LOCATION CHOCKNOTT ORTentative Series
TAXONOMIC CLASS: Ashy, glassy, nonacid Typic Cryaquands
TYPICAL PEDON: Chocknott ashy sandy loam supporting the tufted hairgrass plant association on a 2 percent slope at 5,131 feet elevation. When described on 16 September 1998 the soil was moist from 0 to 32 inches and wet from 32 to 63 inches. (Colors are for dry soil unless otherwise noted.)
A1--0 to 6 inches; grayish brown (10YR 5/2) ashy sandy loam, very dark grayish brown (10YR 3/2) moist; moderate very fine granular structure; soft, very friable, slightly sticky and slightly plastic; many very fine and fine roots; many very fine interstitial pores; moderately acid (pH 5.6); clear smooth boundary. (4 to 12 inches thick)
A2--6 to 17 inches; grayish brown (10YR 5/2) ashy sandy loam, very dark grayish brown (10YR 3/2) moist; weak coarse subangular blocky structure parting to strong fine granular; slightly hard, very friable, slightly sticky and slightly plastic; many very fine, common fine and few medium roots; many very fine irregular pores; 10 percent pumice paragravel; few fine distinct dark yellowish brown (10YR 4/4) iron masses in matrix adjacent to medium roots, dark yellowish brown (10YR 3/4) moist; moderately acid (pH 5.8); clear smooth boundary. (4 to 16 inches thick)
Bwc--17 to 30 inches; pale brown (10YR 6/3) paragravelly ashy coarse sandy loam, brown (10YR 5/3) moist; weak coarse subangular blocky structure; slightly hard, very friable, slightly sticky and slightly plastic; common very fine and fine roots; many very fine and few fine tubular pores; 15 percent pumice paragravel; common fine distinct yellowish brown (10YR 5/6) iron masses in matrix and center of paragravel, dark yellowish brown (10YR 4/4) moist; many fine prominent black (2.5Y 2.5/1) dry or moist manganese nodules in matrix; moderately acid (pH 5.8); clear smooth boundary. (8 to 20 inches thick)
BCc--30 to 63 inches; very pale brown (10YR 7/4) paragravelly ashy loamy coarse sand, light olive brown (2.5Y 5/4) moist; massive; slightly hard, very friable, non-sticky and non-plastic; few fine roots; many very fine and common fine tubular pores; 30 percent pumice paragravel; many coarse distinct yellowish brown (10YR 5/6) iron masses in matrix, prominent brown (7.5YR 4/4) moist; many fine prominent black (2.5Y 2.5/1) manganese nodules in matrix, distinct black (2.5Y 2.5/1) moist; moderately acid (pH 6.0).
TYPE LOCATION: Klamath County, Oregon; about 7 miles east of Chemult; about 2430 feet east and 210 feet south of the northwest corner of section 22, T. 27 S., R. 9 E. (Latitude 43 degrees, 13 minutes, 30 seconds North, Longitude 121 degrees, 38 minutes, 12 seconds West)
RANGE IN CHARACTERISTICS:
Mean annual soil temperature - 35 to 40 degrees F
Mean winter soil temperature - 32 to 35 degrees F
Mean summer soil temperature - 40 to 45 degrees F without an O horizon
Depth to aquic conditions - occur at soil surface
Umbric epipedon 14 to 23 inches thick
A1 horizon
Thickness: 4 to 12 inches
Hue: 10YR or 2.5Y dry or moist
Value: 4 or 5 dry; 2, 2.5 or 3 moist
Chroma: 1 or 2 dry; 1, 2 or 3 moist
Texture: ashy sandy loam or medial loam
Clay content: 10 to 20 percent
Pumice paragravel content: 0 to 15 percent (most passes #4 sieve with crushing)
Volcanic glass content: 50 to 90 percent in the 0.02 to 2.0 mm fraction
Ammonium oxalate extractable Al plus 1/2 Fe: 0.4 to 1.0 percent
Phosphate retention: 25 to 35 percent
15 bar water content of air-dried samples: 8 to 18 percent
Organic matter content: 6 to 10 percent
Redoximorphic features: absent to common, fine iron masses
Reaction: strongly acid or moderately acid (pH 5.1 to 6.0)
A2 horizon
Depth to: 4 to 12 inches
Thickness: 4 to 16 inches
Hue: 10YR or 2.5Y dry or moist
Value: 4 or 5 dry; 2, 2.5 or 3 moist
Chroma: 1, 2 or 3 dry; 1 or 2 moist
Texture: ashy sandy loam, ashy coarse sandy loam or medial loam
Clay content: 10 to 20 percent
Pumice paragravel content: 5 to 35 percent (most passes the #4 sieve without crushing)
Volcanic glass content: 50 to 90 percent in the 0.02 to 2.0 mm fraction
Ammonium oxalate extractable Al plus 1/2 Fe: 0.4 to 1.0 percent
Phosphate retention: 25 to 35 percent
15 bar water content of air-dried samples: 8 to 18 percent
Organic matter content: 2 to 6 percent
Redoximorphic features: few or common, fine or medium iron masses
Reaction: moderately acid or slightly acid (pH 5.6 to 6.5)
Bwc horizon
Depth to: 12 to 20 inches
Thickness: 8 to 20 inches
Hue: 10YR or 2.5Y dry or moist
Value: 6 or 7 dry; 3, 4 or 5 moist
Chroma: 1, 2 or 3 dry or moist
Texture: ashy coarse sandy loam or ashy loamy coarse sand
Clay content: 5 to 15 percent
Pumice paragravel content: 5 to 35 percent (poorly or well graded)
Volcanic glass content: 60 to 90 percent in the 0.02 to 2.0 mm fraction
Ammonium oxalate extractable Al plus 1/2 Fe: 0.2 to 0.4 percent
Phosphate retention: 10 to 25 percent
15 bar water content of air-dried samples: 6 to 10 percent
Organic matter content: 0.5 to 2 percent
Redoximorphic features: absent to many, fine to coarse iron masses; common or many, fine manganese nodules; absent to common, fine to coarse iron-manganese nodules
Reaction: moderately acid to neutral (pH 5.6 to 7.3)
BCc horizon
Depth to: 20 to 40 inches
Hue: 10YR or 2.5Y dry or moist
Value: 6, 7 or 8 dry; 4, 5, 6 or 7 moist
Chroma: 1, 2, 3 or 4 dry or moist
Texture: ashy coarse sand or ashy loamy coarse sand
Clay content:
Pumice paragravel content: 15 to 35 percent (poorly or well graded)
Volcanic glass content: 60 to 90 percent in the 0.02 to 2.0 mm fraction
Ammonium oxalate extractable Al plus 1/2 Fe: 0.4 to 1.0 percent
Phosphate retention: 25 to 35 percent
15 bar water content of air-dried samples: 6 to 10 percent
Organic matter content: 0 to 1 percent
Redoximorphic features: absent to many, fine to coarse iron masses; common or many, fine manganese nodules; absent to common, fine to coarse iron-manganese nodules
Reaction: moderately acid to neutral (pH 5.6 to 7.3)
COMPETING SERIES: These are the Chock, Tonata and Tutni series.
Chock soils have ashy loam or ashy sandy loam texture in the lower portion of the particle-size contol section.
Tonata soils have a mollic epipedon and silt loam fine earth textures.
Tutni soils are 14 to 20 inches deep to aquic conditions
GEOGRAPHIC SETTING:
Landscape - lava plateau
Landform - alluvial fans, drainageways, flood plains, and stream terraces
Elevation - 4525 to 5500 feet
Slope - 0 to 4 percent
Parent material - alluvium from Mt Mazama pumice
Climate - cold moist winters and cool dry summers
Mean annual air temperature - 41 to 45 degrees F
Mean January air temperature - 25 to 27 degrees F
Mean July air temperature - 57 to 60 degrees F
Mean annual precipitation - 18 to 36 inches
Frost-free period - 0 to 20 days
GEOGRAPHICALLY ASSOCIATED SOILS: These are Lapine and Wickiup soils. Lapine soils are on adjacent plateaus. They formed in volcanic ash and pumice, are excessively drained and have a xeric moisture regime. Wickiup soils are in nearby depressions. They are poorly drained and average greater than 35 percent pumice paragravel in the particle-size control section.
DRAINAGE AND PERMEABILITY:
Drainage - poorly drained
Permeability - rapid
Flooding - occasional to very frequent
Ponding - frequent
Water table - an apparent water table is at its uppermost limit form May to July
USE AND VEGETATION: Regcrust soils are used for wildlife habitat, watershed and recreation. The potential natural plant community is the grass-sedge-forb meadow plant association group (MDMW). The tufted hairgrass plant association (MM19-12), Baltic rush plant association (MW39-12) and widefruit sedge plant association (MM29-13) are commonly supported.
DISTRIBUTION AND EXTENT: Klamath County, Oregon; MLRA 6. Series is of small extent.
MLRA SOIL SURVEY REGIONAL OFFICE (MO) RESPONSIBLE: Portland, Oregon
SERIES PROPOSED: Winema National Forest, Klamath County, Oregon, 2001
REMARKS: Diagnostic horizons and features recognized in this pedon are:
Andic soil properties form 0 to 17 inches (the A1 and A2 horizons)
Particle-size control section from 0 to 40 inches (the A1, A2, Bwc and portion of the BCc horizons)
Aquic conditions, endosaturation on 16 September 1998 from 80 to 160 cm (portion of the Bwc2 horizon)
Aquic moisture regime
Cryic temperature regime
Umbric epipedon 0 to 17 inches
Contrast between the upper and lower portions of the particle-size control section does not meet criteria for a strongly contrasting particle-size class.
ADDITIONAL DATA: This pedon description is in NASIS pedon with Site ID 98-JFD-04 and NSSL S03OR-035-010.