LOCATION IYERS CO+UT WYEstablished Series
TAXONOMIC CLASS: Fine, smectitic Ustic Haplocryepts
TYPICAL PEDON: Iyers silty clay loam- Range. (Colors are for dry soil unless otherwise noted.)
A--0 to 6 inches; light brownish gray (2.5Y 6/2) silty clay loam, dark grayish brown (2.5Y 4/2) moist; weak medium subangular blocky structure parting to moderate fine granular; slightly hard, friable, slightly sticky and slightly plastic; strongly effervescent; moderately alkaline; clear smooth boundary. (2 to 8 inches thick.)
AC--6 to 15 inches; light brownish gray (2.5Y 6/2) clay, grayish brown (2.5Y 5/2) moist; weak coarse subangular blocky structure parting to weak medium subangular blocky; hard, firm, very sticky and very plastic; few small shale chips; violently effervescent; moderately alkaline; gradual smooth boundary. (4 to 14 inches thick.)
C--15 to 33 inches; light brownish gray (2.5Y 6/2) clay, grayish brown (2.5Y 5/2) moist; weak coars subangular blocky structure; hard, firm, very sticky and very plastic; violently effervescent; moderately alkaline; abrupt smooth boundary. (14 to 20 inches thick).
Cr--33 inches; weathered dark calcareous shale.
TYPE LOCATION: Eagle County, Colorado; near Eiby Creek; 1,200 feet north and 900 feet east of the southwest corner of Sec. 11, T. 4 S., R. 84 W.; Eagle USGS quad; lat. 39 degrees 42 minutes 52 seconds N. and long. 106 degrees 47 minutes 00 seconds W., NAD 27.
RANGE IN CHARACTERISTICS: The mean annual soil temperature ranges from 38 to 42 degrees F. and the mean summer soil temperature ranges from 52 to 57 degrees F. These soils are calcareous throughout. Depth to the paralithic contact ranges from 20 to 40 inches. The particle size control section is clay loam or light clay but ranges from 35 to 50 percent clay. Rock fragments range from 0 to 15 percent and are mainly 1/4 to 10 inches in diameter.
The A horizon has a hue of 5Y through 7.5YR, value of 5 through 7, 3 through 6 moist, and chroma of 1 through 4. When the soil has dry value of 5 or darker and moist value of 3.5 or darker, the A horizon is too thin to qualify for a mollic epipedon. It is mildly or moderately alkaline.
The AC horizon has hue of 5Y through 7.5YR, value of 5 through 7, 4 through 6 moist and chroma of 2 through 4. Reaction is mildly or moderately alkaline.
The C horizon has hue of 5Y through 7.5YR. It is mildly or moderately alkaline.
COMPETING SERIES: There are currently no competing series in this family.
GEOGRAPHIC SETTING: Iyers soils are on hills, ridges, and mountain side slopes. Slopes range from 2 to 65 percent. The soil formed in calcareous materials weathered from sedimentary rocks. At the type location, the mean annual precipitation is 16 to 20 inches. The mean annual temperature is 36 to 40 degrees F., and the frost-free season is 60 to 90 days. Elevation ranges from 8,000 to 10,000 feet.
GEOGRAPHICALLY ASSOCIATED SOILS: These are Forsey, Cochetopa, and Antrobus soils. These soils all have mollic epipedons. Forsey and Antrobus series have loamy- skeletal particle size control sections. In addition, Forsey and Cochetopa soils have argillic horizons.
DRAINAGE AND PERMEABILITY: Well drained; slow to rapid runoff; slow permeability.
USE AND VEGETATION: These soils are used as native rangeland. Principal vegetation is wheatgrass, muttongrass, rabbitbrush, and sagebrush.
DISTRIBUTION AND EXTENT: Intermountain areas of northwest Colorado and possibly adjacent areas of Utah. The series is of small extent.
MLRA SOIL SURVEY REGIONAL OFFICE (MO) RESPONSIBLE: Bozeman, Montana
SERIES ESTABLISHED: Eagle County, Colorado; Aspen-Gypsum Soil Survey Area, 1984.