LOCATION PHIZPHRE AZEstablished Series
TAXONOMIC CLASS: Loamy-skeletal, mixed, superactive, mesic Aridic Lithic Argiustolls
TYPICAL PEDON: Phizphre very gravelly loam - recreation and wildlife habitat. (Colors are for dry soil unless otherwise stated.)
A--0 to 2 inches; brown (7.5YR 4/3) very gravelly loam; very dark brown (7.5YR 2.5/2) moist; weak fine subangular blocky structure parting to strong very fine granular; soft, very friable, slightly sticky and slightly plastic; common very fine and fine roots; many very fine and common fine irregular pores; few fossil brachiopods; noneffervescent; 50 percent gravel, 5 percent cobble; neutral (pH 6.6); abrupt smooth boundary. (2 to 3 inches thick.)
Bw--2 to 7 inches; brown (7.5YR 4/3) very cobbly silt loam; very dark brown (7.5YR 2.5/2) moist; strong fine and medium subangular blocky structure; very hard, friable, moderately sticky and moderately plastic; common very fine through medium and few coarse roots; common very fine and fine tubular pores; few fossil brachiopods; noneffervescent; 20 percent gravel, 20 percent cobble; neutral (pH 6.8); clear wavy boundary. (4 to 7 inches thick.)
Bt--7 to 19 inches; brown (7.5YR 4/4) extremely cobbly silty clay loam; very dark brown (7.5YR 2.5/3) moist; strong fine and medium subangular blocky structure; hard, firm, very sticky and very plastic; common fine through coarse roots; common fine and medium and few coarse tubular pores; common faint clay films on faces of peds and lining pores; few fossil brachiopods; many strong brown (7.5YR 5/6) and strong brown (7.5YR 5/8) 1 to 5 millimeter thick laminar silica concretions occurring as irregular bands on cobbles; few thin lime coats on underside of coarse fragments; noneffervescent; 5 percent gravel, 55 percent cobble; neutral (pH 7.0); abrupt irregular boundary. (7 to 12 inches thick.)
R--19 inches; limestone bedrock.
TYPE LOCATION: Mohave County, Arizona; located about 2,350 feet south and 2,225 feet east of the northwest corner of sec. 19, T. 29 S., R. 10 W.; 35 degrees, 53 minutes, 53 seconds north latitude and 113 degrees, 24 minutes, 7 seconds west longitude.
RANGE IN CHARACTERISTICS:
Soil moisture: usually dry in some part for 90 or more days cumulative and is moist in some part for 45 consecutive days during June through October and more than half the time the soil temperature is above 41 degrees F. The soil is driest in May and June. Aridic ustic soil moisture regime.
Soil temperature: 52 to 58 degrees F.
Rock fragments: 40 to 60 percent, dominated by cobble.
Depth to bedrock: 14 to 20 inches.
Reaction: slightly acid or neutral.
Soil profile contains few to common fossilized brachiopods.
A horizon
Hue: 7.5YR, 10YR
Value: 4 or 5 dry, 2.5 or 3 moist.
Chroma: 2 or 3 dry or moist.
Bw horizon
Hue: 7.5YR, 10YR
Value: 4 or 5 dry, 2.5 or 3 moist.
Chroma: 2 or 3 dry or moist.
Bt horizon
Hue: 5YR, 7.5YR
Value: 3 to 5 dry, 2.5 or 3 moist.
Chroma: 4 or 6 dry, 3 or 4 moist.
Texture of the fine earth: clay loam, silty clay loam
Clay content: 30 to 35 percent.
COMPETING SERIES: These are the
Buckspring (NV),
Montvale (UT),
Motoqua (UT),
Santa Fe (NM), and
Slidymtn (NV) series.
Buckspring, Montvale, soils have horizons with secondary calcium carbonate accumulations.
Motoqua soils formed in material weathered from acid igneous rocks and have a mollic epipedon that extends into the upper part of the Bt horizon and may or may not includes the entire profile in some pedons.
Santa Fe soils have a mollic epipedon that extends to bedrock and formed in granite and related rocks.
Slidymtn soils formed in parent material derived from andesite, rhyolite and related volcanic rocks.
GEOGRAPHIC SETTING: Phizphre soils are on summits and shoulders of plateaus. These soils formed in residuum and colluvium weathered from limestone of the Kaibab formation. Slopes are 8 to 15 percent. Elevations are 5,900 to 6,200 feet. The mean annual precipitation is 12 to 18 inches. The mean annual air temperature is 48 to 56 degrees F. The frost-free period is 135 to 150 days.
GEOGRAPHICALLY ASSOCIATED SOILS: These are the nearby Disterheff, Natank and Yumtheska soils. Disterheff and Natank soils have bedrock at depths greater than 20 inches. Yumtheska soils have a calcic horizon and do not have an argillic horizon.
DRAINAGE AND PERMEABILITY: Well drained; low to medium runoff; moderately slow permeability.
USE AND VEGETATION: Phizphre soils are used for recreation and wildlife habitat. The present vegetation is turbinella oak, manzanita, silktassel, desert ceanothus, Utah juniper and pinyon pine.
DISTRIBUTION AND EXTENT: Northern Arizona, MLRA is 38. Phizphre soils are not extensive.
MLRA SOIL SURVEY REGIONAL OFFICE (MO) RESPONSIBLE: Phoenix, Arizona
SERIES ESTABLISHED: Mohave County, Arizona, soil survey of Lake Mead National Recreation Area, and Grand Canyon soil survey area 2001.
REMARKS: Diagnostic horizons and features recognized in this pedon are:
Mollic epipedon - The zone from 0 to 7 inches (A and Bw horizons)
Argillic horizon - The zone from 7 to 19 inches (Bt horizon)
Lithic contact - The boundary at 19 inches (R horizon)
Classification changed to Aridic Lithic subgroup in 2006.
Classified according to Keys to Soil Taxonomy Tenth Edition, 2006.