LOCATION HAMPSON IDEstablished Series
TAXONOMIC CLASS: Coarse-silty, mixed, superactive, frigid Fluventic Haploxerolls
TYPICAL PEDON: Hampson silt loam - cultivated. (Colors are for dry soil unless otherwise stated.)
Ap--0 to 7 inches; dark gray (10YR 4/1) silt loam, very dark brown (10YR 2/2) moist; moderate fine and very fine granular structure; slightly hard, very friable, slightly sticky and slightly plastic; many very fine roots; many fine interstitial pores; slightly acid (pH 6.4); abrupt smooth boundary. (5 to 9 inches thick)
A12--7 to 11 inches; gray (10YR 5/1) silt loam, very dark brown (10YR 2/2) moist; weak medium and fine subangular blocky structure; hard, very friable, slightly sticky and slightly plastic; many very fine roots; many very fine tubular pores; slightly acid (pH 6.4); clear wavy boundary. (0 to 10 inches thick)
A13--11 to 18 inches; grayish brown (10YR 5/2) silt loam, very dark grayish brown (10YR 3/2) moist; weak medium prismatic structure parting to weak medium and fine subangular blocky; hard, very friable, slightly sticky and slightly plastic; many very fine roots; many very fine and common medium tubular pores, few coarse tubular pores vertically oriented; neutral (pH 6.6); clear wavy boundary. (0 to 10 inches thick)
A14--18 to 28 inches; light brownish gray (10YR 6/2) silt loam, very dark grayish brown (10YR 3/2) moist; weak medium prismatic structure; hard, very friable, slightly sticky and slightly plastic; common very fine roots; many very fine and common medium tubular pores, few coarse tubular pores vertically oriented; neutral (pH 6.8); gradual wavy boundary. (5 to 15 inches thick)
C1--28 to 36 inches; light gray (10YR 7/2) loam, brown (10YR 4/3) moist; massive; hard, very friable, slightly sticky and slightly plastic; few very fine roots; many very fine and common medium tubular pores, few coarse tubular pores vertically oriented; neutral (pH 6.8); clear wavy boundary. (8 to 20 inches thick)
C2--36 to 60 inches; light brownish gray (10YR 6/2) silt loam, dark grayish brown (10YR 4/2) moist; many medium distinct mottles; massive; very hard, friable, sticky and plastic; many very fine tubular pores, few coarse tubular pores vertically oriented; neutral (pH 6.6).
TYPE LOCATION: Latah County, Idaho; about 1,800 feet west and 360 feet south of the northeast corner of section 8, T. 41 N., R. 4 W.
RANGE IN CHARACTERISTICS: The mean annual soil temperature is 45 to 47 degrees F., and the mean summer soil temperature at a depth of 20 inches is 59 to 64 degrees F., if without an O horizon. The soils are usually moist but are dry between depths of 4 and 12 inches for 45 to 60 consecutive days in late summer. The mollic epipedon is 10 to 20 inches thick. Texture between depths of 10 and 40 inches is silt loam or loam and 10 to 18 percent clay and less than 15 percent fine sand or coarser. The soils are slightly acid or neutral throughout.
The A horizon has value of 4 or 5 above a depth of 10 inches; and value of 4, 5, or 6 below 10 inches; chroma is 1 or 2.
The C horizon has value of 6 or 7 and chroma of 2 or 3.
COMPETING SERIES: There are no other series in this family.
GEOGRAPHIC SETTING: The soils are on valley floors. Slope is 0 to 3 percent. Elevation is about 2,500 feet. The soils formed in alluvium from mixed sources. The mean annual precipitation ranges from 23 to 28 inches. The frost-free period ranges from 100 to 120 days.
GEOGRAPHICALLY ASSOCIATED SOILS: These are the Santa, Southwick, and Taney soils. These are upland soils formed in loess and have an albic horizon and an argillic horizon.
DRAINAGE AND PERMEABILITY: Moderately well drained; slow runoff; moderate permeability.
USE AND VEGETATION: Used for hayland, pastureland, and cropland.
DISTRIBUTION AND EXTENT: Latah County, Idaho. The series is of small extent.
MLRA OFFICE RESPONSIBLE: Portland, Oregon
SERIES ESTABLISHED: Latah County, Idaho, 1979.