LOCATION TECOMAR                 NV

Established Series
Rev. STD-DWW-JVC-JBF
03/2012

TECOMAR SERIES

The Tecomar series consists of shallow, well drained soils that formed in residuum and colluvium derived from limestone and dolomite. Tecomar soils are on mountains and hills. Slopes are 8 to 50 percent. The mean annual precipitation is about 300 mm and the mean annual temperature is about 7 degrees C.

TAXONOMIC CLASS: Loamy-skeletal, carbonatic, mesic Lithic Xeric Haplocalcids

TYPICAL PEDON: Tecomar extremely stony silt loam--rangeland. (Colors are for dry soil unless otherwise noted.) The soil surface is partially covered with 25 percent gravel and 15 percent cobbles and stones.

A--0 to 5 cm; light gray (10YR 7/2) extremely stony silt loam, brown (10YR 5/3) moist; weak thick platy structure; slightly hard, very friable, moderately sticky and slightly plastic; common very fine and fine roots; few very fine tubular and many very fine interstitial pores; 30 percent gravel, 5 percent cobbles, and 30 percent stones; violently effervescent; moderately alkaline (pH 8.4); abrupt smooth boundary. (3 to 15 cm thick)

ABk--5 to 18 cm; pale brown (10YR 6/3) extremely cobbly silt loam, brown (10YR 5/3) moist; weak fine subangular blocky structure; slightly hard, very friable, moderately sticky and slightly plastic; many very fine and fine roots; few very fine tubular and many very fine interstitial pores; 40 percent gravel, 25 percent cobbles, and 10 percent stones; secondary calcium carbonates segregated as few coats on the bottom of rock fragments; violently effervescent; moderately alkaline (pH 8.4); clear smooth boundary. (0 to 20 cm thick)

Bk1--18 to 38 cm; pale brown (10YR 6/3) extremely cobbly silt loam, brown (10YR 5/3) moist; weak medium subangular blocky structure; slightly hard, very friable, moderately sticky and slightly plastic; many very fine, common fine, and few medium roots; common very fine tubular and many very fine interstitial pores; 40 percent gravel, 25 percent cobbles, and 10 percent stones; secondary calcium carbonates segregated as few coats around rock fragments and common pendants on bottoms of rock fragments; violently effervescent; strongly alkaline (pH 9.0) abrupt smooth boundary. (5 to 25 cm thick)

Bk2--38 to 48 cm; very pale brown (10YR 8/3) extremely cobbly silt loam, pale brown (10YR 6/3) moist; moderate medium subangular blocky structure; slightly hard, very friable, moderately sticky and slightly plastic; many very fine, and few fine and medium roots; common very fine tubular and many very fine interstitial pores; 40 percent gravel, 25 percent cobbles, and 10 percent stones; secondary calcium carbonates segregated as few coats around rock fragments and common pendants on bottoms of rock fragments; violently effervescent; strongly alkaline (pH 9.0); abrupt smooth boundary. (5 to 25 cm thick)

R--48 cm; limestone.

TYPE LOCATION: Elko County, Nevada; about 10 miles south-southwest of Montello in the north end of the Toano Range; about 500 feet east and 1,250 feet south of the northwest corner of section 34, T. 38 N., R. 68 E.; USGS Loray 7.5 minute topographic quadrangle; latitude 41 degrees 08 minutes 11 seconds N and longitude 114 degrees 16 minutes 19 seconds W; NAD 83.

RANGE IN CHARACTERISTICS:
Soil moisture: Usually dry, moist in winter and spring, dry June through October; aridic soil moisture regime that borders on xeric.
Mean annual soil temperature: 8 to 11 degrees C.
Depth to bedrock: 25 to 50 cm to a lithic contact.
Depth to calcic horizon: 5 to 36 cm.
Reaction: Moderately alkaline or strongly alkaline.
Calcium carbonate content: 40 to 60 percent in the less than 20 mm fraction.

Particle-size control section - Clay content: 20 to 27 percent.
Rock fragments: 50 to 80 percent. Lithology of fragments is limestone and dolomite.

A horizon
Value: 6 or 7 dry, 4 or 5 moist.
Chroma: 2 or 3, dry or moist.

Bk horizons
Value: 6 through 8 dry, 4 through 7 moist.
Chroma: 2 through 4, dry or moist.
Texture: Extremely cobbly silt loam, very cobbly silt loam, or extremely stony silt loam.
Structure: Subangular blocky or massive.
Consistence: Soft or slightly hard dry, slightly sticky to moderately sticky, moist; slightly plastic to moderately plastic.
Calcium carbonate equivalent: 20 to 40 percent.

COMPETING SERIES: These are the Amtoft and Pookaloo series.

Amtoft soils have 12 to 20 percent clay and dominantly loam or fine sandy loam texture in the particle-size control section. Pookaloo soils have 10 to 18 percent clay and 35 to 50 percent gravel in the particle-size control section.

GEOGRAPHIC SETTING: Tecomar soils are on mountains and hills. They typically occur on shoulders and backslopes. These soils formed in residuum and colluvium derived from limestone and dolomite. Slopes are 8 to 50 percent. Elevations range from 1,650 to 2,570 meters. The climate is semiarid with cool, moist winters and warm, dry summers. The mean annual precipitation is 250 to 400 mm, mean annual temperature is 7 to 10 degrees C, and the frost-free period is 90 to 110 days.

GEOGRAPHICALLY ASSOCIATED SOILS: These are the Hopeka, Kram, and Kzin soils. These soils are all shallow or very shallow to bedrock.

DRAINAGE AND SATURATED HYDRAULIC CONDUCTIVITY: Well drained; very high surface runoff; moderately high saturated hydraulic conductivity.

USE AND VEGETATION: Tecomar soils are used for livestock grazing and wildlife habitat. The present vegetation is mainly black sagebrush, bluebunch wheatgrass, and Sandberg's bluegrass.

DISTRIBUTION AND EXTENT: Eastern Nevada. These soils are extensive with about 199,000 acres of the series mapped to date. The series concept is in MLRA 28A, while the main acreage occurs in MLRAs 25 and 28B.

MLRA SOIL SURVEY REGIONAL OFFICE (MO) RESPONSIBLE: Phoenix, Arizona.

SERIES ESTABLISHED: Elko County (Northeast Part), Nevada, 1986.

REMARKS: Diagnostic horizons and features recognized in this pedon are:
Ochric epipedon - The zone from the soil surface to 18 cm (A and ABk horizons).
Calcic horizon - The zone from 18 to 48 cm (Bk1 and Bk2 horizons).
Lithic contact - The boundary at 48 cm to underlying hard bedrock (R layer).
Particle size control section - The zone from 25 to 48 cm (Bk2 horizon and part of the Bk1 horizon).

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National Cooperative Soil Survey
U.S.A.