LOCATION CRESSLER OREstablished Series
TAXONOMIC CLASS: Fine, smectitic, frigid Fluvaquentic Endoaquolls
TYPICAL PEDON: Cressler silty clay loam--in a meadow on a 1 percent slope--rangeland. (Colors are for moist soil unless otherwise noted.)
A--0 to 6 inches; very dark grayish brown (10YR 3/2) silty clay loam, dark grayish brown (10YR 4/2) dry; moderate fine and medium granular structure; hard, friable, sticky and plastic; many roots; many very fine irregular pores; moderately acid (pH 5.8); abrupt smooth boundary. (4 to 10 inches thick)
Bt1--6 to 15 inches; very dark brown (10YR 2/2) silty clay, dark gray (10YR 4/1) dry; weak fine prismatic structure parting to strong angular blocky structure; very hard, very firm, very sticky and very plastic; common roots; common very fine and fine tubular pores; common faint clay films on faces of peds; slightly acid (pH 6.2); clear smooth boundary. (7 to 11 inches thick)
Bt2--15 to 38 inches; grayish brown (10YR 5/2) silty clay, light brownish gray (10YR 6/2) dry; moderate medium prismatic structure; very hard, very firm, very sticky and very plastic; few roots; common fine tubular pores; common distinct clay films on faces of peds and lining pores; few fine prominent yellowish brown (10YR 5/6) masses of iron accumulation; neutral (pH 6.6); gradual wavy boundary. (19 to 27 inches thick)
BC--38 to 48 inches; brown (10YR 5/3) clay loam, light brownish gray (10YR 6/2) dry; massive; hard, firm, very sticky and plastic; few roots; common very fine and fine tubular pores; many fine distinct yellowish brown (10YR 5/6) masses of iron accumulation; neutral (pH 6.7); clear smooth boundary. (8 to 11 inches thick)
C--48 to 60 inches; brown (10YR 5/3) extremely stony clay, brown (10YR 5/3) dry; massive; hard, firm, very sticky and very plastic; few roots; 15 percent stones, 35 percent cobbles, and 25 percent pebbles; many fine distinct yellowish brown (10YR 5/6) masses of iron accumulation; slightly acid (pH 6.4).
TYPE LOCATION: Lake County, Oregon; on the Fremont National Forest about 9 miles east-southeast of Lakeview near Horse Creek; in the SE 1/4 of the NE 1/4 of section 25, T. 39 S., R. 21 E.; USGS Horse Prairie 7.5 minute topographic quadrangle.
RANGE IN CHARACTERISTICS:
Soil moisture - Usually moist in the upper three feet in winter and spring, dry from late July through mid-October; a seasonal high water table is present from the soil surface to 3 feet from December through June; aquic moisture regime.
Mean annual soil temperature - 45 to 47 degrees F.
Mollic epipedon thickness - 10 to 20 inches, includes the Bt1 horizon.
Particle-size control section - Clay content: 35 to 50 percent; Rock fragments: averages 0 to 15 percent, mainly pebbles. Lithology of fragments is basalt.
Redoximorphic features - Distinct and/or prominent redox concentrations of iron are present and occur within 10 to 20 inches of the soil surface. Some pedons which are more moist have redox concentrations in the lower part of the mollic epipedon.
A horizon - Hue: 10YR or 7.5YR.
Value: 2 or 3 moist, 3 or 4 dry.
Chroma: 1 or 2, moist or dry.
Clay content: 30 to 40 percent.
Organic matter content: 5 to 8 percent.
Bt1 horizon - Hue: 10YR or 7.5YR.
Value: 2 through 5 moist, 4 or 5 dry.
Chroma: 1 or 2, moist or dry.
Texture: Silty clay, clay, or clay loam.
Clay content: 35 to 45 percent.
Rock fragments: 0 to 15 percent pebbles.
Reaction: Slightly acid or neutral.
Organic matter content: 1 to 5 percent.
Other features: Clay increase is not enough to meet required characteristic for the argillic horizon.
Bt2 horizon - Hue: 10YR or 7.5YR.
Value: 2 through 5 moist, 4 or 5 dry.
Chroma: 1 or 2, moist or dry.
Texture: Silty clay, clay, or clay loam.
Clay content: 35 to 45 percent.
Rock fragments: 0 to 15 percent pebbles.
Reaction: Slightly acid or neutral.
BC horizon - Hue: 10YR or 7.5YR.
Value: 4 or 5 moist, 5 or 6 dry.
Chroma: 2 through 4, moist or dry.
Texture: Clay loam or clay.
Clay content: 35 to 50 percent.
Rock fragments: 0 to 15 percent pebbles.
Reaction: Slightly acid or neutral.
C horizon (when present) - Hue: 10YR or 7.5YR.
Value: 4 or 5 moist, 5 or 6 dry.
Chroma: 2 through 4, moist or dry.
Clay content: 40 to 50 percent.
Rock fragments: Total range is 60 to 85 percent, with 35 to 65 percent cobbles and stones, 15 to 30 percent pebbles.
Reaction: Slightly acid or neutral.
COMPETING SERIES: At present, there are no other series in this family.
GEOGRAPHIC SETTING: Cressler soils are on upland basins. These soils formed in alluvium derived from basalt. Slopes are 0 to 2 percent. Elevations range from 5,500 to 6,800 feet. The climate is characterized by cold, moist winters and cool, dry summers. The mean annual precipitation is 22 to 26 inches. The mean annual temperature is 43 to 45 degrees F. The frost-free period is 30 to 50 days.
GEOGRAPHICALLY ASSOCIATED SOILS: These are the Degarmo and Welch soils. Degarmo and Welch soils have a mollic epipedon over 24 inches thick. Degarmo soils are fine-loamy over sandy or sandy-skeletal. Welch soils are fine-loamy.
DRAINAGE AND PERMEABILITY: Somewhat poorly drained; negligible or low surface runoff; slow permeability in the substratum. These soils are frequently ponded for long duration from December through June with water up to 0.5 feet deep.
USE AND VEGETATION: Cressler soils are used for livestock grazing and wildlife habitat. The vegetation is mainly tufted hairgrass, sedge, and rushes. The rangeland ecological site is Wet meadow, 021XY406OR.
DISTRIBUTION AND EXTENT: Southcentral Oregon. These soils are not extensive with about 3,600 acres of the series mapped to date. MLRA 21.
MLRA SOIL SURVEY REGIONAL OFFICE (MO) RESPONSIBLE: Davis, California.
SERIES ESTABLISHED: Lake County (Southern Part), Oregon, 1991.
REMARKS: Diagnostic horizons and features recognized in this pedon are:
Mollic epipedon - The zone from the soil surface to 15 inches (A and Bt1 horizons).
Cambic horizon - The zone from 15 to 38 inches (Bt2 horizon).
Fluventic feature - The zone from the soil surface to 50 inches with 0.3 percent or more organic-carbon content (A, Bt1, Bt2, and BC horizons and part of the C horizon) or the zone from 38 to 50 inches with an irregular decrease in organic-carbon content (BC and C horizons).
Aquic conditions - Endosaturation and iron reduction occur within 20 inches of the soil surface in most years.
Particle-size control section - The zone from 10 to 40 inches (Bt2 horizon and parts of the Bt1 and BC horizons).