LOCATION JENSEN IDEstablished Series
TAXONOMIC CLASS: Fine-loamy, mixed, superactive, frigid Calcic Pachic Argixerolls
TYPICAL PEDON: Jensen silt loam, nonirrigated cropland; on a 5 percent slope at 5080 feet elevation. When described on November 13, 1986, the soil was moist throughout. (Colors are for dry soil unless otherwise stated.)
Ap--0 to 6 inches; grayish brown (10YR 5/2) silt loam, very dark grayish brown (10YR 3/2) moist; moderate fine granular structure; soft, friable, slightly sticky and slightly plastic; many very fine tubular pores; many very fine and fine roots; 10 percent gravel; neutral (pH 7.2); clear smooth boundary. (4 to 10 inches thick)
A--6 to 12 inches; grayish brown (10YR 5/2) silt loam, very dark grayish brown (10YR 3/2) moist; weak fine subangular blocky structure parting to moderate fine granular; slightly hard, friable, slightly sticky and slightly plastic; many very fine tubular pores; many very fine and fine roots; 10 percent gravel; slightly alkaline (pH 7.4); clear smooth boundary. (4 to 12 inches thick)
Bt1--12 to 22 inches; brown (10YR 5/3) gravelly silt loam, dark brown (10YR 3/3) moist; moderate fine subangular blocky structure; slightly hard, friable, slightly sticky and slightly plastic; many fine and very fine tubular pores; common very fine and fine roots; 20 percent gravel; few faint clay films in pores; slightly alkaline (pH 7.6); clear wavy boundary. (8 to 15 inches thick)
Bt2--22 to 38 inches; brown (10YR 5/3) gravelly silt loam, dark brown (10YR 3/3) moist; moderate fine subangular blocky structure; hard, very firm, slightly sticky and slightly plastic; many fine and very fine tubular pores; common very fine and few fine roots; 20 percent gravel; few faint clay films in pores; slightly alkaline (pH 7.6); clear smooth boundary. (14 to 20 inches thick)
Bk1--38 to 45 inches; pale brown (10YR 6/3) gravelly silt loam, brown (10YR 4/3) moist; moderate fine subangular blocky structure; very hard, very firm, slightly sticky and slightly plastic; many fine and very fine tubular pores; few very fine roots; 30 percent gravel and 1 percent cobbles; strongly effervescent; many lime veins; moderately alkaline (pH 8.0); clear wavy boundary. (4 to 12 inches thick)
Bk2--45 to 60 inches; pale brown (10YR 6/3) very gravelly loam, brown (10YR 4/3) moist; moderate fine subangular blocky structure; very hard, very firm, slightly sticky and slightly plastic; many very fine tubular pores; few very fine roots; 35 percent gravel and 1 percent cobbles; strongly effervescent; many lime veins; mildly alkaline (pH 7.8).
TYPE LOCATION: Oneida County, Idaho; about 12 miles southwest of Malad; 2000 feet east and 300 feet north of the southwest corner of sect. 7, T.16S., R.34E. Latitude - 42 degrees, 2 minutes, 17 seconds North; Longitude - 112 degrees, 31 minutes, 47 seconds West.
RANGE IN CHARACTERISTICS:
Thickness of mollic epipedon - 31 to 45 inches
Depth to lime - 16 to 40 inches
Reaction of profile - neutral to moderately alkaline
Average annual soil temperature - 44 to 47 degrees F.
Particle-size control section
Clay content average - 18 to 25 percent (total clay)
Rock fragment content - 10 to 30 percent
A horizon
Value - 4 or 5 dry, 2 or 3 moist
Chroma - 2 or 3 dry or moist
Bt horizons
Value - 4 through 6 dry, 3 or 4 moist
Chroma - 2 or 3 dry or moist
Texture - SIL, GR-L, or GR-SIL
Bk horizons
Hue - 10YR or 7.5YR
Value - 5 through 7 dry, 3 through 6 moist
Chroma - 3 through 5 dry or moist
Texture - GR-SIL, GRV-SIL, GRV-L, GR-L, or GRX-SL
Rock fragments - 15 to 75 percent
2Bk horizons (Present in some pedons)
Hue - 10YR or 7.5YR
Value - 5 through 7 dry, 3 through 5 moist
Texture - GRV-L or GRX-SL
Rock fragments - 35 to 75 percent
COMPETING SERIES: These are the Clegg, Despain, Gross, and Lize series. Clegg soils have less than 5 percent coarse fragments throughout the profile. Despain soils have argillic horizons less than 20 inches thick. Gross soils are moderately deep to bedrock. Lize soils have 25 to 35 percent clay in the control section.
GEOGRAPHIC SETTING: Jensen soils are on level to gently sloping lake terraces, fan terraces, and in drainageways. Slopes range from 0 to 30 percent. Elevation ranges from 4,900 to 5,900 feet. The soil formed in silty alluvium and lacustrine sediments influenced by alluvium. The average annual precipitation ranges from 13 to 18 inches, and the average annual air temperature is 42 to 45 degrees F. The frost-free period is 80 to 100 days.
GEOGRAPHICALLY ASSOCIATED SOILS: Bancroft, Elevator (T), Manila, Hondoho, and Buckboard (T) soils. Bancroft, Elevator, Manila, and Hondoho soils have a mollic epipedon less than 20 inches thick. Buckboard soils have lime deeper than 40 inches. Bancroft, Manila, and Hondoho soils are on mountain sides. Buckboard soils are on lower level lake terraces. Elevator soils are on lake terraces and playas.
DRAINAGE AND PERMEABILITY: Well drained; moderate runoff; moderate permeability.
USE AND VEGETATION: Jensen soils are used for nonirrigated cropland. The vegetation is small grains and alfalfa.
DISTRIBUTION AND EXTENT: Southeastern Idaho. The soils of this series are not extensive.
MLRA SOIL SURVEY REGIONAL OFFICE (MO) RESPONSIBLE: Portland, Oregon
SERIES ESTABLISHED: Oneida County, Idaho, 1994.
REMARKS: Diagnostic horizons and features recognized in this pedon are
Mollic epipedon - the zone from the surface to 38 inches (Ap, A2, Bt1,and Bt2 horizons)
Argillic horizon - the zone from 12 to 38 inches (Bt1 and Bt2 horizons)
Particle-size control section - the zone from 12 to 32 inches (Bt1 and part of the Bt2 horizons)