LOCATION JOB NV UTEstablished Series
TAXONOMIC CLASS: Fine-loamy, mixed, superactive, calcareous, mesic Oxyaquic Torrifluvents
TYPICAL PEDON: Job loam--rangeland. (Colors are for dry soil unless otherwise noted.)
A--0 to 23 cm; light brownish gray (2.5Y 6/2) loam, very dark grayish brown (2.5Y 3/2) moist; weak medium and fine granular structure; slightly hard, friable, slightly sticky and nonplastic; many very fine, many fine, and few medium roots; many very fine and fine interstitial pores; strongly effervescent; strongly alkaline (pH 8.6); abrupt wavy boundary. (6 to 28 cm thick)
Bk1--23 to 64 cm; light brownish gray (10YR 6/2) stratified fine sandy loam and very fine sandy loam, dark grayish brown (10YR 4/2) moist; massive; slightly hard, very friable, nonsticky and nonplastic; many very fine and many fine roots; many very fine and fine tubular, and many very fine interstitial pores; secondary carbonates segregated as few fine prominent very pale brown (10YR 8/2) filaments; slightly effervescent; strongly alkaline (pH 8.5); abrupt smooth boundary. (36 to 48 cm thick)
Bk2--64 to 81 cm; grayish brown (2.5Y 5/2) clay loam, dark grayish brown (2.5Y 4/2) moist; weak medium prismatic structure; very hard, friable, moderately sticky and moderately plastic; many very fine and many fine roots; many very fine and many fine tubular pores; secondary carbonates segregated as few fine and few very fine prominent very pale brown (10YR 8/2) filaments; violently effervescent; strongly alkaline (pH 8.5); abrupt smooth boundary. (15 to 23 cm thick)
Bk3--81 to 130 cm; light brownish gray (2.5Y 6/2) loam, dark grayish brown (2.5Y 4/2) moist; massive; hard, friable, slightly sticky and slightly plastic; few very fine and few fine roots; many very fine and many fine tubular pores; secondary carbonates segregated as few very fine and few fine very pale brown (10YR 8/2) filaments; slightly effervescent matrix and strongly effervescent filaments; moderately alkaline (pH 8.4); clear wavy boundary. (43 to 61 cm thick)
Akb--130 to 152 cm; grayish brown (2.5Y 5/2) clay loam, very dark grayish brown (2.5Y 3/2) moist; weak fine subangular blocky structure; hard, friable, slightly sticky and slightly plastic; few very fine and fine roots; few very fine tubular and interstitial pores; secondary carbonates segregated as common fine and medium prominent light gray (10YR 7/2) filaments; violently effervescent; moderately alkaline (pH 8.3).
TYPE LOCATION: Douglas County, Nevada; in Carson Valley about 2.5 miles northwest of Minden; 2,300 feet north and 2,100 feet west of the southeast corner of section 14, T. 13 N., R. 19 E.; USGS Minden 7.5 minute topographic quadrangle; 38 degrees 59 minutes 22 seconds north latitude and 119 degrees 48 minutes 49 seconds west longitude, NAD 27.
RANGE IN CHARACTERISTICS:
Soil moisture - Usually dry in the moisture control section; moist in winter and spring; dry in summer and fall unless irrigated; aridic moisture regime that borders on xeric.
Mean annual soil temperature - 9.0 to 12.0 degrees C.
Other features: Some pedons do not have Bk horizons with identifiable secondary carbonates.
Control section - Clay content: Averages 18 to 30 percent.
Rock fragments: 0 to 15 percent.
A or Ap horizons - Hue 10YR or 2.5Y.
Value: 3 or 4 moist.
Chroma: 2 or 3
Reaction: Moderately alkaline or strongly alkaline.
Bk horizons and C or Akb horizons (when present) - Hue: 10YR or 2.5Y.
Value: 5 to 7 dry, 3 to 6 moist.
Chroma: 1 through 4, dry or moist.
Texture: Stratified fine sandy loam to clay loam. Some pedons have subhorizons of sand, clay loam, clay, or gravelly material below 100 cm.
Clay content: 10 to 25 percent in upper subhorizons and 20 to 35 percent in lower subhorizons.
Reaction: Moderately alkaline or strongly alkaline.
Salinity (EC): 0 to 8 mmhos/cm.
Sodicity (SAR): 0 to 30.
Effervescence: Slightly effervescent to violently effervescent.
Identifiable secondary carbonates (present in some pedons): Occurs as few fine or very fine filaments.
Calcium carbonate equivalent: 1 to 10 percent.
Redoximorphic features: Some pedons have redox concentrations as masses of iron accumulation and redox depletions as zones of iron depletion below 100 cm.
COMPETING SERIES: This is the Hambrick (T) series. Hambrick soils have a typic aridic moisture regime, and EC more than 8 mmhos/cm.
GEOGRAPHIC SETTING: Job soils are on flood plains and flood plain steps. These soils formed in alluvium derived from mixed sources but with a strong influence from granitic rocks. Slopes are 0 to 2 percent. Elevations range from 1,400 to 1,645 meters. The climate is semiarid with cool, moist winters and warm, dry summers. The mean annual precipitation is 200 to 300 mm, mean annual temperature is 8 to 10.5 degrees C., and the frost-free period is 90 to 140 days.
GEOGRAPHICALLY ASSOCIATED SOILS: These are the Mindlebaugh, Heidtman, Settlemeyer, and Voltaire soils. All these soils have mollic epipedons.
DRAINAGE AND PERMEABILITY: Moderately well drained; low surface runoff; moderate permeability; moderately high or high Ksat class. Endosaturation is present with an apparent seasonal high water table between 90 and 152 cm (moderately deep and deep free water occurrence classes). Cumulative annual duration classes are Common or Persistent. Drainage has been altered in some areas resulting in the water table rising to within 60 cm of the soil surface during spring and early summer. These soils are susceptible to occasional to very rare flooding for brief periods.
USE AND VEGETATION: Job soils are used for rangeland and irrigated cropland. Crops are mainly alfalfa or alfalfa-grass hay. The vegetation in rangeland is mainly rubber rabbitbrush, sweetclover, bluegrass, sedges, strawberry clover, inland saltgrass, and annual forbs.
DISTRIBUTION AND EXTENT: Western Nevada. These soils are not extensive. MLRA 26, 28A.
MLRA OFFICE RESPONSIBLE: Reno, Nevada.
SERIES ESTABLISHED: Douglas County, Nevada, 1981.
REMARKS: The revision in 2000 changed the particle-size class from coarse-loamy to fine-loamy and updated the taxonomic subgroup from Aquic Xerofluvents to Oxyaquic Torrifluvents.
Diagnostic horizons and features recognized in this pedon are:
Ochric epipedon - The zone from the soil surface to 23 cm (A horizon).
Identifiable secondary carbonates - The zone from 23 to 152 cm (Bk1, Bk2, Bk3, and Akb horizons).
Endosaturation feature - The condition of ground water with an upper boundary between 90 and 152 cm at certain times during normal years (Bk3 and Akb
horizons).
Particle-size control section - The zone from 25 to 100 cm (Bk2 horizon and parts of the Bk1 and Bk3 horizons).