LOCATION BROWNSBOWL              NV CA

Established Series
Rev. JBF/TM
12/2019

BROWNSBOWL SERIES

The Brownsbowl series consists of very deep, well drained soils that formed in volcanic ash and colluvium derived from andesite. Brownsbowl soils are on plateaus and mountains. Slopes are 8 to 50 percent. The mean annual precipitation is about 380 mm and the mean annual temperature is about 6.7 degrees C.

TAXONOMIC CLASS: Ashy, glassy Vitrandic Haplocryolls

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

A1--0 to 8 cm; dark grayish brown (10YR 4/2) crushed, gravelly ashy sandy loam, black (10YR 2/1) crushed, moist; moderate very fine granular structure; soft, very friable, nonsticky, nonplastic; many very fine and fine, common medium and coarse roots throughout; many very fine and fine interstitial pores; 5 percent fine gravel and 10 percent gravel; neutral, (pH 6.8); abrupt wavy boundary.

A2--8 to 25 cm; dark grayish brown (10YR 4/2) crushed, gravelly ashy sandy loam, black (10YR 2/1) crushed, moist; strong fine subangular blocky structure; soft, very friable, nonsticky and nonplastic; many very fine and fine, common medium and coarse roots throughout; many very fine interstitial and tubular pores; 10 percent fine gravel and 5 percent gravel; neutral, (pH 6.6); abrupt wavy boundary.

A3--25 to 48 cm; dark grayish brown (10YR 4/2) crushed, gravelly ashy sandy loam, very dark brown (10YR 2/2) crushed, moist; moderate fine and medium subangular blocky structure; soft, very friable, nonsticky and nonplastic; many very fine, common fine to coarse roots throughout; common fine tubular, many very fine interstitial and tubular pores; 10 percent fine gravel and 5 percent gravel; slightly acid, (pH 6.4); clear wavy boundary.

A4--48 to 71 cm; brown (10YR 4/3) crushed, gravelly ashy sandy loam, very dark brown (10YR 2/2) crushed, moist; moderate fine and medium subangular blocky structure; soft, very friable, nonsticky and nonplastic; many very fine, common fine to very coarse roots throughout; few fine tubular, many very fine interstitial and tubular pores; 10 percent fine gravel and 5 percent gravel, 5 percent cobbles; slightly acid, (pH 6.1); clear wavy boundary.

A5--71 to 86 cm; brown (10YR 4/3) crushed, cobbly ashy sandy loam, very dark brown (10YR 2/2) crushed, moist; moderate fine and medium subangular blocky structure; soft, very friable, nonsticky and nonplastic; many very fine, common fine to very coarse roots throughout; few fine tubular, many very fine interstitial and tubular pores; 10 percent fine gravel and 5 percent gravel, 10 percent cobbles; moderately acid, (pH 6.0); clear wavy boundary. (Combined thickness of A horizons is 69 to 100 cm)

2A--86 to 104 cm; brown (10YR 4/3) crushed, very gravelly ashy sandy loam, very dark brown (10YR 2/2) crushed, moist; moderate fine subangular blocky structure; soft, very friable, nonsticky and nonplastic; many very fine, common fine to coarse roots throughout; many very fine interstitial and tubular pores; 10 percent fine gravel and 15 percent gravel, 15 percent cobbles; moderately acid, (pH 6.0); clear wavy boundary. (15 to 20 cm thick)

2Bw--104 to 154 cm; yellowish brown (10YR 5/4) crushed, extremely cobbly ashy fine sandy loam, dark yellowish brown (10YR 3/4) crushed, moist; weak fine subangular blocky structure; soft, very friable, nonsticky and nonplastic; many very fine, common fine to coarse roots throughout; many very fine interstitial pores; 5 percent fine gravel and 25 percent gravel, 30 percent cobbles, 1 percent stones; moderately acid, (pH 6.0).

TYPE LOCATION: Washoe County, Nevada; in the Hays Canyon Range; about 1/2 mile west of Mountain View Spring; section 1, T. 39 N., R. 18 E. USGS Hayes Canyon 7.5 minute topographic quadrangle; 41 degrees 17 minutes 50.1 seconds north latitude and 119 degrees 54 minutes 31.6 seconds west longitude; WGS84 Decimal Degrees 41.2973611 latitude, -119.9098889 longitude.

RANGE IN CHARACTERISTICS:

Soil moisture - Moist in winter and spring, dry in late summer and fall; completely dry for at least 45 consecutive days between July and October; xeric moisture regime that borders on aridic.
Mean annual soil temperature - 6.7 to 8.3 degrees C.
Mean summer soil temperature - 12.2 to 15.0 degrees C.
Mollic epipedon thickness - 100 to 117 cm.
Depth to very cobbly or extremely cobbly lithologic discontinuity - 69 to 100 cm.
Volcanic glass content - 50 to 80 percent in the coarse silt through fine sand fractions.

Control section - Clay content: 5 to 10 percent.
Rock fragments: Averages 20 to 35 percent hard volcanic rocks.

A horizons
Structure: subangular blocky or weak angular blocky, upper subhorizons are granular in some pedons.
Rock fragments: 15 to 20 percent gravel, 0 to 15 percent cobbles.
Reaction: neutral to moderately acid, commonly decreasing with depth.

2A horizon
Structure: weak or moderate subangular blocky.
Rock fragments: 20 to 30 percent gravel, 15 to 25 percent cobbles.
Reaction: Moderately acid or slightly acid.

2Bw horizon
Value: 5 or 6 dry.
Chroma: 3 or 4, dry or moist.
Structure: Weak angular blocky or weak or moderate subangular blocky.
Consistence: Slightly hard or hard dry.
Rock fragments: 30 to 40 percent gravel, 25 to 45 percent cobbles; 1 to 5 percent stones.
Reaction: Moderately acid or slightly acid.

COMPETING SERIES: These are Anniecreek and Cadero series. Anniecreek soils have a Mollic epipedon 38 to 64 cm thick. Cadero soils have paralithic contact at 50 to 100 cm.

GEOGRAPHIC SETTING: Brownsbowl soils are on north facing concave sideslopes of plateaus and mountains. They formed in volcanic ash and colluvium derived from andesite. Slopes are 8 to 50 percent. Elevations range from 1,400 to 2,475 meters. The mean annual precipitation is 300 to 410 mm, mean annual temperature is 6.1 to 7.2 degrees C., and the frost-free period is 60 to 80 days. These soils receive additional moisture from adjacent areas.

GEOGRAPHICALLY ASSOCIATED SOILS: These are the Hashwoods (T)(NV) and Hutchley soils. Hashwoods soils are deep and have argillic horizons. Hutchley soils are shallow to hard bedrock and have loamy-skeletal argillic horizons.

DRAINAGE AND PERMEABILITY: Well drained; low or medium surface runoff; moderately rapid permeability.

USE AND VEGETATION: Brownsbowl soils are used for livestock grazing and wildlife habitat. The present vegetation is mainly mountain big sagebrush, snowberry, needlegrass and mountain brome.

DISTRIBUTION AND EXTENT: Western Washoe County, Surprise Valley-Home Camp Area; MLRA 23. These soils are not extensive.

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

SERIES ESTABLISHED: Surprise Valley-Home Camp Area, California and Nevada, 2002

REMARKS: Diagnostic horizons and features recognized in this pedon are:
Mollic epipedon - The zone from the soil surface to 102 cm (The A1, A2, A3, A4, A5 and 2A horizons).
Cambic horizon - The zone from 102 to 154 cm (The 2Bw horizon).

Particle size control section and ashy substitute class with glassy mineralogy - The zone from 25 to 100 cm.

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National Cooperative Soil Survey
U.S.A.