LOCATION REGCRUST ORTentative Series
TAXONOMIC CLASS: Ashy, glassy, nonacid Vitrandic Cryorthents
TYPICAL PEDON: Regcrust supporting the lodgepole pine/kinnikinnick plant association on a 0 percent slope at 4554 feet. When described on 20 July 1999 the soil was moist to 135 inches and wet from 135 to 200 inches (colors are for dry soil unless otherwise noted).
Oi--0 to 1 inch; slightly decomposed plant material; forest litter of needles and twigs; abrupt smooth boundary. (0 to 1 inch thick)
Oa--1 to 2 inches; very dark brown (10YR 2/2) highly decomposed plant material, black moist; common fine and medium stems; forest litter of needles and twigs, 40 percent non-rubbed fiber, 10 percent rubbed fiber; moderately acid (pH 5.8); abrupt smooth boundary. (0 to 1 inch thick)
A--2 to 14 inches; light gray (10YR 7/2) paragravelly ashy loamy coarse sand, dark grayish brown (10YR 4/2) moist; weak fine granular structure; soft, friable, non-sticky and non-plastic; common very fine and fine roots, few medium and coarse roots; many very fine interstitial pores; 25 percent pmice paragravel; moderately acid (pH 5.8); diffuse smooth boundary. (2 to 16 inches thick)
E--14 to 51 inches; light gray (2.5Y 7/2) paragravelly ashy coarse sandy loam, grayish brown (10YR 5/2) moist; weak very coarse platy structure parting to weak fine platy; slightly hard, firm, non-sticky and non-plastic; many very fine interstitial pores and common fine tubular pores; 20 percent pumice paragravel; neutral (pH 6.8); gradual smooth boundary. (24 to 39 inches thick)
Eg--51 to 71 inches; pale yellow (2.5Y 8/2) very paragravelly ashy coarse sand, light olive brown (2.5Y 5/3) moist; single grain; loose, non-sticky and non-plastic; many very fine interstitial pores; 40 percent pumice paragravel; common fine prominent black (2.5Y 2.5/1) dry or moist manganese nodules in matrix; neutral (pH 7.2); gradual smooth boundary. (20 to 39 inches thick)
2Ab--71 to 79 inches; stratified brown (10YR 4/3) fine sand, dark brown (10YR 3/3) moist and light gray (2.5Y 7/2) ashy coarse sand, light olive brown (2.5Y 5/3) moist; single grain; loose, non-sticky and non-plastic; many very fine and fine interstitial pores; 5 percent pumice paragravel; common coarse prominent dark yellowish brown (10YR 4/6) iron masses in matrix, strong brown (7.5YR 4/6) moist; neutral (pH 6.6).
TYPE LOCATION: Klamath County, Oregon; about 15 miles south and 13 miles east of Chemult; about 370 feet north and 1540 feet east of the southwest corner of section 33, T. 29 S., R. 10 E. (Latitude 43 degrees, 00 minutes, 30 seconds North, Longitude 121 degrees, 32 minutes, 30 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 - 40 to 55 inches
Pumice paragravel content in the particle-size control section - averages less than 35 percent
Oi horizon
Thickness: 0 to 1 inch
Other: The horizon is discontinuous in shrub interspaces.
Oa horizon
Thickness: 0 to 1 inch
Hue, non-rubbed: 10YR dry or moist
Value, non-rubbed: 2 dry or moist
Chroma, non-rubbed: 2 dry, 1 moist
Non-rubbed fiber content: 40 to 50 percent
Rubbed fiber content: 10 to 17 percent
Reaction: strongly acid or moderately acid (pH 5.1 to 6.0)
Other: The horizon is discontinuous in shrub interspaces.
A horizon
Thickness: 2 to 16 inches
Hue: 10YR or 2.5Y dry or moist
Value: 4, 5, 6 or 7 dry; 2, 3 or 4 moist
Chroma: 1 or 2 dry or moist
Paragravel content: 15 to 30 percent pumice
Volcanic glass content: 60 to 100 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: 25 to 35 percent
Organic matter content: 0.5 to 2 percent
Reaction: strongly acid or moderately acid (pH 5.1 to 6.0)
E horizon
Depth to: 2 to 16 inches
Thickness: 24 to 39 inches
Hue: 10YR or 2.5Y dry or moist
Value: 6 or 7 dry, 4 or 5 moist
Chroma: 2 dry or moist
Texture: ashy coarse sandy loam or ashy loamy coarse sand
Sand content: 60 to 75 percent total sand, 25 to 30 percent coarse and very coarse sand
Paragravel content: 20 to 35 percent pumice
Volcanic glass content: 60 to 100 percent in the 0.02 to 2.0 mm fraction
Ammonium oxalate extractable Al plus 1/2 Fe: assume 0.2 to 0.4 percent
Phosphate retention: 10 to 25 percent
Organic matter content: 0.0 to 0.5 percent
Redoximorphic features: absent or few, fine iron masses; absent or few, fine manganese nodules
Reaction: slightly acid or neutral (pH 6.1 to 7.3)
Eg horizon
Depth to: 40 to 55 inches
Thickness: 20 to 39 inches
Hue: 10YR or 2.5Y dry or moist
Value: 6, 7 or 8 dry; 4, 5, 7 or 8 moist
Chroma: 1, 2 or 3 dry or moist
Texture: ashy loamy coarse sand or ashy coarse sand
Paragravel content: 20 to 60 percent pumice
Volcanic glass content: 60 to 100 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
Organic matter content: 0.0 to 0.5 percent
Redoximorphic features: absent to common, fine to coarse iron masses; common to many, fine manganese nodules; absent or few, fine to coarse iron-manganese nodules;
Reaction: slightly acid or neutral (pH 6.1 to 7.3)
2Ab horizon
Depth to: 59 to greater than 80 inches
Hue: 10YR or 2.5Y dry or moist
Value: 4, 5, 6 or 7 dry; 3, 4 or 5 moist
Chroma: 1, 2 or 3 dry or moist
Texture: stratified fine sand and pumice coarse sand
Paragravel content: 0 to 5 percent
Redoximorphic features: absent to many, fine to coarse iron masses
Reaction: neutral (pH 6.6 to 7.3)
COMPETING SERIES: There are no competing series.
GEOGRAPHIC SETTING:
Landscape - lava plateau
Landform - alluvial fans and drainageways
Elevation - 4525 to 5450 feet
Slope - 0 to 2 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 24 inches
Frost-free period - 5 to 35 days
GEOGRAPHICALLY ASSOCIATED SOILS: These are Lapine, Wickiup and Chocknott soils. Lapine soils are on adjacent lava 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, average greater than 35 percent pumice paragravel in the particle-size control section and have common or many redox accumulations within 5 inches of the mineral soil surface. Chocknott soils are on nearby alluvial fans, stream terraces and drainageways. They are poorly drained and have an umbric epipedon.
DRAINAGE AND PERMEABILITY:
Drainage - moderately well drained
Permeability - very rapid
Flooding - rare
Ponding - occasional
Water table - an apparent water table is at its uppermost limit form April to June
USE AND VEGETATION: Regcrust soils are used for timber production, wildlife habitat, watershed and recreation. The potential natural plant community is the lodgepole pine/kinnikinnick plant association (CLM2-11).
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:
Ochric epipedon
Redox concentrations - from 51 to 79 inches (the Eg and 2Ab horizons)
Lithologic discontinuity - 71 inches
Particle-size control section - from 12 to 42 (the A and portion of the Eg horizon)
Aquic conditions - endosaturation on 20 July 1999 from 53 to 79 inches (portion of the Eg and the 2Ab horizons)
Moisture regime - aquic
Temperature regime - cryic
Depth to diagnostic horizons and features are measured from the mineral soil surface.
ADDITIONAL DATA: The description is in NASIS pedon with Site ID 99-JFD-02. NSSL pedon id. S03OR-035-012.