LOCATION ANTERO COEstablished Series
TAXONOMIC CLASS: Coarse-loamy, mixed, superactive, calcareous, frigid Typic Endoaquepts
TYPICAL PEDON: Antero sandy loam, grassland. (Colors are for dry soil unless otherwise noted.)
A1g--0-7 inches; grayish brown (10YR 5/2) sandy loam, dark grayish brown (10YR 4/2) moist; many medium distinct mottles, yellowish brown (10YR 5/4) moist; moderate fine granular structure; soft, very friable; calcareous; moderately alkaline; clear smooth boundary. (5 to 10 inches thick)
B2g--7 to 22 inches; grayish brown (10YR 5/2) sandy loam, dark grayish brown (10YR 4/2) moist; many medium distinct mottles, yellowish brown (10YR 5/4) and gray (5Y 6/1) moist; weak medium subangular blocky structure; slightly hard, very friable; calcareous; moderately alkaline; gradual wavy boundary. (10 to 20 inches thick)
C1cag-22 to 36 inches; grayish brown (2.5YR 5/2) sandy loam, dark grayish brown (10YR 4/2) moist; many medium distinct mottles, yellowish brown (10YR 5/4) and gray (5Y 6/1) moist; weak medium subangular blocky structure; slightly hard, very friable; calcareous; moderately alkaline; gradual wavy boundary. (10 to 20 inches thick)
C2g--36 to 60 inches; grayish brown (10YR 5/2) sandy loam, dark grayish brown (10YR 4/2) moist; many medium distinct mottles, yellowish brown (10YR 5/6) and gray (5Y 6/1) moist; massive; slightly hard, very friable; calcareous; moderately alkaline.
TYPE LOCATION: Chaffee County, Colorado; 170 feet north of the SE corner of Sec. 27, T. 15 S., R. 78 W.
RANGE IN CHARACTERISTICS: The Antero soils typically are calcareous throughout but depth to uniformly calcareous material ranges from 0 to 10 inches. Exchangeable sodium ranges from 0 to 15 percent in most of the control section, and there are no subhorizons more than 4 inches thick above a depth of 20 inches that exceed 15 percent. Depth to continuous concentrated horizons of visible secondary calcium carbonate and/or sulfate ranges from 12 to 40 inches. The control section is usually sandy loam but ranges from 5 to 80 percent clay, 5 to 40 percent silt, and 50 to 80 percent sand with more than 35 percent fine or coarser sand. Loamy fine sand or coarser textures are excluded from the above range. Rock fragments range from 0 to 15 percent by volume in a major part of the control section and are typically less than 3 inches in diameter.
The A horizon has hue of 2.5Y through 7.5YR, value of 4 through 7 dry, 3 through 6 moist, and chroma of 1 through 4. It ranges from mildly to strongly alkaline.
The B2g horizon has hue of 2.5Y through 7.5YR, value of 5 through 7 dry, 4 through 6 moist, and chroma of 0 through 2. It is moderately or strongly alkaline. The Ccag horizon has hue of 5Y through 7.5YR. It ranges from moderately to very strongly alkaline and has 3 to 14 percent calcium carbonate equivalent of the fine earth.
COMPETING SERIES: These are the Cruickshank and Girardot series. Cruickshank soils have mean annual soil temperature warmer than 47 degrees F. Girardot soils have mean summer soil temperature colder than 54 degrees F and have medium to moderately fine textured control sections with more than 18 percent clay.
GEOGRAPHIC SETTING: The Antero soils are on alluvial fans and terraces. Slopes gradients range from 0 to 6 percent. The soils formed in alluvial parent materials derived from a variety of rock sources. At the type location the average annual precipitation is 12 inches, with peak periods of precipitation in the spring and summer. The mean annual temperature is 43 degrees F, and the mean summer temperature is 61 degrees F.
GEOGRAPHICALLY ASSOCIATED SOILS: These are the Collegiate and Cotopaxi soils. Collegiate soils have sandy-skeletal substratums and mollic epipedons. Cotopaxi soils have sandy control sections and are well drained.
DRAINAGE AND PERMEABILITY: Poorly to somewhat poorly drained; slow runoff; rapid permeability above the fluctuating water table.
USE AND VEGETATION: These soils are used principally as irrigated hay meadow and as native pastureland. Native vegetation is water tolerant grasses and sedges.
DISTRIBUTION AND EXTENT: High mountain valleys of central Colorado. This series is of moderate extent.
MLRA SOIL SURVEY REGIONAL OFFICE (MO) RESPONSIBLE: Bozeman, Montana
SERIES ESTABLISHED: Chaffee County, Colorado, 1974.
REMARKS: Last updated by the state 9/74.