LOCATION CHATCOLET IDEstablished Series
TAXONOMIC CLASS: Ashy over loamy, glassy over mixed, superactive Alfic Vitricryands
TYPICAL PEDON: Chatcolet ashy silt loam, basement excavation. (Colors are for dry soil unless otherwise noted.)
Ap--0 to 8 inches; brown (10YR 5/3) ashy silt loam, brown (7.5YR 4/2) moist; weak medium platy structure that parts to moderate fine and medium granular structure; soft, friable, slightly sticky snd slightly plastic; many very fine and fine roots; many very fine and fine tubular pores; 1 percent medium gravel; neutral (pH 6.6); abrupt wavy boundary. (0 to 8 inches thick)
Bw1--8 to 16 inches; yellowish brown (10YR 5/4) ashy silt loam, brown (7.5YR 4/4) moist; weak coarse prismatic structure; hard, friable, slightly sticky and slightly plastic; many very fine and fine roots; many very fine, fine and medium tubular pores; about 1 percent medium gravel; neutral (pH 6.6) clear wavy boundary. (8 to 12 inches thick)
Bw2--16 to 24 inches; pale brown (10YR 6/3) ashy silt loam, dark yellowish brown (10YR 4/4) moist; weak coarse prismatic structure that parts to weak coarse subangular blocky structure; hard, friable, slightly sticky and slightly plastic; many very fine and fine roots; many very fine, fine and medium tubular pores; 5 percent medium gravel; slightly acid (pH 6.4); clear wavy boundary. (8 to 16 inches thick)
2Bt1--24 to 30 inches; pale brown (10YR 6/3) silt loam, dark yellowish brown (10YR 4/4) moist; weak medium prismatic structure that parts to moderate medium subangular blocky structure; hard, friable, slightly sticky and slightly plastic; many very fine and fine roots; many very fine, fine and medium tubular pores; faint patchy clay films on clayey bands that occupy 50 percent of the horizon; many distinct black stains; about 2 percent medium gravel; neutral (pH 6.8); clear wavy boundary. (6 to 8 inches thick)
2Bt2--30 to 60 inches; pale brown (10YR 6/3) silty clay loam, olive brown (2.5Y 4/4) moist; weak medium prismatic structure; very hard, firm, moderately sticky and moderately plastic; many very fine, fine and medium tubular pores; prominent patchy clay films on clayey bands that occupy 25 percent of the horizon; many prominent black stains; about 1 percent medium gravel; neutral (pH 7.0); gradual wavy boundary.
TYPE LOCATION: Benewah County, Idaho; about 1.5 miles south of St. Maries, Idaho; center of NE1/4 of sec. 36, T.46N., R.2W.
RANGE IN CHARACTERISTICS: The mean annual soil temperature ranges from 40 to 44 degrees F. The mean summer soil temperature at a depth of 20 inches ranges from 45 to 47 degrees F., with an O horizon. The solum is more than 60 inches deep. In undisturbed areas, the pedons have a very thin layer of recent volcanic ash between the O and Bw horizons.
The Ap horizon has hue of l0YR or 7.5YR, value of 5 through 7 dry, 4 or 5 moist and chroma of 2 through 4. It is ashy silt loam or ashy loam. This horizon has weak or moderate granular, subangular blocky or platy structure.
The Bw horizon has hue of l0YR, 7.5YR or 5YR, value of 5 through 7 dry, 3 through 5 moist and chroma of 3 or 4. It is ashy silt loam or ashy loam. This horizon has weak or moderate prismatic or subangular blocky structure.
The 2Bt horizon has hue of l0YR or 2.5Y, value of 5 through 7 dry, 3 through 5 moist, and chroma of 3 or 4. It is silt loam, loam, silty clay loam, or clay loam and some profiles are gravelly. Clay films range from faint to prominent.
COMPETING SERIES: There are no competing series.
GEOGRAPHIC SETTING: Chatcolet soils are on glacio-lacustrine terraces. Slopes range from 3 to 40 percent and are dominantly 5 to 20 percent. The soils formed in volcanic ash over glacio-lacustrine material. Elevations range from 2,300 to 2,800 feet. The mean annual precipitation is 25 to 30 inches including 5 to 8 feet of snow. The frost-free season is 70 to 90 days.
GEOGRAPHICALLY ASSOCIATED SOILS: These are the Dorb soils. Dorb soils have more than 35 percent rock fragments in the control section.
DRAINAGE AND PERMEABILITY: Moderately well drained; rapid runoff; moderately slow permeability.
USE AND VEGETATION: The main use is for urban and recreational homesites. Some areas are used for pasture and woodland. Overstory native vegetation is mainly western hemlock, western redcedar, western white pine, grand fir, western larch, Douglas-fir, lodgepole pine and ponderosa pine. The under-story is Myrtle pachistima, queencup beadlily, oak fern, longtube twinflower, oneleaf foamflower and mountain blueberry.
DISTRIBUTION AND EXTENT: Benewah, Kootenai and Shoshone Counties in northern Idaho. The series is inextensive.
MLRA OFFICE RESPONSIBLE: Bozeman, Montana
SERIES ESTABLISHED: Benewah County, Idaho, 1975.