LOCATION PAHRANAGAT NV+UTEstablished Series
TAXONOMIC CLASS: Fine-silty, mixed, superactive, calcareous, mesic Fluvaquentic Endoaquolls
TYPICAL PEDON: Pahranagat silt loam, cultivated. (Colors are for dry soil unless otherwise noted.)
Ap--0 to 4 inches; brown (10YR 4/3) silt loam, dark brown (10YR 3/3) moist; strong very fine and fine subangular blocky structure; slightly hard, very friable, slightly sticky and plastic; many very fine and fine and few medium roots; common very fine and fine and few medium and coarse tubular pores; slightly effervescent; moderately alkaline (pH 8.0); abrupt smooth boundary. (0 to 6 inches thick)
Ag--4 to 16 inches; grayish brown (10YR 5/2) silty clay loam, very dark brown (10YR 2/2) moist; few fine distinct dark brown (7.5YR 3/4) mottles; strong fine subangular blocky structure; slightly hard, friable, sticky and very plastic; common very fine through coarse roots; common very fine through coarse tubular pores; common medium dark gray (10YR 4/1) and black (10YR 2/1) worm casts; strongly effervescent; moderately alkaline (pH 8.2); clear wavy boundary. (10 to 14 inches thick)
2Cg--16 to 25 inches; light gray (10YR 7/2) very fine sandy loam, dark grayish brown (10YR 4/2) moist; few fine faint brown (7.5YR 4/4) mottles; massive; slightly hard, very friable, slightly sticky and slightly plastic; common fine and medium roots; common medium and coarse tubular pores; common medium dark gray (10YR 4/1) and black (10YR 2/1) worm casts; strongly effervescent; moderately alkaline (pH 8.4); clear wavy boundary. (1 to 10 inches thick)
3Agb--25 to 35 inches; light brownish gray (10YR 6/2) silty clay, very dark brown (10YR 2/2) moist; few fine distinct brown (7.5YR 4/4) mottles; strong fine subangular blocky structure; hard, firm, very sticky and very plastic; common medium roots; few medium and coarse tubular pores; violently effervescent; strongly alkaline (pH 8.6); clear wavy boundary. (1 to 10 inches thick)
4Cg1--35 to 45 inches; light gray (10YR 7/2) silty clay loam, dark grayish brown (10YR 4/2) moist; many medium distinct olive brown (2.5Y 4/4) and few fine distinct brown (7.5YR 4/4) mottles; massive; hard, firm, sticky and very plastic; few medium roots; few medium tubular pores; violently effervescent; strongly alkaline (pH 8.6); clear wavy boundary. (1 to 10 inches thick)
4Cg2--45 to 60 inches; light brownish gray (2.5Y 6/2) silty clay loam, dark grayish brown (2.5Y 4/2) moist; common fine prominent brown (7.5YR 4/4) mottles; massive; hard, firm, sticky and very plastic; few medium roots; few medium tubular pores; violently effervescent; strongly alkaline (pH 8.6).
TYPE LOCATION: Lincoln County, Nevada; approximately 5000 feet west of Barclay; about 1400 feet west and 2300 feet south of the northeast corner of section 16, T. 5 S., R. 69 E.; 37 degrees, 30 minutes, and 51 seconds north latitude, 114 degrees, 16 minutes, and 27 seconds west longitude.
RANGE IN CHARACTERISTICS:
Soil moisture - Saturated for at least one or more months during most years.
Soil temperature - 53 to 59 degrees F.
Mollic epipedon thickness - 10 to 20 inches.
Reaction - Moderately alkaline or strongly alkaline.
Carbonates - Slightly effervescent to violently effervescent.
Other features: One or more buried Ag horizons range in thickness from 1 to 10 inches.
Control section - Clay content: Averages between 18 and 35 percent.
Other features: Averages less than 15 percent fine and coarser sand when mixed.
Ag horizon - Hue: 10YR or 2.5Y.
Value: 4 or 5 dry, 2 or 3 moist.
Chroma: 1 or 2.
Other features: This horizon averages about 3 to 8 percent organic matter and ranges from 1.5 to 20 percent. Some pedons have 4 inches or less of lightly colored overwash on the surface.
C horizons - Hue: 10YR through 5Y.
Value: 5 through 7 dry, 3 through 5 moist.
Chroma: 1 or 2.
Texture: Stratified very fine sandy loam, loam, silt loam, silty clay and silty clay loam.
COMPETING SERIES: These are the Colville(WA), Gibbon(NE), Kittitas(WA) and Paranat(NV) soils. (These series are expected to reclassify as Endoaquolls) Colville soils have a cambic horizon and a Bq and Cq horizons. Gibbon soils have 5 to 15 percent calcium carbonates equivalent throughout the control section and receive 20 to 30 inches of precipitation. Kittitas soils have more than 15 percent exchangeable sodium in the mollic epipedon. Paranat soils have mean annual soil temperature of 47 to 52 degrees F.
GEOGRAPHIC SETTING: Pahranagat soils are on smooth, gently convex or gently concave floodplains, alluvial fans, or basins. These soils formed in mixed alluvium derived from igneous and sedimentary rocks. Slopes are 0 to 4 percent. Elevations are 3500 to 5500 feet. The mean annual precipitation is 8 to 12 inches; the mean annual temperature is 51 to 57 degrees F., and the frost-free season is about 170 days.
GEOGRAPHICALLY ASSOCIATED SOILS: These are the Ash Springs, Bastian, Heist, and Patter soils. Ash Springs soils have coarse-loamy control sections and calcic horizons. Bastian soils have fine-loamy control sections and contain durinodes. Heist soils have coarse-loamy control sections and are well drained. Patter soils have coarse-loamy control sections and a cambic horizon.
DRAINAGE AND PERMEABILITY: Very poorly or poorly drained; runoff is very slow; moderately slow permeability. The water table ranges from at or near the soil surface in seeped areas to about 4 or 5 feet in the somewhat poorly drained areas.
USE AND VEGETATION: Used for growing alfalfa, small grains, improved grass-legume pasture, and native hay or pasture. The native vegetation is mainly sedges and carex.
DISTRIBUTION AND EXTENT: Southeastern Nevada and southwestern Utah. MLRA 29. These soils are not extensive.
MLRA OFFICE RESPONSIBLE: Reno, Nevada
SERIES ESTABLISHED: Lincoln County, Nevada, 1940.
REMARKS: Diagnostic horizons and features recognized in this pedon are:
Mollic epipedon - The surface to 16 inches (Ap and Ag horizons).
Particle-size control section - The zone from 10 to 40 inches (Ag, 2Cg, 3Agb and part of the 4Cg1 horizon).
Fluventic features - This soil is stratified and has an irregular decrease in organic matter.
Classification was changed in 1992 from Haplaquolls to Endoaquolls.