LOCATION WITHERS IDEstablished Series
TAXONOMIC CLASS: Fine-loamy over sandy or sandy-skeletal, mixed, superactive, frigid Aquic Haploxerolls
TYPICAL PEDON: Withers silty clay loam, pasture. (Colors are for dry soil unless otherwise noted.)
A1--0 to 7 inches; grayish brown (10YR 5/2) silty clay loam, very dark grayish brown (10YR 3/2) moist; moderate fine and very fine granular structure; slightly hard, friable, slightly sticky and plastic; many very fine and fine roots; many very fine interstitial pores; slightly calcareous; moderately alkaline (pH 8.0); gradual smooth boundary. (7 to 12 inches thick)
B21--7 to 16 inches; grayish brown (10YR 5/2) silty clay loam,; very dark grayish brown (10YR 3/2) moist; moderate medium and fine subangular blocky structure; hard, friable, sticky and plastic; many medium and fine roots; few medium tubular pores; slightly calcareous; moderately alkaline (pH 8.0); gradual wavy boundary. (4 to 15 inches thick)
B22--16 to 26 inches; pale brown (10YR 6/3) silty clay loam, brown (10YR 5/3) moist; common fine faint yellowish brown (10YR 5/4) moist mottles; strong fine and very fine subangular blocky structure; hard, friable, sticky and plastic; common very fine roots; many very fine and common fine tubular pores; common thin and very thin clay films on ped faces; slightly calcareous; mildly alkaline (pH 7.8); abrupt wavy boundary. (6 to 15 inches thick)
IIC1--26 to 36 inches; pale brown (10YR 6/3) very gravelly loamy sand; brown (10YR 4/3) moist; single grained; loose; many very fine and fine interstitial pores; slightly calcareous; mildly alkaline (pH 7.6); clear wavy boundary. (5 to 15 inches thick)
IIIC2--36 to 60 inches; sand and gravel with 15 percent cobbles.
TYPE LOCATION: Madison County, Idaho; just north of potato processing plant; 60 feet south and 100 feet west of the northeast corner of section 8, T.7N., R.40E.
RANGE IN CHARACTERISTICS: The mean annual soil temperature ranges from 41 to 47 degrees F., and the mean summer temperature at a depth of 20 inches ranges from 60 to 65 degrees F. The soils are saturated at some depth between 24 and 48 inches for short periods in the spring and early summer. The total cumulative time is more than 90 days. The soils between are usually moist and between depths of 4 and 12 inches become dry for at least 45 consecutive days in mid and late summer, unless irrigated. The sola is 17 to 42 inches thick. Between depth of 10 inches and the underlying sand layers, the soil is silty clay loam or clay loam containing 27 to 35 percent clay, more than 15 percent particles coarser than very fine sand, and less than 15 percent coarse fragments by weighted average.
The A1 or Ap horizon has value of 4 or 5 dry, 2 or 3 moist, and chroma of 1 or 2.
The lower part of the B2 horizon has value of 5 or 6 dry, 4 or 5 moist, and chroma of 2 or 3. The B horizon has weak or moderate subangular blocky structure. Depth to mottles ranges from 18 to 27 inches.
COMPETING SERIES: These are the Annis, Blackfoot, and Labenzo series in other families. Annis and Blackfoot soils are more than 40 inches deep to sand and gravel. Blackfoot and Labenzo soils have a control section that contains more than 15 percent particles larger than very fine sand.
GEOGRAPHIC SETTING: Withers soils are on depressional areas of low terraces, alluvial bottoms, and floodplains, and have slopes of 0 to 2 percent. The soils formed in mixed alluvial material from weathered basalt, granite and some sedimentary rocks. Elevations are 4,500 to 5,500 feet. The mean annual precipitation is 8 to 12 inches. The mean annual soil temperature is 41 to 45 degrees F. The frost free season is 100 to 110 days.
GEOGRAPHICALLY ASSOCIATED SOILS: These are the competing Annis, Blackfoot, and Labenzo soils.
DRAINAGE AND PERMEABILITY: Somewhat poorly drained; very slow runoff; moderately slow permeability. These soils are occasionally flooded. Depth to seasonal water table ranges from 24 to 48 inches, it is above 30 inches for only short periods.
USE AND VEGETATION: Used mainly for alfalfa hay, small grains, and pasture.
DISTRIBUTION AND EXTENT: Southeastern Idaho. The series is inextensive.
MLRA SOIL SURVEY REGIONAL OFFICE (MO) RESPONSIBLE: Portland, Oregon
SERIES ESTABLISHED: Madison County, Idaho, 1977.
REMARKS: A previous draft (7/75) classified this series on the basis of an argillic horizon. The series is redefined.