbles; strongly acid (pH 5.5); abrupt wavy boundary.(3 to 6 inches thick)
2Cr1--32 to 36 inches; dusky red (2.5YR 3/2) pyroclastic ash flow. (4 to 6 inches thick)
2Cr2--36 to 60 inches; very dark brown (10YR 2/2) pyroclastic ash flow.
TYPE LOCATION: Marion County, Oregon: 2000 feet north and 100 feet east of the SW corner of section 25, T. 8 S., R. 8 E.(Warm Springs Indian Reservation) (Latitude 44 degrees, 45 minutes, 45 seconds N., Longitude 121 degrees, 39 minutes, 35 seconds E.).
RANGE OF CHARACTERISTICS: These soils are usually moist and are not dry in all parts of the soil moisture control section for as long as 45 consecutive days in the four months that follow the summer solstice. The mean annual soil temperature is 36 to 38 degrees F. Depth to pyroclastic ash flow or andesite is 20 to 40 inches. The particle-size control section has 40 to 80 percent rock fragments and averages less than 15 percent clay. Phosphate retention is more than 85 percent and the acid oxalate extractable aluminum plus one-half the acid oxalate extractable iron is between 2 and 5 percent in the less than 2.0 mm fraction. There is 25 to 40 percent volcanic glass and glass aggregate in the 0.02 to 2.0 mm fraction. The 15-bar water is 12 to 15 percent on air dried samples and less than 30 percent on undried samples. It has a moist bulk density of 0.80 to 0.90 g/cc. It is moderately acid to strongly acid.
The A horizon has hue of 7.5YR or 10YR, value of 3 or 4 moist and dry and chroma of 2 through 4 moist and dry. It is sandy loam with 0 to 30 percent boulders, 10 to 40 percent stones, 5 to 10 percent cobbles, and 5 to 10 percent gravel.
The 2C horizon has hue of 7.5YR, 5YR or 2.5YR, value of 3 or 4 moist, 4 through 6 dry and chroma of 3 or 4 moist and dry. It is sandy loam or loamy sand. Rock fragments range from 45 to 80 percent of which 35 to 55 percent are gravel, 10 to 20 percent are cobbles and 0 to 5 percent are stones.
The 2Cr horizon is pyroclastic ash flow or highly weathered andesite.
COMPETING SERIES: There are no competing series.
GEOGRAPHIC SETTING: Jojo soils are on strongly sloping to very steep side slopes of mountains. Elevation ranges from 4000 to 6400 feet. Slopes are 0 to 70 percent. The soil formed in residuum and colluvium derived dominantly from pyroclastic ash flow and andesite. The climate is characterized by cold and wet winters and cool and moist summers. The mean annual precipitation is 70 to 110 inches. The mean annual temperature is 34 to 38 degrees F. The frost-free period is 10 to 45 days.
GEOGRAPHICALLY ASSOCIATED SOILS: These are the Pinhead and Piumpsha soils. Piumsha soils are medial, have an argillic horizon, and are in concave positions on side slopes of mountains. Pinhead soils are very deep to bedrock and are on side slopes of mountains.
DRAINAGE AND PERMEABILITY: Somewhat excessively drained. Permeability is moderately rapid to rapid.
USE AND VEGETATION: These soils are used for timber production, watershed and wildlife habitat. The native vegetation is mountain hemlock, lodgepole pine, subalpine fir, and Douglas fir with an understory of common beargrass, big huckleberry, and grouse blueberry.
DISTRIBUTION AND EXTENT: North-central Oregon; MLRA 3. The soils of this series are moderately extensive.
MLRA SOIL SURVEY REGIONAL OFFICE (MO) RESPONSIBLE: Portland, Oregon
SERIES ESTABLISHED: Marion County (Warm Springs Indian Reservation), Oregon, 1993.
REMARKS: Diagnostic horizons and features in this pedon include:
Ochric epipedon
Andic soil properties - from surface to 32 inches. Based on lab data from similar soils.
Particle-size control section - from surface to 32 inches (A, 2C1, 2C2 horizons).
Depth to bedrock - 32 inches (2Cr1)