LOCATION SKYWAY             CO+UT
Established Series
Rev. GB/JPP
02/1999

SKYWAY SERIES


The Skyway series consists of moderately deep, well drained soils that formed in moderately coarse textured, noncalcareous sediments weathered from sandstone, andesite, quartz latite, and rhyolite. Skyway soils are on mesas, mountain side slopes, plateaus, and foot slopes. Slopes are 1 to 75 percent. Mean annual precipitation is about 22 inches and the mean annual temperature is about 40 degrees F.

TAXONOMIC CLASS: Coarse-loamy, mixed, superactive Pachic Haplocryolls

TYPICAL PEDON: Skyway fine sandy loam - grassland. (Colors are for dry soil unless otherwise noted.)

A1--0 to 5 inches; grayish brown (10YR 5/2) fine sandy loam, very dark brown (10YR 2/2) moist; weak medium granular structure; soft, very friable, nonsticky and nonplastic; neutral; clear wavy boundary. (5 to 12 inches thick)

A2--5 to 12 inches; grayish brown (10YR 5/2) fine sandy loam, very dark grayish brown (10YR 3/2) moist; moderate medium granular structure; soft, very friable, slightly sticky and slightly plastic; neutral; clear wavy boundary. (6 to 24 inches thick)

A3--12 to 20 inches; brown (10YR 5/3) fine sandy loam, dark brown (10YR 3/3) moist; weak medium subangular blocky structure; slightly hard, very friable, slightly sticky and slightly plastic; neutral; gradual wavy boundary. (0 to 10 inches thick)

AC--20 to 26 inches; very pale brown (10YR 7/3) fine sandy loam, brown (10YR 4/3) moist; weak medium subangular blocky structure; soft, very friable, slightly sticky and slightly plastic; neutral; clear wavy boundary. (0 to 8 inches thick)

C--26 to 31 inches; very pale brown (10YR 7/3) gravelly sandy loam, brown (10YR 5/3) moist; massive; soft, very friable, slightly sticky and slightly plastic; 20 percent pebbles, 10 percent cobbles; neutral; abrupt wavy boundary. (0 to 20 inches thick)

R--31 inches; hard sandstone bedrock.

TYPE LOCATION: Moffat County, Colorado; about 15 miles southeast of Maybell, about 1,000 feet north and 500 feet east of the southwest corner of Sec. 19, T. 4 N., R. 94 W. U.S.G.S. Easton Gulch quad.; Latitude: 40 degrees, 17 minutes, 51 seconds N.; Longitude: 107 degrees, 59 minutes, 17 seconds W.

RANGE IN CHARACTERISTICS: Mean annual soil temperature ranges from 39 to 47 degrees F., and mean summer soil temperature ranges from 52 to 59 degrees F. The mollic epipedon is 16 to 40 inches thick. Depth to the lithic contact ranges from 20 to 40 inches. The organic carbon content of the mollic epipedon is .8 to 6 percent and decreases uniformly with depth. Conductivity is usually less than 1 millimho, calcium carbonate equivalent is less than 1 percent, and exchangeable sodium percentage less than 1. The soil is 90 to 100 percent base-saturated. In some pedons a cambic horizon having brighter chroma and moderate grades of structure exists below the mollic epipedon. The series control section is loam, fine sandy loam, or sandy loam with 10 to 18 percent clay. Rock fragments are commonly less than 15 percent, but range from 0 to 35 percent, and tend to increase with depth.

The A horizon has hue of 2.5Y through 7.5YR, value of 3 through 5 dry, 2 or 3 moist, and chroma of 1 through 3. It is slightly acid through slightly alkaline. It usually has granular or crumb primary structure but is subangular blocky in some pedons, particularly in the lower part. It is soft to slightly hard. The lower part of the horizon may have brighter chroma, higher value, or redder hue than the upper part.

The C horizon, when present, has hue of 2.5Y through 7.5YR, value of 6 or 7 dry, 5 or 6 moist, and is lithochromic. It is slightly acid through slightly alkaline.

COMPETING SERIES: These are the Aycab (NV), Cindersprings (ID), Coutis (WY), Earcree (ID), Foxvire (NV), Gardner's Fork (UT), Hailman (UT), Moonlight (ID), Naz (ID), Razorba (CO), Shook (MT), Taral (AK), and Tosp (NV) series. Cindersprings, Coutis, Earcree, Foxvire, Gardner's Fork, Hailman, Moonlight, Naz, Razorba, Taral, and Tosp soils lack a lithic contact above 40 inches. Shook soils have more than 35 percent rock fragments in the lower part of the series control section and have a high proportion of medium and coarse angular sand. Aycab soils have a paralithic contact at 24 to 40 inches.

GEOGRAPHIC SETTING: Skyway soils are on upland mesas, plateaus, mountain slopes, ridgetops, and foot slopes. Elevation generally ranges from 7,000 to 10,500 feet. In Idaho, elevation ranges from 5,500 to 6,300 feet. Mean annual temperature is 37 to 40 degrees F., and mean summer temperature ranges from 50 to 56 degrees F. Average annual precipitation ranges from 18 to 35 inches with peak periods of precipitation during the winter and early spring. Slopes range from 1 to 75 percent. The soils formed in moderately coarse textured, noncalcareous sediments weathered from sandstone, andesite, quartz latite, and rhyolite, and may have some aeolian influence in the upper part of some pedons.

GEOGRAPHICALLY ASSOCIATED SOILS: These are the Bangston and Splitro soils. Bangston soils have textures of sand to loamy sand in the 10 to 40 inch texture control section. Splitro soils have mollic epipedons less than 16 inches thick and overlie sandstone bedrock at depths of 10 to 20 inches.

DRAINAGE AND PERMEABILITY: Well drained; slow runoff; moderately rapid permeability.

USE AND VEGETATION: These soils are used as native pastureland. Native vegetation is Thurber's fescue, nodding brome, Idaho fescue, sagebrush, snowberry, aspen peavine, and Gambel oak.

DISTRIBUTION AND EXTENT: The western slope of Colorado. The series is of moderate extent.

MLRA SOIL SURVEY REGIONAL OFFICE (MO) RESPONSIBLE: Bozeman, Montana

SERIES ESTABLISHED: Mesa County, Colorado, 1970.

REMARKS: This update moves the type location from Mesa County, Colorado, to Moffat County, Colorado. Diagnostic features include a mollic epipedon from 0 to 20 inches and a lithic contact at 31 inches. Last updated by the state 4/95.


National Cooperative Soil Survey
U.S.A.