LOCATION OZAMIS OREstablished Series
TAXONOMIC CLASS: Fine-loamy, mixed, superactive, mesic Fluvaquentic Endoaquolls
TYPICAL PEDON: Ozamis silty clay loam--meadow. (Colors are for moist soil unless otherwise noted.)
A--0 to 10 inches; black (10YR 2/1) silty clay loam, dark gray (N 4/0) dry; moderate thin platy structure parting to weak very fine granular; hard, firm, moderately sticky and moderately plastic; many very fine roots; few very fine tubular pores; moderately alkaline (pH 8.0); clear smooth boundary. (10 to 15 inches thick)
Cg1--10 to 20 inches; dark gray (10YR 4/1) silt loam, gray (N 6/0) dry; moderate very thin platy structure; hard, friable to firm, moderately sticky and slightly plastic; many very fine roots; few very fine tubular pores; many fine faint very dark gray (N 3/0) zones of iron depletion; slightly alkaline (pH 7.8); clear smooth boundary. (5 to 15 inches thick)
Cg2--20 to 34 inches; dark gray (10YR 4/1) silt loam, gray (N 6/0) dry; massive; slightly hard, friable, slightly sticky and slightly plastic; common very fine roots; few very fine tubular pores; common medium faint very dark gray (N 3/0) zones of iron depletion; neutral (pH 7.3); abrupt smooth boundary. (5 to 20 inches thick)
2C--34 to 36 inches; very pale brown (10YR 7/3) ashy coarse sand, white (N 8/0) dry; single grain; loose; very friable, nonsticky and nonplastic; few very fine roots; many very fine irregular pores; neutral (pH 7.3); abrupt smooth boundary. (0 to 4 inches thick)
3Cg3--36 to 60 inches; dark gray (10YR 4/1) very fine sandy loam, gray (10YR 5/1) dry; massive; slightly hard, very friable, slightly sticky and nonplastic; few very fine roots; few very fine tubular pores; many medium and fine faint very dark gray (N 3/0) zones of iron depletion; neutral (pH 7.3).
TYPE LOCATION: Lake County, Oregon; in Warner Valley about 2 miles southeast of Adel; about 50 feet south and 1,200 feet east of the northwest corner of section 26, T. 39 S., R. 24 E.; USGS Calderwood Reservoir 7.5 minute topographic quadrangle; 42 degrees 09 minutes 58 seconds north latitude and 119 degrees 51 minutes 41 seconds west longitude, NAD27.
RANGE IN CHARACTERISTICS:
Soil moisture - Usually saturated in some part of the moisture control section during spring and early summer unless drained, dry in all parts later in summer and fall unless irrigated; seasonal periods of aquic moisture regime between March and June during saturation with ground water and anaerobic conditions; an aridic moisture regime exists during the growing season in normal years after ground water levels drop below the moisture control section.
Mean annual soil temperature - 47 to 51 degrees F.
Mollic epipedon thickness - 10 to 15 inches.
Depth to 2C or 3C horizon - 30 to 50 inches.
Particle-size control section - Clay content: Averages 25 to 35 percent.
Reaction - Neutral through moderately alkaline.
Other features - Organic matter decreases irregularly with depth.
A horizon - Hue: 10YR through 5Y, or neutral (N).
Value: 2 through 4 dry.
Chroma: 0 (when hue is neutral) through 2, dry or moist.
Texture: Loam, silt loam, silty clay loam, or silty clay.
Organic matter content: 1 to 4 percent.
Cg1 and Cg2 horizons - Hue: 10YR through 5Y, or neutral (N).
Value: 5 through 8 dry, 4 through 6 moist.
Chroma: 0 (when hue is neutral) through 2, dry or moist.
Texture: Typically silt loam or silty clay loam but has strata of loam, clay loam, or silty clay.
Rock fragments: 0 to 10 percent gravel.
Redoximorphic features: Occurs as faint or distinct zones of iron depletion.
2C horizon (when present) - Value: 7 or 8 dry, 6 or 7 moist.
Volcanic glass content: 15 to 40 percent in coarse silt through coarse sand fractions.
3Cg horizon - Hue: 10YR through 5Y.
Value: 5 through 7 dry, 4 through 6 moist.
Chroma: 1 or 2, dry or moist.
Texture: Stratified sandy loam to silty clay loam.
Clay content: 10 to 30 percent.
COMPETING SERIES: These are Ambraw, Gansner, Settlemeyer, Sloan, and Toppenish series.
Ambraw and Sloan soils have peak periods of precipitation in the summer and do not have a volcanic ash influence. Gansner soils do not have a volcanic ash influence and formed in alluvium derived dominantly from metasedimentary rocks. Settlemeyer soils do not have a volcanic ash influence and may have a calcareous A horizon. Toppenish soils have very gravelly materials within the particle-size control section and have cambic horizons.
GEOGRAPHIC SETTING: Ozamis soils are on lakebeds and flood plains. These soils formed in stratified lacustrine deposits and alluvium derived from volcanic ash and volcanic rocks such as basalt and tuff. Slopes are 0 to 2 percent. Elevations range from 4,000 to 5,000 feet. The climate is semiarid and characterized by cool, wet winters and warm, dry summers. The mean annual precipitation is 6 to 14 inches, the mean annual temperature is 45 to 50 degrees F., and the frost-free period is 50 to 100 days.
GEOGRAPHICALLY ASSOCIATED SOILS: These are Crump, Drews, Kewake, Lakeview, and Reese soils. Crump soils have histic epipedons and are on slightly lower positions. Drews soils are well drained, have argillic horizons, and are on adjacent higher terraces. Kewake soils are on sand dunes. Lakeview soils are moderately well drained and have thick mollic epipedons. Reese soils have ochric epipedons and an SAR of 13 or more.
DRAINAGE AND PERMEABILITY: Poorly drained; medium or high surface runoff; moderately slow permeability. Endosaturation is present with an apparent seasonal high water table between the soil surface and 4 feet (shallow through deep free water occurrence classes) between March and June. Cumulative annual duration class is Common. A drained phase is recognized. Some phases are susceptible to frequent ponding for long duration from March through September with water up to 0.5 feet deep. Some phases of these soils are susceptible to rare flooding for very brief periods between March and September.
USE AND VEGETATION: Ozamis soils are used for native hay, pasture, and wildlife habitat. A few areas are used for annual grain. The principal native plants include alkali sacaton, alkali bluegrass, and inland saltgrass.
DISTRIBUTION AND EXTENT: South-central Oregon. These soils are moderately extensive. The series concept and main acreage is in MLRA 23, while other acreage occurs in MLRAs 21 and 24.
MLRA OFFICE RESPONSIBLE: Reno, Nevada.
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 10 inches (A horizon).
Aquic conditions - The conditions of endosaturation, reduction, and redoximorphic features between 10 and 60 inches at certain times during normal years (parts of the Cg1, Cg2, 2C, and 3Cg3 horizons).
Particle-size control section - The zone from 10 to 40 inches (Cg1, Cg2, and 2C horizons and part of the 3Cg3 horizon).