LOCATION MCCAMMON IDEstablished Series
TAXONOMIC CLASS: Fine-loamy, mixed, superactive, frigid Calcidic Haploxerolls
TYPICAL PEDON: McCammon loam - pasture. (Colors are for dry soil unless otherwise noted.)
Ap--0 to 7 inches; grayish brown (10YR 5/2) loam, very dark grayish brown (10YR 3/2) moist; moderate medium granular structure; slightly hard, friable, slightly sticky, slightly plastic; common very fine and fine roots; many very fine interstitial pores; mildly alkaline (pH 7.8); gradual smooth boundary. (0 to 9 inches thick)
A12--7 to 14 inches; grayish brown (10YR 5/2) loam, very dark grayish brown (10YR 3/2) moist; moderate medium subangular blocky structure that parts to moderate medium granular structure; slightly hard, friable, slightly sticky, slightly plastic; common very fine and fine roots; many very fine and fine tubular pores; mildly alkaline (pH 7.6); clear wavy boundary. (5 to 10 inches thick)
B2--14 to 19 inches; pale brown (10YR 6/3) heavy loam, dark brown (10YR 4/3) moist; moderate medium subangular blocky structure; hard, firm, sticky, plastic; common very fine and fine roots; many very fine and fine tubular pores; mildly alkaline (pH 7.6); clear wavy boundary. (4 to 10 inches thick)
Cca--19 to 30 inches; very pale brown (10YR 7/3) loam, brown (10YR 4/3) moist; weak medium subangular blocky structure; slightly hard, friable, slightly sticky, slightly plastic; few very fine and fine roots; many very fine and fine tubular pores; moderately calcareous; moderately alkaline (pH 8.0); abrupt wavy boundary. (10 to 20 inches thick)
IIR--30 to 35 inches; black (N 2/ ) basalt bedrock with calcium carbonate coating on upper surfaces.
TYPE LOCATION: Bingham County, Idaho; about 3 miles west and 1 mile north of Riverside; 1,950 feet east and 800 feet south of the NW corner of sec. 32, T.2S., R.34E.
RANGE IN CHARACTERISTICS: The mean annual soil temperature ranges from 41 to 47 degrees F., and the mean summer temperature at depth of 20 inches ranges from 60 to 66 degrees F. Unless irrigated, the 4- to 12-inch moisture control section is dry in all parts for 60 to 90 consecutive days within the 3-month period following the summer solstice in more than 7 years out of 10 and is moist in all parts for 60 to 90 consecutive days within the 3-month period following the winter solstice. Also, this section is dry in all parts more than half the time (cumulative) that the soil temperature at 20 inches is above 41 degrees F. Basalt bedrock is within 40 inches of the surface, but its upper boundary is commonly below 28 inches. The solum is 14 to 22 inches thick. The textural control section contains 18 to 27 percent clay, more than 15 percent particles coarser than very fine sand, and less than 15 percent coarse fragments. The hue of the soil is 10YR in most pedons, but it is 2.5Y in some. The A horizon is 8 to 12 inches thick. It has chroma of 2 or 3, and organic matter content of 1.5 to 2 percent. This horizon is noncalcareous and is neutral or mildly alkaline. The B horizon has value of 5 or 6 dry and 4 or 5 moist and chroma of 2 or 3. It is dominantly loam but ranges to silt loam or light clay loam. This horizon has weak to moderate, fine to medium subangular blocky structure. It is noncalcareous or slightly calcareous and mildly or moderately alkaline. The Cca horizon contains 10 to 15 percent calcium carbonate and has its upper boundary at depths of 15 to 25 inches.
COMPETING SERIES: These are the Bock, Fanu, Usher and Wahtigup series. Bock, Fanu and Wahtigup soils lack bedrock at depths of 40 inches or less. Also, Bock soils have less than 18 percent clay in the control section and Wahtigup soils are calcareous throughout. Usher soils have a mean annual temperature warmer than 47 degrees F.
GEOGRAPHIC SETTING: The McCammon soils are on level to strongly sloping terraces and uplands at elevations of 4,200 to 5,900 feet. Slopes range from 0 to 30 percent. The soils formed mainly in medium-textured alluvium or eolian deposits over basalt bedrock. The material is dominantly from quartzite and sedimentary rock sources but contains some rhyolitic, basaltic, and granitic materials. The climate is semiarid and has dry summers. Mean annual precipitation is 10.5 to 13 inches, including 2.5 to 5 feet of snowfall. Average freeze-free period is 94 to 126 days.
PRINCIPAL ASSOCIATED SOILS: These are the Bannock, Hayeston, Packham, and Stan soils and the competing Bock soils. Bannock and Packham soils have coarse sand and gravel at depths of less than 40 inches. Stan soils are moderately coarse textured between depths of 10 and 20 inches or deeper. Hayeston soils lack a mollic epipedon and are underlain by sand and gravel at depths of less than 40 inches.
DRAINAGE AND PERMEABILITY: Well-drained; slow or medium runoff; moderate permeability in the A, B, and Cca horizons, and very slow in the underlying basalt.
USE AND VEGETATION: Mostly cultivated under irrigation for hay, pasture, potatoes, sugar beets and small grains. The natural vegetation is mainly big sagebrush, bluebunch wheatgrass, Sandberg blue grass, cheatgrass, and squirreltail.
DISTRIBUTION AND EXTENT: The series is moderately extensive in the Upper Snake River Valley and the tributary valleys in eastern Idaho.
MLRA SOIL SURVEY REGIONAL OFFICE (MO) RESPONSIBLE: Portland, Oregon
SERIES ESTABLISHED: Bannock County (Portneuf Area), Idaho, 1918.
REMARKS: The soils were classified formerly as Brown soils.
OSED scanned by SSQA. Last revised by state on 12/71.