LOCATION IDOW IDEstablished Series
TAXONOMIC CLASS: Fine-loamy, mixed, superactive, mesic Xeric Argidurids
TYPICAL PEDON: Idow loam--cropland. On a 2 percent slope, southwest aspect, 3,830 feet elevation. (Colors are for air dry soil unless otherwise noted.) When described on October 7, 1986, the soil was dry throughout.
Ap1--0 to 3 inches; yellowish brown (10YR 5/4) loam, dark brown (10YR 3/3) moist; weak fine granular structure; slightly hard, friable, slightly sticky and slightly plastic; common very fine and fine, few medium roots; very fine and fine irregular pores; neutral (pH 7.1); gradual smooth boundary. (2 to 6 inches thick)
Ap2--3 to 7 inches; yellowish brown (10YR 5/4) loam, dark brown (10YR 3/3) moist; moderate fine granular structure; slightly hard, friable, slightly sticky and slightly plastic; common very fine and fine, few medium roots; common very fine and few fine irregular pores; neutral (pH 7.1); clear smooth boundary. (3 to 6 inches thick)
Bt1--7 to 12 inches; yellowish brown (10YR 5/4) loam, brown (10YR 4/3) moist; moderate medium subangular blocky structure; slightly hard, friable, slightly sticky and slightly plastic; common very fine and fine, few medium roots; common fine tubular pores; common thin clay films on faces of peds and in pores; neutral (pH 6.9); gradual smooth boundary. (5 to 12 inches thick)
Bt2--12 to 23 inches; yellowish brown (10YR 5/4) loam, brown (10YR 4/3) moist; moderate medium subangular blocky structure; slightly hard, firm, sticky and plastic; few very fine roots; common fine tubular pores; common thin clay films on faces of peds and in pores; neutral (pH 7.0); gradual smooth boundary. (0 to 12 inches thick)
Bk--23 to 39 inches; very pale brown (10YR 7/3) silt loam, light yellowish brown (10YR 6/4) moist; moderate medium subangular blocky structure; slightly hard, firm, sticky and plastic; few very fine roots; few fine tubular pores; 5 percent gravel; 5 percent cobbles; violently effervescent (35 percent calcium carbonate); moderately alkaline (pH 8.2); abrupt smooth boundary. (10 to 20 inches thick)
Bkqm--39 to 60 inches; very pale brown (10YR 8/3) fractured duripan, very pale brown (10YR 7/3) moist; platy; indurated; extremely hard, extremely firm; 1/4 inch laminar silica lenses with gravelly sandy loam soil material between plates; fractures are more than 10 inches apart; violently effervescent.
TYPE LOCATION: Jerome County, Idaho; 4 miles north of Jerome City; in the northeast 1/4, northeast 1/4, northeast 1/4 section 30, T. 7 S., R. 17 E.
RANGE IN CHARACTERISTICS:
Average annual soil temperature - 49 to 53 degrees F.
Depth to duripan - 20 to 40 inches
Thickness of the duripan - greater than 18 inches
Control section averages - 20 to 30 percent clay
Depth to lime - 17 to 33 inches
Depth to bedrock - 40 inches or more
Ap horizon
Value - 4 or 5 dry, 3 or 4 moist
Chroma - 3 or 4 dry or moist
Bt horizons
Value - 5 or 6 dry, 3 or 4 moist
Chroma - 3 or 4 dry or moist
Clay - 18 to 30 percent
Texture - L, CL, SCL, or FSL
Bk or Bkq horizon
Value - 6 to 8 dry, 4 through 7 moist
Chroma - 3 or 4 dry or moist
Texture - SIL, SCL, CL, FSL, or L
Durinodes - 0 to 20 percent
Gravel content - 0 to 5 percent
Cobble content - 0 to 5 percent
Effervescence - slight through violent
COMPETING SERIES: These are the Arbidge, Dacker, Deerlodge, Ditchcamp, Drysel (T), Exel, Hager, Lembos, Ochoco, Rakane (T), Snowmore, Wako (T), Wellsed and Wendell (T), series. Arbidge soils have duripans less than 10 inches thick, and are underlain by sand and gravel. Dacker soils have silty Bt horizons. Ditchcamp and Rakane soils lack a Bk horizon. Deerlodge and Exel soils have hues redder than 10YR. Ditchcamp, Snowmore and Wendell soils are moderately deep to bedrock. Drysel soils have a massive duripan. Exel and Wellsed soils have 15 to 35 percent rock fragments in the Bt horizons, and have a duripan less than 10 inches thick. Hager soils have duripans that are 3 to 10 inches thick. Lembos soils are slightly to strongly effervescent in the Bt horizon. Ochoco soils have up to 20 percent pumice in the A and Bt horizons and have a duripan less than 10 inches thick. Waco soils have an E horizon.
GEOGRAPHIC SETTING: Idow soils are on basalt plains, buttes, and terraces. They formed in alluvium from mixed sources. Slopes range from 0 to 8 percent. Elevation ranges from 3,400 to 4,500 feet. The average annual precipitation is 9 to 11 inches. The average annual temperature is 47 to 51 degrees F. and the frost free season is 100 to 140 days.
GEOGRAPHICALLY ASSOCIATED SOILS: These are the Barrymore (T), Paulville, and Starbuck (T) soils. Barrymore soils are moderately deep to bedrock and have coarse-silty control sections. Paulville soils are very deep. Starbuck soils are shallow to bedrock. All soils are on the same landform as Idow soils.
DRAINAGE AND PERMEABILITY: Well drained, slow runoff; moderately slow permeability.
USE AND VEGETATION: Idow soils are used for rangeland and irrigated cropland. Native vegetation is Wyoming big sagebrush and Thurber needlegrass. Irrigated crops are mainly wheat, barley, beans, potatoes, sugar beets and alfalfa hay.
DISTRIBUTION AND EXTENT: This series is inextensive in south central Idaho.
MLRA SOIL SURVEY REGIONAL OFFICE (MO) RESPONSIBLE: Portland, Oregon
SERIES ESTABLISHED: Jerome County, Idaho, 1992.
REMARKS: Diagnostic horizons and features recognized in this pedon are:
Ochric epipedon - the zone from the surface to 7 inches (Ap horizon)
Argillic horizon - the zone from 7 to 23 inches (Bt1 and Bt2 horizons)
Calcic horizon - the zone from 23 to 29 inches (Bk horizon)
Duripan - the zone from 39 to 60 inches (Bkqm horizon)
Particle size control section - 7 to 23 inches (Bt1 and Bt2 horizons)