LOCATION OBANION                 NV

Established Series
WMA/ELS/JBF
06/2017

OBANION SERIES

The Obanion series consists of very deep, very poorly drained soils formed in alluvium and lacustrine sediments. These soils are on alluvial fans and basin fill plains. Slopes are 0 to 2 percent. The mean annual temperature is about 11 degrees C. and the mean annual precipitation is about 200 mm.

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

TYPICAL PEDON: Obanion loamy coarse sand - wet meadow. (Colors are for moist soil unless otherwise noted.)

A1--0 to 18 cm; grayish brown (10YR 5/2) loamy coarse sand, grayish brown (10YR 5/2) dry; single grained; loose; many very fine roots, with 1.5 cm root mat on surface; common very fine tubular and many very fine interstitial pores; slightly alkaline (pH 7.8); abrupt wavy boundary. (5 to 25 cm thick)

A2--18 to 28 cm; very dark grayish brown (10YR 3/2) coarse sandy loam, many medium and coarse distinct dark reddish brown (5YR 3/4) iron mottles, gray (5Y 6/1) dry; massive; hard, friable, nonsticky and nonplastic; many very fine roots in pockets; common very fine interstitial pores; strongly alkaline (pH 8.6); clear smooth boundary. (5 to 15 cm thick)

C--28 to 38 cm; brown (10YR 4/3) sandy clay loam, few medium and coarse distinct dark reddish brown (5YR 3/4) iron mottles and few very coarse prominent dark greenish gray (5G 4/1) gleyed colors, dark gray (5Y 4/1) and light gray (5Y 7/1) dry; massive; very hard, firm, moderately sticky and moderately plastic; common very fine roots; common very fine interstitial pores; very strongly alkaline (pH 9.2); clear smooth boundary. (13 to 23 cm thick)

Cg--38 to 56 cm; dark greenish gray (5G 4/1) and light yellowish brown (2.5Y 6/4) sandy clay loam, light greenish gray (5GY 7/1) dry; massive; very hard, firm, moderately sticky and moderately plastic; few very fine roots; 15 percent 1.5 cm firm durinodes; strongly effervescent; very strongly alkaline (pH 9.2); abrupt wavy boundary. (13 to 23 cm thick)

C'--56 to 86 cm; light olive brown (2.5Y 5/4) sandy loam, light gray (5Y 7/1) dry; massive; slightly hard, friable, slightly sticky and slightly plastic; very few very fine roots; strongly effervescent; strongly alkaline (pH 8.5); abrupt wavy boundary. (25 to 40 cm thick)

Ck--86 to 152 cm; dark olive gray (5Y 3/2) sandy loam, many medium and coarse distinct olive (5Y 5/4) iron mottles and many medium and coarse prominent pink (5YR 7/3) soft carbonate masses, gray (5Y 6/1) dry; massive; slightly hard, friable, slightly sticky and slightly plastic; 15 percent 1.5 cm durinodes; strongly effervescent; very strongly alkaline (pH 9.8).

TYPE LOCATION: Lyon County, Nevada; in Smith Valley; about 500 feet south and 500 feet west of the northeast corner of section 15, T. 11 N., R. 23 E.; USGS Oreana Peak 7.5 minute topographic quadrangle; latitude 38 degrees 49 minutes 20 seconds N and longitude 119 degrees 23 minutes 12 seconds W; WGS84 Decimal Degrees 38.8222222 latitude, -119.3866667 longitude.

RANGE IN CHARACTERISTICS:
Soil moisture: Usually saturated in the late winter and spring unless drained.
Mean annual soil temperature: 53 or 54 degrees F.
Exchangeable sodium: 15 to 35 percent in more than half of the upper 50 cm and decreases with depth.
Effervescence: Noncalcareous to strongly effervescent in any horizon but pedons are noncalcareous in some part between 25 and 50 cm.

Particle-size control section - Clay content: 18 to 35 percent.

A horizons
Value: 4 through 6 dry and 3 through 5 moist, lacks the combination of values or the thickness for a mollic epipedon.
Chroma: 1or 2.

C horizons
Hue: 10YR, 2.5Y, 5Y, 5GY, or 5G. Value: 3 through 5 moist and 4 through 7 dry.
Chroma: 1 through 4.
Texture: Average loam or sandy clay loam, strata of loam, clay loam, and sandy loam are most common but loamy sand or sand are in some pedons.

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

GEOGRAPHIC SETTING: Obanion soils are in depressions and seep areas on alluvial fans and basin fill plains. Elevations are 1,370 to 1,524 meters. They have formed in mixed alluvium or lacustrine sediments. Slopes are 0 to 2 percent. The climate is arid. The mean annual temperature is 10 to 11 degrees C.; average annual precipitation of 150 to 230 mm; and the frost free season is l00 to l30 days.

GEOGRAPHICALLY ASSOCIATED SOILS: These are the Saralegui, Wedertz, and Wellington soils. None of these have water tables. Also Wedertz and Wellington soils have an argillic horizon and a Bqk horizon or duripan. Saralegui soils have an argillic horizon.

DRAINAGE AND SATURATED HYDRAULIC CONDUCTIVITY: Very poorly drained; the water table is at 15 to 50 cm during the late winter and spring, and fluctuates between 50 and 100 cm during the rest of the year. The water table level is largely related to the artesian pressure. Very slow or ponded runoff; moderately slow permeability; moderately high saturated hydraulic conductivity.

USE AND VEGETATION: Obanion soils are used for native and wet meadow pasture. Some are used for water fowl habitat. The vegetation is principally saltgrass, sedges, and wiregrass.

DISTRIBUTION AND EXTENT: Valleys in western Nevada. They are of limited extent. MLRA 26.

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

SERIES ESTABLISHED: Lyon County Area, Nevada, 1981.

REMARKS: Diagnostic horizons and features recognized in this pedon are:
Ochric epipedon: From the surface to 18 cm (A1 horizon)
Zone of endosaturation: From 18 cm to 152 cm (A2, C, Cg, C' and Ck horizons).
Particle-size control section - The zone from 25 to 100 cm. (C, Cg, C' and part of A2 and Ck horizons).

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National Cooperative Soil Survey
U.S.A.