LOCATION BOCK IDEstablished Series
TAXONOMIC CLASS: Coarse-loamy, mixed, superactive, frigid Calcidic Haploxerolls
TYPICAL PEDON: Bock loam, pasture. (Colors are for dry soil unless otherwise noted.)
Ap--0 to 5 inches; grayish brown (10YR 5/2) loam, very dark grayish brown (10YR 3/2) moist; moderate medium platy structure parting to moderate very fine and fine granular; slightly hard, friable, slightly sticky and slightly plastic; many very fine and fine roots; many very fine irregular pores; slightly effervescent; slightly alkaline (pH 7.8); gradual smooth boundary. (0 to 10 inches thick)
A--5 to 10 inches; grayish brown (10YR 5/2) loam, very dark grayish brown (10YR 3/2) moist; weak medium platy structure parting to moderate fine and medium subangular blocky and weak fine and medium granular; hard, friable, slightly sticky and slightly plastic; common very fine and fine roots; common very fine and fine tubular pores; slightly alkaline (pH 7.8); gradual wavy boundary. (4 to 8 inches thick)
Bw--10 to 15 inches; brown (10YR 5/3) pale brown (10YR 6/3, crushed) loam, dark brown (10YR 4/3) moist; weak fine and medium subangular blocky structure; hard, friable, slightly sticky and slightly plastic; common very fine and fine roots; common very fine and fine tubular pores; slightly alkaline (pH 7.8); clear wavy boundary. (4 to 14 inches thick)
Bk1--15 to 26 inches; light gray (10YR 7/2) loam, dark grayish brown (10YR 4/2) moist; weak fine and medium subangular blocky structure; hard, friable, slightly sticky and slightly plastic; common very fine and fine roots; common very fine and fine tubular pores; violently effervescent; common fine lime veins and spots; moderately alkaline (pH 8.0); gradual wavy boundary. (0 to 18 inches thick)
Bk2--26 to 35 inches; light brownish gray (10YR 6/2) loam, dark grayish brown (10YR 4/2) moist; weak medium subangular blocky structure; hard, friable, nonsticky and slightly plastic; common very fine and fine roots; common very fine and fine tubular pores; few cicada krotovinas; violently effervescent, common veins and spots of lime; moderately alkaline (pH 8.0); gradual wavy boundary. (5 to 14 inches thick)
Bk3--35 to 47 inches; light brownish gray (10YR 6/2) fine sandy loam, dark grayish brown (10YR 4/2) moist; massive; slightly hard, very friable, nonsticky and nonplastic; common very fine and fine roots; common very fine and fine tubular pores; few yellowish brown (10YR 5/4) root stains; strongly effervescent, very few lime veins; slightly alkaline (pH 7.8); abrupt wavy boundary. (10 to 20 inches thick)
2Bk4--47 to 60 inches; light brownish gray (10YR 6/2) very gravelly coarse sand; about 15 percent of the pebbles are black or very dark gray; single grain; loose; few very fine and fine roots; many very fine irregular pores; 60 percent pebbles, mostly quartzite; strongly effervescent, pebbles slightly lime-coated on lower side; slightly alkaline (pH 7.6).
TYPE LOCATION: Bingham County, Idaho; 4 miles north of Blackfoot on a level terrace; 1,450 feet east and 600 feet south from the NW corner of sec. 21, T. 2S., R. 35 E.
RANGE IN CHARACTERISTICS:
Average annual soil temperature - 41 to 47 degrees F.
Average summer soil temperature - 60 to 66 degrees F.
Mollic epipedon - 7 to 12 inches thick
Depth to calcic horizon - 12 to 24 inches
Particle-size control section:
Percent clay - 14 to 18 percent
Rock fragments - 0 to 35 percent
A horizon:
Value - 4 or 5 dry, 2 or 3 moist
Chroma - 2 or 3 dry or moist
Reaction - neutral to moderately alkaline
The upper few inches is effervescent in some pedons.
Bw horizon:
Value - 5 or 6 dry, 4 or 5 moist
Chroma - 2 to 4 dry or moist
Texture - L, FSL, SIL, or GR-L
Reaction - mildly or moderately alkaline
Bk and 2Bk horizons:
Value - 5 through 8 dry, 4 through 6 moist
Chroma - 2 or 3 dry or moist
Calcium carbonate equivalent - 5 to 25 percent
Stratification with moderately coarse textures occurs below 20 inches in some pedons.
COMPETING SERIES: These are the Waddoups and Wapello series. Waddoups and Wapello soils both contain free carbonates throughout and lack a cambic horizon.
GEOGRAPHIC SETTING: The soils are on stream terraces and alluvial fans at elevations of 3,800 to 6,600 feet. Slopes range from 0 to 10 percent. The soils formed in medium-textured alluvium, dominantly from quartzite and sedimentary rock sources. In places, the upper part is eolian deposits. The climate is semiarid and has dry summers. Average annual precipitation is 10 to 13 inches, including 2 to 5 feet of snowfall. Frost-free period is 70 to 126 days. Average annual air temperature is 39 to 45 degrees F.
GEOGRAPHICALLY ASSOCIATED SOILS: These are the Bannock, Hayeston, Packham and Stan soils. Bannock soils have strongly contrasting particle-size control sections. Hayeston soils lack a mollic epipedon and a calcic horizon. Packham soils have a loamy-skeletal control section. Stan soils are calcareous throughout.
DRAINAGE AND PERMEABILITY: Well drained; slow to medium runoff; moderate permeability in the upper part and very rapid permeability in the lower part.
USE AND VEGETATION: Mostly cultivated under irrigation for hay, pasture, potatoes, sugar beets, and small grains. The principal native plants are big sagebrush, bluebunch wheatgrass, Sandberg bluegrass, cheatgrass, and squirreltail.
DISTRIBUTION AND EXTENT: The series is moderately extensive in the terraces of the Upper Snake River Valley and the tributary valleys in eastern Idaho.
MLRA SOIL SURVEY REGIONAL OFFICE (MO) RESPONSIBLE: Portland, Oregon
SERIES ESTABLISHED: Bingham County, Idaho, 1972.
REMARKS: Diagnostic horizons and features recognized in this pedon are:
Mollic epipedon - the zone from the surface of the soil to 10 inches (Ap and A horizons).
Cambic horizon - the zone from 10 to 15 inches (Bw horizon).
Calcic horizon - the zone of calcium carbonate accumulation from 15 to 35 inches. (Bk1 and Bk2 horizons).
Particle-size control section - the zone from 10 to 40 inches (Bw, Bk1, Bk2 and part of the C1 horizons).