LOCATION TOMERA                  NV

Established Series
Rev: RAF/GJS/JBF
12/2019

TOMERA SERIES

The Tomera series consists of very deep, well drained soils that formed in alluvium derived from mixed, but dominantly sedimentary rocks and pyroclastic materials. Tomera soils are on dissected terraces and alluvial fans. Slopes are 2 to 15 percent. The mean annual precipitation is about 230 mm and the mean annual temperature is about 8 degrees C.

TAXONOMIC CLASS: Fine, smectitic, mesic Xeric Natrargids

TYPICAL PEDON: Tomera silt loam - rangeland. (Colors are for dry conditions unless otherwise noted.)

A1--0 to 8 cm; light brownish gray (10YR 6/2) silt loam, dark grayish brown (10YR 4/2) moist; weak medium platy structure; slightly hard, friable, slightly sticky and slightly plastic; many fine roots; many fine vesicular pores; 5 percent gravel; neutral (pH 7.0); clear smooth boundary. (3 to 13 cm thick)

A2--8 to 23 cm; light brownish gray (10YR 6/2) silt loam, dark grayish brown (10YR 4/2) moist; weak thick platy structure; slightly hard, friable, slightly sticky and slightly plastic; many fine roots; common fine vesicular pores; 5 percent gravel; neutral (pH 7.0); clear smooth boundary. (0 to 15 cm thick)

Bt--23 to 51 cm; light brownish gray (10YR 6/2) gravelly clay, brown (10YR 4/3) moist; weak medium prismatic structure; hard, firm, very sticky and very plastic; many fine roots; many very fine exped tubular pores; many faint clay films on peds and in pores; l5 percent gravel; slightly alkaline (pH 7.4); gradual smooth boundary. (13 to 30 cm thick)

Btn--51 to 66 cm; brown (10YR 5/3) gravelly clay, brown (10YR 4/3) moist; weak medium prismatic structure; hard, firm, very sticky and very plastic; many very fine roots; many very fine exped tubular pores; many faint clay films on peds and in pores; 25 percent gravel; moderately alkaline (pH 8.4); clear wavy boundary. (0 to 25 cm thick)

Btnk1--66 to 86 cm; brown (10YR 5/3) clay, brown (10YR 5/3) moist, weak medium and fine subangular blocky structure; hard, friable, very sticky and very plastic; many very fine roots; many very fine exped tubular pores; common faint clay films on peds and in pores; 10 percent gravel; slightly effervescent, strongly effervescent in common fine pale brown (10YR 6/3) soft masses of carbonates; strongly alkaline (pH 8.8); clear wavy boundary. (15 to 36 cm thick)

Btnk2--86 to 99 cm; pale brown (10YR 6/3) gravelly sandy clay loam, brown (10YR 4/3) moist, weak fine subangular blocky structure; hard, friable, moderately sticky and moderately plastic; few very fine roots; few very fine tubular pores; many faint clay films on peds and in pores; 20 percent gravel; strongly effervescent; common fine pale brown (10YR 6/3) soft masses of carbonates; strongly alkaline (pH 8.9); abrupt smooth boundary. (0 to 25 cm thick)

2C--99 to 152 cm; light gray (10YR 7/2) extremely gravelly sandy loam, brown (10YR 5/3) moist; massive; slightly hard, very friable, nonsticky and nonplastic; few very fine roots; many very fine interstitial pores; 70 percent gravel and 2 percent cobbles; strongly effervescent; strongly alkaline (pH 9.0).

TYPE LOCATION: Eureka County, Nevada. Approximately 500 feet east of the west one-fourth corner of Section 9, T. 30 N., R. 5l E.; USGS McCormack Spring 7.5 minute topographic quadrangle. About 4 miles south of the Iron Blossom mine; latitude 40 degrees 29 minutes 4 seconds N and longitude 116 degrees 14 minutes 48 seconds W; WGS84 Decimal Degrees 40.4844444 latitude, -116.2466667 longitude.

RANGE IN CHARACTERISTICS:
Soil moisture: Moist in winter and spring; dry mid June through October; aridic soil moisture regime bordering on xeric.
Mean annual soil temperature: 8 to 10 degrees C.
Depth to carbonate: 38 to 76 cm.
Depth to base of Btnk horizon: 76 to 107 cm.
Reaction: Neutral through strongly alkaline increasing with depth.
Other features: Some pedons may have thin clay loam AB horizons above the Bt horizon.

Particle-size control section - Clay content: 40 to 60 percent.
Rock fragments: Average 10 to 30 percent.

A horizon
Hue: 10YR or 2.5Y.
Value: 6 or 7 dry, 3 or 4 moist.
Chroma: 2 through 3.
Structure: Weak or moderate thin to thick platy.

Bt, Btn and Btnk horizons
Hue: 10YR or 7.5YR.
Value: 5 or 6 dry, 4 or 5 moist.
Chroma: 2 through 4.
Texture: Clay, gravelly clay, sandy clay or gravelly sandy clay in the upper 50 cm; the lower part may be clay loam, gravelly clay loam, sandy clay loam or gravelly light sandy clay.
Structure: Upper part-weak or moderate fine or medium prismatic; lower part prismatic or weak or moderate fine or medium subangular or angular blocky.
Reaction: Neutral through moderately alkaline in the upper part increasing to moderately alkaline or strongly alkaline in the lower part.
Other features: Nonsaline or slightly saline.
Exchangeable sodium: 1 to 10 percent in the upper subhorizon and 15 to 30 percent in the lower subhorizon.

2C, 2Bk horizon
Value: 6 or 7 dry, 4 or 5 moist.
Chroma: 2 through 4.
Texture: Very gravelly loamy sand, extremely gravelly sandy loam or very cobbly loam.
Rock fragments: 5 to 25 percent cobbles, 25 to 70 percent gravel.

COMPETING SERIES: These are the Chappuis, Kiesel, Longdis, Owinza and Standish series.

Chappuis soils have carbonates starting at 8 to 38 cm. Kiesel soils are calcareous throughout. Longdis soils lack rock fragments in the particle-size control section. Owinza soils are calcareous in the Btn horizons. Standish soils are somewhat poorly drained.

GEOGRAPHIC SETTING: Tomera soils are on dissected terraces and alluvial fans. These soils formed in alluvium derived from mixed but dominantly sedimentary rocks and pyroclastic materials. Slopes are 2 to 15 percent. Elevations are 1,460 to 1,830 meters. The climate is cool, semiarid with cool, moist winters and warm, dry summers. The mean annual precipitation is 200 to 250 mm; mean annual temperature is 7 to 8 degrees C., and the frost free season is 100 to 120 days.

GEOGRAPHICALLY ASSOCIATED SOILS: These are the Cherry Spring, Chiara, Cortez, and Orovada soils. Cherry Spring and Cortez soils have duripans at depths between 50 and 100 cm. Chiara soils have a duripan at depths of less than 50 cm. Orovada soils have a cambic horizon and have a coarse-loamy particle-size control section.

DRAINAGE AND SATURATED HYDRAULIC CONDUCTIVITY: Well-drained; medium runoff; moderately low saturated hydraulic conductivity.

USE AND VEGETATION: Livestock grazing and wildlife habitat. Vegetation is mainly big sagebrush, Sandberg bluegrass, cheatgrass and annual forbs.

DISTRIBUTION AND EXTENT: North-central Nevada. Tomera soils are of moderately extensive. MLRA 25.

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

SERIES ESTABLISHED: Eureka County, (Tuscarora Mountain Area), Nevada, l979.

REMARKS: Diagnostic horizons and features recognized in this pedon are:
Ochric epipedon - The zone from the soil surface to 23 cm (A1 and A2 horizons).
Argillic horizon - The zone from 23 to 99 cm (the Bt, Btn, Btnk1 and Btnk2 horizons).
Natric horizon - The zone from 50 to 99 cm (the Btn, Btnk1 and Btnk2 horizons).
Particle-size control section - The zone from about 23 to 73 cm (the Bt and Btn horizons and part of the Btnk1 horizon).

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National Cooperative Soil Survey
U.S.A.