LOCATION ORIZABA                 NV

Established Series
Rev. DMC/ELS/RLB/JBF
05/2016

ORIZABA SERIES

The Orizaba series consists of very deep, somewhat poorly drained soils that formed in alluvium derived from mixed rocks. The Orizaba soils are on alluvial flats, lake plains, floodplains and beach plains. Slopes are 0 to 2 percent The mean annual precipitation is about 150 mm and the mean annual temperature is about 9 degrees C.

TAXONOMIC CLASS: Fine-loamy, mixed, superactive, calcareous, mesic Aeric Halaquepts

TYPICAL PEDON: Orizaba loam--rangeland (Colors are for dry soil unless otherwise noted.)

A1--0 to 8 cm; light gray (10YR 7/2) loam, olive (5Y 4/3) moist; massive; slightly hard, very friable, slightly sticky and slightly plastic; few very fine, and fine roots; many very fine vesicular pores, and few very fine tubular pores; violently effervescent; very strongly alkaline (pH 9.6); abrupt smooth boundary. (8 to 25 cm thick)

A2--8 to 23 cm; gray (10YR 6/1) silty clay loam, dark grayish brown (10YR 4/2) moist; black (10YR 2/1) coatings on fracture planes; massive; slightly hard, very friable, moderately sticky and moderately plastic; many very fine and few fine and medium roots; few very fine and fine tubular pores; violently effervescent; very strongly alkaline (pH 9.6); abrupt smooth boundary. (15 to 36 cm thick)

C1--23 to 43 cm; gray (5Y 6/1) silty clay loam, olive (5Y 4/3) moist; massive; hard, very friable, moderately sticky and moderately plastic; few very fine roots; common very fine tubular pores; violently effervescent; very strongly alkaline (pH 9.6); abrupt wavy boundary. (15 to 46 cm thick)

C2--43 to 58 cm; gray (10YR 6/1) sand, dark grayish brown (10YR 4/2) moist; massive; slightly hard, very friable, nonsticky and nonplastic; few very fine roots; few very fine tubular pores; strongly alkaline (pH 8.8); clear smooth boundary. (0 to 25 cm thick)

Ck--58 to 152 cm; light gray (10YR 7/2) stratified loam and silty clay loam, brown (10YR 5/3) moist; common large mottles, black (10YR 2/1) moist; massive; slightly hard, very friable, moderately sticky and moderately plastic; few very fine roots; few very fine tubular pores; common white (10YR 8/1) lime coating pores; violently effervescent; strongly alkaline. (pH 8.6)

TYPE LOCATION: Nye County, Nevada; 1,000 feet west of the E1/4 corner of sec 21, T 11 N, R 43 E; USGS Carvers, NV 7.5 minute topographic quadrangle; latitude 38 degrees 47 minutes 54 seconds N and longitude 117 degrees 8 minutes 55 seconds W; WGS84 Decimal Degrees 38.7984444 latitude, -117.1486111 longitude.

RANGE IN CHARACTERISTICS:
Soil moisture: Usually moist, moist in all parts of the moisture control section during the winter and spring dry summer and late fall; typic aridic soil moisture regime.
Mean annual soil temperature: 10 to 13 degrees C.
Reaction: Moderately alkaline through very strongly alkaline.
Electrical conductivity: 8 to 20 mmhos in the A horizon and upper part of the 25 to 100 cm particle-size control section.
Exchangeable sodium: 15 to 40 percent.

Particle-size control section - Clay content: Averages 28 to 35 percent.

A horizon
Hue 10YR or 5YR
Value: 6 or 7 dry, 4 or 5 moist.
Chroma: 1 through 3.

C and Ck horizons
Hue 10YR, 2.5Y or 5Y
Value: 5 through 8 dry, 4 through 6 moist.
Chroma: 1 through 3.
Texture: Silty clay loam or clay loam and have thin strata of loam, sandy loam or sand
Structure: Massive but have week or moderate, fine and medium subangular or platy structure in some pedons.
Other features: Few or common segregated soft seams or filaments and concretions of lime are in some pedons Less than 20 percent durinodes or a horizon less than 15 cm thick containing durinodes are within 60 cm in some pedons.

COMPETING SERIES: There are no other series in this family.

GEOGRAPHIC SETTING: Orizaba soils are on alluvial flats, lake plains, floodplains and terraces at elevations of 1,400 to 1,700 meters. Slopes are less than 1 percent. These soils formed in alluvium derived from mixed rocks Mean annual precipitation is 100 to 250 mm. Mean annual temperature is 8 to 11 degrees C and the frost-free season is 100 to 120 days.

GEOGRAPHICALLY ASSOCIATED SOILS: These are the Charnock, Fivemile and Lahontan soils. Charnock soils have 18 to 27 percent clay in the particle-size control section. Fivemile soils have fine silty particle-size control sections and are not saturated within a depth of 150 cm. Lahontan soils have fine textured particle-size control sections.

DRAINAGE AND SATURATED HYDRAULIC CONDUCTIVITY: Somewhat poorly and poorly drained; slow runoff; moderately high saturated hydraulic conductivity. Some flooding occurs in the spring and during high intensity summer storms. Depth to the water table ranges from 76 to 150 cm.

USE AND VEGETATION: Rangeland. The vegetation is principally big rabbitbrush, black greasewood, big sagebrush, saltgrass, giant wildrye and alkali sacaton.

DISTRIBUTION AND EXTENT: Central and Western Nevada. These soils are inextensive. MLRA 29.

MLRA SOIL SURVEY REGIONAL OFFICE (MO) RESPONSIBLE: Davis, California

SERIES ESTABLISHED: Nye County (Big Smoky Valley Area), Nevada, 1972.

REMARKS: Diagnostic horizons and features recognized in this pedon are:
Ochric epipedon - The zone from the soil surface to 18 cm. (A1 and part of the A2 horizons).
Aeric feature - chroma of 3 in some subhorizon within 76 cm.
Particle-size control section - The zone from 25 to 100 cm. (C1, C2, and part of C3 horizon).

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National Cooperative Soil Survey
U.S.A.