LOCATION PIZONA                  CA

Established Series
Rev. DV/TAC/AFF/MAV/GAM
04/2017

PIZONA SERIES

The Pizona series consists of deep, well drained soils. They formed in material weathered from basaltic bedrock with some volcanic ash overburden. Pizona soils are on hillsides or mountain slopes. Slopes are 8 to 50 percent. The mean annual precipitation is 200 to 300 mm and the mean annual temperature is 7 to 10 degrees C.

TAXONOMIC CLASS: Loamy-skeletal, mixed, superactive, mesic Vitrixerandic Haplargids

TYPICAL PEDON: Pizona cobbly ashy loamy sand - on a 41 percent east slope at 2,050 meters elevation under mountain big sagebrush and pinyon pine vegetation. Colors are for dry soil unless otherwise stated. When described on June 30, 1980, the soil was moist below 8 cm. The soil surface is partially covered with angular or flaggy rock fragments; 10 percent gravel, 10 percent cobbles, 3 percent stones.

A1--0 to 8 cm; light brownish gray (10YR 6/2) cobbly ashy loamy sand, dark grayish brown (10YR 4/2) moist; single grain; loose, nonsticky and nonplastic; many very fine interstitial pores; 10 percent gravel, 10 percent cobbles, and 3 percent stones; neutral (pH 6.6); abrupt irregular boundary. (5 to 8 cm thick)

A2--8 to 13 cm; light gray (10YR 7/2) cobbly ashy loamy sand, brown (10YR 5/3) moist; massive; soft, very friable, nonsticky and nonplastic; few very fine roots; common very fine vesicular pores; 5 percent gravel, 10 percent cobbles, and 3 percent stones; neutral (pH 7.3); abrupt irregular boundary. (0 to 5 cm thick)

A3--13 to 28 cm; light gray (10YR 7/2) cobbly ashy loamy sand, brown (10YR 5/3) moist; massive; soft, very friable, nonsticky and nonplastic; few very fine and fine roots; many very fine interstitial pores; 10 percent gravel, 10 percent cobbles, and 1 percent stones; neutral (pH 7.3); clear wavy boundary. (10 to 18 cm thick)

2Ab--28 to 43 cm; pale brown (10YR 6/3) gravelly sandy loam, dark yellowish brown (10YR 4/4) moist; massive; soft, very friable, nonsticky and nonplastic; few very fine and fine roots; common very fine interstitial pores; 20 percent gravel, 10 percent cobbles, and 1 percent stones; slightly alkaline (pH 7.5); clear wavy boundary. (10 to 18 cm thick)

2Btb1--43 to 61 cm; light yellowish brown (10YR 6/4) very cobbly sandy loam, dark yellowish brown (10YR 4/4) moist; weak medium subangular blocky structure; soft, very friable, slightly sticky and slightly plastic; few very fine and fine roots; few very fine tubular and interstitial pores; few faint clay films in pores and on peds; 25 percent gravel, 15 percent cobbles, 1 percent stones; slightly alkaline (pH 7.6); clear wavy boundary. (13 to 25 cm thick)

2Btb2--61 to 91 cm; light yellowish brown (10YR 6/4) very cobbly sandy clay loam, dark yellowish brown (10YR 4/4) moist; moderate fine and medium subangular blocky structure; hard, friable, moderately sticky and moderately plastic; few very fine and fine roots; few very fine tubular and interstitial pores; many faint and few distimct clay films on ped faces and in pores; 25 percent gravel, 15 percent cobbles, and 1 percent stones; slightly alkaline (p 7.7); clear wavy boundary. (20 to 38 cm thick)

2Btqb--91 to 112 cm; light yellowish brown (10YR 6/4) very cobbly sandy loam, dark yellowish brown (10YR 4/4) moist; moderate fine and medium subangular blocky structure; hard, firm, slightly sticky and slightly plastic; few very fine and fine roots; few very fine tubular and interstitial pores; common faint clay films on peds and in pores; slight silica cementation; 25 percent gravel, 15 percent cobbles, and 1 percent stones; slightly alkaline (p 7.6); abrupt wavy boundary. (13 to 36 cm thick)

2R--112 cm; hard, fractured basaltic rock; average fracture spacing 30 cm; some clay films coat rock surfaces.

TYPE LOCATION: Mono County, California. About four miles north of Benton Hot Springs; about 2,100 feet south and 1,450 feet west of the northeast corner of sec. 15, T. 1 S., R. 31 E.; USGS Benton Hot Springs 7.5 minute topographic quadrangle;; latitude 37 degrees 51 minutes 56 seconds N and longitude 118 degrees 32 minutes 18 seconds W; WGS84 Decimal Degrees 37.8636111 latitude, -118.5400000 longitude.

RANGE IN CHARACTERISTICS: Depth to basaltic bedrock is 40 to 60 inches. The soil between depths of 12 and 30 inches is usually dry from mid-May until sometime in November, and is moist in some part the rest of the time. The soil temperature is above 5 degrees C. from April 1 to December 15, and is above 8 degrees C. from April 15 to December 1. Summer thunderstorms occur, but are spotty and usually do not wet the moisture control section. The mean annual soil temperature is 8 to 13 degrees C. Most of the rock fragments are angular or flaggy basaltic fragments. Rock fragments cover 20 to 60 percent of the soil surface and in many areas project 8 to 50 cm above the soil surface. Surface stone coverage is 3 to 30 percent. The dry bulk density of the ashy overburden is 1.1 to 1.25 g/cc and the moist bulk density is 1.30 to 1.45 g/cc.

The A horizon color is 10YR 6/2 or 7/2. Moist color is 10YR 4/2, 5/2 or 5/3. . The ashy overburden is 15 to 36 cm thick. Rock fragment content is 15 to 35 percent, consisting of 5 to 15 percent gravel, 5 to 15 percent cobbles, and 3 to 15 percent stones. The organic carbon content is 0.1 to 0.3 percent.

The 2Ab horizon color is 10YR 6/2, 6/3 or 7/2. Moist color is 10YR 4/4, 4/2 or 4/3. Textures are gravelly or cobbly loamy sand or sandy loam. Rock fragment content is 20 to 35 percent, consisting of 10 to 20 percent gravel, 5 to 10 percent cobbles and 3 to 15 percent stones.

The 2Btb horizon color is 10YR 6/2, 6/3 or 6/4. Moist color is 10YR 4/2, 4/3 or 4/4. Textures are very cobbly or very stony sandy loam or sandy clay loam. Clay content ranges from 15 to 30 percent. Rock fragment content is 35 to 60 percent, consisting of 10 to 25 percent gravel, 15 to 25 percent cobbles, and 1 to 20 percent stones.

COMPETING SERIES: This is the Kayo series. Kayo soils are more than 152 cm deep and are calcareous in the substratum.

GEOGRAPHIC SETTING: Pizona soils are on hillsides and mountain slopes and occur at elevations of 1,770 to 2,320 meters. Slopes are 8 to 50 percent. The soils formed in material weathered from basaltic rock, with a subsequent aerial deposition of rhyolitic volcanic ash. The mean annual precipitation is 200 to 300 mm, much of it as snow. The mean January temperature is about -1 degrees C.; the mean July temperature is about 19 degrees C. The mean annual temperature is 7 to 10 degrees C. The frost-free season is 110 to 140 days. Some rock outcrops are associated with these soils.

GEOGRAPHICALLY ASSOCIATED SOILS: These are the Brantel, Cowtrack, and Zono soils. Brantel soils are alluvial and are ashy throughout the textural control section. Cowtrack soils have ashy over loamy control sections and frigid soil temperature regimes. Zono soils have ashy over loamy control section.

DRAINAGE AND SATURATED HYDRAULIC CONDUCTIVITY: Well drained; medium to rapid runoff; moderately slow permeability, moderately high saturated hydraulic conductivity.

USE AND VEGETATION: Used for grazing and wildlife habitat. Vegetation is mainly mountain big sagebrush, singleleaf pinyon, desert needlegrass, Indian ricegrass, antelope bitterbrush, Utah juniper, annual forbs, and perennial forbs.

DISTRIBUTION AND EXTENT: Mountainous uplands east of the Sierra Nevada in east-central California. The soils are of moderate extent. MLRA 26.

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

SERIES PROPOSED: Mono County, California; BLM Benton-Owens Valley Soil Inventory, 1983.

SOURCE OF NAME: The series is named after Pizona Creek.

REMARKS: Diagnostic horizons and features recognized in this pedon are:
Ochric epipedon - The zone from the soil surface to 43 cm (The A1, A2, A3 and 2Ab horizons).
Vitrandic zone - The zone from the soil surface to 28 cm (The A1, A2 and A3 horizons).
Argillic horizon - The zone from 43 to 112 cm (The 2Btb1, 2Btb2 and 2Btqb horizons).
Lithic contact - The boundary at 112 cm (2R horizon).
Particle-size control section - The zone from 43 to 93 cm (The 2Btb1, 2Btb2 and part of the 2Btqb horizons).
Pizona soils have an aridic moisture regime bordering on xeric. Cold soil temperatures in winter prevent their meeting all the xeric moisture regime requirements.

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National Cooperative Soil Survey
U.S.A.