LOCATION COLLETT            UT
Established Series
Rev. VLM/MEO/AJE/JMW
12/2003

COLLETT SERIES


The Collett series consists of very deep, somewhat poorly drained soils that formed in lake sediments. The Collett soils are on lake terrace. Slope ranges from 0 to 3 percent. The mean annual precipitation is about 15 inches and the mean annual temperature is 48 degrees F.

TAXONOMIC CLASS: Fine, mixed, active, mesic Aquic Calcixerolls

TYPICAL PEDON: Collett silty clay loam, cultivated. (Colors are for dry soil unless otherwise noted.)

Ap--0 to 7 inches; gray (10YR 5/1) silty clay loam, black (10YR 2/1) moist; moderate medium granular structure; slightly hard, friable, sticky and plastic; few fine roots; few fine pores; moderately calcareous; slightly alkaline (pH 7.6); clear smooth boundary. (4 to 8 inches thick)

A--7 to 12 inches; gray (10YR 5/1) heavy silty clay loam, very dark gray (10YR 3/1) moist; very weak medium prismatic structure that parts to moderate fine subangular blocky structure; hard, firm, sticky and plastic; common fine roots; slightly calcareous; slightly alkaline (pH 7.8); clear smooth boundary. (5 to 8 inches thick)

Bw--12 to 17 inches; gray (10YR 6/1) heavy silty clay loam, dark grayish brown (10YR 4/2) moist; weak medium and coarse prismatic structure that parts to moderate fine angular blocky structure; very hard, firm, sticky and plastic; common fine roots; few fine pores; moderately calcareous; moderately alkaline (pH 7.9); clear smooth boundary. (4 to 8 inches thick)

Ck1--17 to 24 inches; pale yellow (2.5Y 8/2) silty clay loam, light brownish gray (10YR 6/2) moist; weak medium subangular blocky structure that parts to weak fine subangular blocky structure; hard, firm, sticky and plastic; few fine roots; few fine pores; strongly calcareous; moderately alkaline (pH 8.4); clear smooth boundary. (7 to 10 inches thick)

Ck2--24 to 34 inches; pale yellow (2.5Y 8/2) silty clay loam, pale brown (10YR 6/3) moist; few fine distinct yellowish brown (10YR 5/6) mottles; weak medium subangular blocky structure; slightly hard, friable, slightly sticky and plastic; few fine roots; few fine pores; very strongly calcareous; moderately alkaline (pH 8.4); abrupt smooth boundary. (0 to 10 inches thick)

C--34 to 48 inches; very pale brown (10YR 8/2) silty clay loam, pale brown (10YR 6/3) moist; common medium distinct yellowish brown (10YR 5/8) mottles; moderate fine platy structure; laminated lake sediments; hard, friable, slightly sticky and plastic; few fine roots; strongly calcareous; moderately alkaline (pH 8.1).

TYPE LOCATION: Cache County, Utah; 1 1/2 miles south of the Logan-Cache Airport; 1,000 feet south and 1,000 feet east of the northeast corner of the southwest quarter of section 21, T.12N., R.1E.; Smithfield USGS quad; Latitude 41 degrees 45 minutes 48 seconds N. and Longitude 111 degrees 50 minutes 21 seconds W.

RANGE IN CHARACTERISTICS: The mean annual soil temperature is 48 to 50 degrees F., and the mean summer soil temperature at 20 inches is 62 to 68 degrees F. Water table occurs between 20 and 36 inches where not drained. The soils are usually moist but are dry in parts of the 4 and 12 inch depth for more than 90 days, but are not dry in all parts of the 4 and 12 inch depth for 60 consecutive days in 7 out of 10 years.

The mollic epipedon is 10 to 17 inches thick. The combined thickness of the A and B horizons is 16 and 22 inches. Few to common medium distinct yellowish brown to strong brown mottles occur at depths of 24 to 36 inches.

The A horizon has value of 4 or 5 dry, 2 or 3 moist, and chroma of less than 2. It has 2 to 4.5 percent organic matter. It has moderate medium granular structure in the upper portion and very weak medium prismatic or moderate fine subangular blocky structure in the lower portion. It is mildly to moderately alkaline, and is slightly to moderately calcareous.

The Ck horizon has 22 to 60 percent calcium carbonate equivalent.

The C horizon has hue of 2.5Y or 10YR, value of 6 through 8, 5 or 6 moist, and chroma of 2 or 3. It is silt loam to silty clay.

COMPETING SERIES: These are the Fingal, Greenson, Ironton, and Nibley series. Fingal soils are not saturated within 40 inches or more than 90 days. Greenson soils have less than 35 percent clay in the control section. Ironton soils have calcic horizons within 16 inches, lack cambic horizons and have silty loam with less than 18 percent clay and more than 15 percent coarser than very fine sand in the control section. Nibley soils have argillic horizons.

GEOGRAPHIC SETTING: Collett soils occur on nearly level to gently sloping low and medium lake terraces at elevations of 4,250 to 4,700 feet. Gradients are 0 to 3 percent. Parent materials are mixed lake sediments. The climate is dry subhumid. The average annual precipitation is 13 to 18 inches. The mean annual temperature is 46 to 51 degrees F., and the mean summer temperature is 68 to 72 degrees F. The frost free season ranges from 120 to 145 days.

GEOGRAPHICALLY ASSOCIATED SOILS: These are the competing Greenson, Nibley soils and the Cardon, Logan, and Salt Lake soils. Cardon soils lack both cambic and calcic horizons. Logan and Salt Lake soils have calcic horizons within 16 inches, directly under the mollic epipedon.

DRAINAGE AND PERMEABILITY: Somewhat poorly drained; slow runoff; slow permeability.

USE AND VEGETATION: This soil is used mainly for irrigated cropland of alfalfa, small grains, sugar beets and pasture. The native vegetation is meadow foxtail, Kentucky bluegrass, salt grass, and some areas of sedges and wiregrass.

DISTRIBUTION AND EXTENT: ow lake terraces in Northern Utah. This series is inextensive.

MLRA SOIL SURVEY REGIONAL OFFICE (MO) RESPONSIBLE: Phoenix, Arizona

SERIES ESTABLISHED: Cache Area, Utah, 1969.


National Cooperative Soil Survey
U.S.A.