LOCATION BOLTZ                   NV

Established Series
Rev. SES-TM-JVC-JBF
12/2019

BOLTZ SERIES


The Boltz series consists of moderately deep, well drained soils that formed in colluvium over residuum derived from andesitic tuff-breccia. Boltz soils are on plateaus. Slopes are 4 to 30 percent. The mean annual precipitation is about 360 mm and the mean annual temperature is about 7 degrees C.

TAXONOMIC CLASS: Ashy, glassy, frigid Vitritorrandic Haploxerolls

TYPICAL PEDON: Boltz gravelly ashy sandy loam--rangeland (Colors are for dry soil unless otherwise noted.)

A1--0 to 8 cm; brown (10YR 5/3) gravelly ashy sandy loam, dark brown (10YR 3/3) moist; weak fine subangular blocky structure; soft, very friable, nonsticky and nonplastic; common very fine roots; many very fine interstitial pores; 10 percent cinders, 5 percent obsidian gravel and 1 percent cobbles; slightly acid (pH 6.4); clear wavy boundary. (5 to 13 cm thick)

A2--8 to 28 cm; brown (7.5YR 5/2) gravelly ashy sandy loam, dark brown (7.5YR 3/2) moist; moderate fine and medium subangular blocky structure; soft, very friable, slightly sticky and nonplastic; many very fine, common fine and few medium roots; many very fine tubular pores; 15 percent cinders and glassy vesicular gravel; neutral (pH 6.8); clear wavy boundary. (10 to 23 cm thick)

Bw--28 to 51 cm; brown (7.5YR 5/4) gravelly ashy sandy loam, brown (7.5YR 4/4) moist; moderate medium subangular blocky structure; slightly hard, very friable, slightly sticky and slightly plastic; common very fine and fine, few medium roots; many very fine and common fine tubular pores; 10 percent cinders and 5 percent glassy vesicular gravel; neutral (pH 6.8); clear wavy boundary. (20 to 38 cm thick)

2C--51 to 86 cm; light yellowish brown (10YR 6/4) gravelly ashy sandy loam, dark yellowish brown (10YR 4/4) moist; weak coarse subangular blocky structure; slightly hard, very friable, nonsticky and nonplastic; common very fine, few fine and medium roots; many very fine interstitial and common very fine tubular pores; 20 percent cinders and glassy vesicular gravel; neutral (pH 7.0); clear wavy boundary. (13 to 30 cm thick)

2Cr--86 cm; very pale brown (10YR 7/4) soft, weathered andesitic tuff-breccia; can be dug with difficulty; many glassy vesicular gravel; many distinct silica coats on bedrock.

TYPE LOCATION: Washoe County, Nevada; about 17 miles east-southeast of Vya; about 270 feet south and 740 feet west of the northeast corner of section 30, T. 42 N., R. 22 E.; USGS Massacre Creek 7.5 minute topographic quadrangle; latitude 41 degrees 32 minutes 1.8 seconds N and longitude 119 degrees 32 minutes 29.2 seconds W; WGS84 Decimal Degrees 41.5338333 latitude, -119.5414444 longitude.

RANGE IN CHARACTERISTICS:
Soil moisture: Moist in the moisture control section in winter and spring; dry from July through October; aridic soil moisture regime that borders on xeric.
Mean annual soil temperature: 7 to 8 degrees C.
Mollic epipedon thickness: 25 to 40 cm.
Depth to bedrock: 50 to 100 cm to a paralithic contact. The paralithic materials below the contact are tuff-breccia, conglomerate, or tuff.
Volcanic glass content: 60 to 95 percent, mainly as glass shards in the coarse silt through fine sand fractions.
Reaction: Slightly acid or neutral.

Particle-size control section - Clay content: 10 to 18 percent.
Rock fragments: 15 to 25 percent, mainly gravel. Lithology of fragments is pyroclastic and similar volcanic rocks such as cinders or obsidian.

A horizons
Value: 5 or 6 dry, 2 or 3 moist. A dry value of 6 is only in the upper 5 cm in some pedons and the upper 18 cm when mixed has a dry value of 5.
Chroma: 2 or 3, dry or moist.
Organic matter content: 1 or 2 percent.

Bw horizon
Hue: 10YR or 7.5YR.
Value: 5 or 6 dry, 3 or 4 moist.
Chroma: 3 or 4, dry or moist.
Clay content: 10 to 18 percent.

2C horizon
Chroma: 3 or 4, dry or moist.
Clay content: 10 to 18 percent.

COMPETING SERIES: These are the Bonnick, Borobey, Emamount, Embal, Frentera, Gardone, Oatmanflat, Picturerock, Stookmoor, Tuffcabin, and Wegert series.

Bonnick, Borobey, Emamount, Embal, Gardone, and Picturerock soils are very deep. Frentera, Stookmoor, and Wegert soils are moderately deep to lithic contacts. Oatmanflat and Tuffcabin soils are deep to buried duripans.

GEOGRAPHIC SETTING: Boltz soils are on plateaus. They occur on north-facing shoulder and backslope positions. These soils formed in colluvium over residuum derived from andesitic tuff-breccia, conglomerate, and similar pyroclastic or volcaniclastic rocks. Slopes are 4 to 30 percent. Elevations range from 1,770 to 2,125 meters. The mean annual precipitation is 300 to 400 mm, the mean annual temperature is 6 to 7 degrees C, and the frost-free period is 80 to 100 days.

GEOGRAPHICALLY ASSOCIATED SOILS: These are the Hart Camp, Tusune, and Westbutte soils.

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

USE AND VEGETATION: Boltz soils are used for livestock grazing and wildlife habitat. The present vegetation is dominantly mountain big sagebrush, antelope bitterbrush, Idaho fescue, and needlegrass.

DISTRIBUTION AND EXTENT: Northwestern Nevada. These soils are not extensive with about 1,200 acres of the series mapped to date. MLRA 23.

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

SERIES ESTABLISHED: Washoe County (North Part), Nevada, 1995.

REMARKS: Diagnostic horizons and features recognized in this pedon are:
Mollic epipedon - The zone from the soil surface to 28 cm (The A1 and A2 horizons).
Cambic horizon - The zone from 28 to 51 cm (The Bw horizon).
Vitrandic intergrade feature - The zone from the soil surface to 76 cm (The A1, A2, and Bw horizons and part of the 2C horizon).
Paralithic contact - The boundary at 86 cm to underlying soft bedrock (2Cr layer).
Particle-size control section and ashy substitute class with glassy mineralogy - The zone from 25 to 86 cm (Part of the A2 horizon and the Bw and C horizons).

ADDITIONAL DATA: Volcanic glass and glass aggregates in the sand fraction determined locally by optical grain count. The typical pedon at the series type location has full characterization data from the Soil Survey Laboratory (SSL), Lincoln, NE, as soil survey sample number S98NV-031-010 (pedon # 99P0163).


National Cooperative Soil Survey
U.S.A.