LOCATION BLACK BUTTE             NV

Established Series
Rev. DJM/JC/ET
04/2015

BLACK BUTTE SERIES

The Black Butte series consists of very deep, moderately well drained soils that formed in mixed over bank deposits derived from mixed rock sources. Black Butte soils are on floodplains. Slopes are from 0 to 2 percent. The mean annual precipitation is about 5 inches. The mean annual temperature is about 68 degrees F.

TAXONOMIC CLASS: Fine-silty over sandy or sandy-skeletal, aniso, mixed, active, thermic Typic Haplosalids

TYPICAL PEDON: Black Butte loam - rangeland. (Colors are for dry soil unless otherwise noted.) The soil surface is covered with 1 to 10 percent efflorescent salt crust.

Az1--0 to 2 inches; brown (7.5YR 5/4) loam, brown (7.5YR 4/4) moist; strong very thick platy structure hard, firm, slightly sticky, moderately plastic; few very fine roots; common fine interstitial and few very fine and fine vesicular pores; slightly effervescent; strongly alkaline (pH 9.0); clear smooth boundary. (1 to 3 inches thick)

Az2--2 to 8 inches; brown (7.5YR 5/4) stratified silty clay loam to very fine sandy loam, brown (7.5YR 4/4) moist; moderate fine subangular blocky structure hard, firm, moderately sticky, very plastic; common medium roots and few coarse roots; common fine interstitial pores; 15 percent fine faint irregular very weakly cemented salt masses with clear boundaries in matrix; violently effervescent; strongly alkaline (pH 8.6); clear smooth boundary. (4 to 8 inches thick)

Byz--8 to 13 inches; brown (7.5YR 5/4) stratified silty clay loam to very fine sandy loam, brown (7.5YR 4/4) moist; moderate fine angular blocky structure hard, firm, moderately sticky, very plastic; common medium roots and few coarse roots; common fine interstitial and few fine and medium tubular pores; 8 percent fine distinct spherical weakly cemented gypsum masses with clear boundaries in matrix; violent effervescence; strongly alkaline, pH 8.6; abrupt wavy boundary. (5 to 10 inches thick)

2Byz1--13 to 24 inches; light brown (7.5YR 6/4) loamy fine sand, brown (7.5YR 5/4) moist; 5 percent coarse distinct dark brown (7.5YR 3/3) and 15 percent coarse prominent yellowish red (5YR 5/8) mottles; massive soft, very friable, nonsticky, nonplastic; common medium roots and common very fine roots; many fine interstitial pores; 4 percent medium distinct spherical very weakly cemented gypsum masses with clear boundaries in matrix; strongly effervescent; moderately alkaline (pH 8.4); clear wavy boundary. (8 to 12 inches thick)

2Byz2--24 to 33 inches; loamy very fine sand, brown (7.5YR 5/4) moist; 4 percent coarse prominent yellowish red (5YR 5/8) mottles; massive soft, very friable, nonsticky, nonplastic; few fine roots and common very fine roots; many very fine tubular and many very fine interstitial pores; strongly effervescent; moderately alkaline (pH 8.4); clear smooth boundary. (8 to 10 inches thick)

2Byz3--33 to 39 inches; brown (7.5YR 5/4) very fine sandy loam, brown (7.5YR 4/4) moist; 15 percent coarse prominent yellowish red (5YR 5/8) mottles; massive soft, very friable, slightly sticky, nonplastic; common fine roots; few fine tubular and common very fine interstitial pores; 8 percent fine distinct spherical weakly cemented gypsum masses with clear boundaries in matrix; strongly effervescent; strongly alkaline (pH 8.6); abrupt wavy boundary. (0 to 12 inches thick)

3C1--39 to 57 inches; pink (7.5YR 7/4) stratified sand and very gravelly sand, brown (7.5YR 5/4) moist; 1 percent fine prominent reddish yellow (7.5YR 6/8) mottles; single grain loose, loose, nonsticky, nonplastic; common fine roots and common very fine roots; many fine interstitial pores; strongly effervescent; strongly alkaline (pH 8.6); abrupt smooth boundary. (15 to 25 inches thick)

3C2--57 to 67 inches; light brown (7.5YR 6/4) loamy fine sand, reddish brown (5YR 5/4) moist; 5 percent medium distinct yellowish red (5YR 4/6) mottles; massive; soft, very friable, nonsticky, nonplastic; few very fine and fine roots; few very fine tubular and common very fine interstitial pores; strongly effervescent; strongly alkaline (pH 8.6)

TYPE LOCATION: Northeastern Clark County, Nevada; approximately 5.2 miles downstream from the Riverside Bridge along the Virgin River next to a pole line road; 2,603 feet east and 302 feet north of the southwest corner of section 28, T. 14 S., R. 69 E.; USGS Overton N.E., 7.5 minute topographic quadrangle; 36 degrees 40 minutes 52 seconds north latitude and 114 degrees 17 minutes 5 second west longitude, NAD 83; UTM 11s 742626e, 4062934n, NAS-C.

RANGE IN CHARACTERISTICS:

Soil moisture - Usually dry, moist in some part for short periods during winter and early spring and for brief periods between July and October following convection storms; typic aridic moisture regime.

Mean annual soil temperature 65 to 71 degrees F.

Depth to salic horizon - Ranges from the surface to 25 to 35 inches.

Reaction - moderately alkaline or strongly alkaline.

Particle size control section - Clay content: 8 to 18 percent


Az horizons:

Value: 4 through 6 dry, 4 or 5 moist.
Chroma: 4 or 5 dry and 4 moist.
Salinity (EC): 30 to 40 mmhos/cm.
Other features: 1 to 2 millimeter thick salt crust on the surface of the soil.

Byz horizon:

Hue 5YR, 7.5YR or 10YR.
Value: 5 or 6 dry, 4 or 5 moist.
Chroma: 4 or 5 dry, 5 or 6 moist.
Texture: Silty clay loam or silt loam stratified with very fine sandy loam or loamy fine sand.
Structure: subangular or angular blocky.
Salinity (EC): 35 to 45 mmhos/cm.
Calcium carbonate equivalent: 5 to 15 percent in the less than 2 millimeter fraction.
Other features: fine gypsum masses in matrix.

2Byz horizons:

Hue 5YR, 7.5YR or 10YR.
Value: 5 or 6 dry, 4 or 5 moist.
Chroma: 4 or 5 dry, 4 through 6 moist.
Texture: loamy fine sand, very fine sandy loam with minor strata of loam through silty clay loam.
Structure: massive or single grained
Salinity (EC): 5 to 20 mmhos/cm.
Calcium carbonate equivalent: 5 to 10 percent in the less than 2 millimeter fraction.
Other features: fine gypsum masses in matrix.

COMPETING SERIES: There are no competing series at this time.

GEOGRAPHIC SETTING: Black Butte soils are on flood plains with slopes between 0 and 2 percent Parent materials have been derived from a wide mixture of rocks but are dominantly from sedimentary formations including limestone, sandstone, shale, and Precambrian gneiss and shist. Elevations range from 1,200 to 2,000 feet. The climate is arid with warm, moist winters and hot, dry summers. The mean annual precipitation is about 5 to 7 inches, mean annual temperature is about 66 to 68 degrees F., and the frost-free period is 180 to 300 days.

GEOGRAPHICALLY ASSOCIATED SOILS: These are the Land, Toquop and Virgin River series. Land soils have a fine-silty particle size control section. Toquop soils lack a salic horizon and have a sandy particle size control section. Virgin River has a fine particle size control section and are somewhat poorly drained.

DRAINAGE AND PERMEABILITY: Moderately well drained; low runoff; moderately slow permeability.

USE AND VEGETATION: Rangeland and recreation use. The present vegetation is mainly Quailbush, arrowweed, pickelweed, tamarisk and honey mesquite.

DISTRIBUTION AND EXTENT: Southern Nevada. These soils are not extensive. MLRA 30.

MLRA SOIL SURVEY REGIONAL OFFICE (MO) RESPONSIBLE: PHOENIX, ARIZONA

SERIES ESTABLISHED: Virgin River Area, Nevada-Arizona, 1970.

REMARKS: Type location for the Black Butte series was moved and reclassified to better represent the series concept. Formally classified as fine-loamy over sandy or sandy-skeletal, mixed, calcareous, thermic Typic Torriorthents

Additional data: This pedon has been sampled and characterized by the NSSL, reference S04NV-003002-1, 8.

Diagnostic horizons and features recognized in this pedon are:

Ochric epipedon - The zone from about 0 to 2 inches. (A horizon)

Salic horizon - The zone from the surface to about 13 inches. (Az1, Az2 and Byz horizons)

Particle-size control section - The zone from 10 to 40 inches (The lower part of the Byz and the 2Byz1, 2Byz2, 2Byz2, and the upper part of the 3C1 horizon).

Responsibility for this series was transferred from Davis to Phoenix 4/2015. The last revision to the series was 3/2007. ET

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National Cooperative Soil Survey
U.S.A.