LOCATION BOETTCHER CO+MT WYEstablished Series
TAXONOMIC CLASS: Fine, smectitic, frigid Ustic Haplargids
TYPICAL PEDON: Boettcher clay loam - grassland. (Colors are for dry soil unless otherwise noted.)
A--0 to 4 inches; light brownish gray (10YR 6/2) clay loam, dark grayish brown (10YR 4/2) moist; strong, very fine granular structure; 1/2 inch vesicular crust on the surface; soft, very friable, slightly sticky, slightly plastic; 5 percent gravel; slightly alkaline (pH 7.6); gradual smooth boundary. (3 to 6 inches thick)
Bt--4 to 15 inches; brown (10YR 5/3) clay, brown (10YR 4/3) moist; moderate coarse prismatic structure parting to coarse and medium angular blocks; slightly hard, very friable, sticky, plastic; peds are extremely hard; thin continuous clay coatings on faces of peds;clay coatings and fillings in root channels; 5 percent gravel; slightly alkaline (pH 7.6); diffuse wavy boundary. (8 to 23 inches thick)
Bk1--15 to 22 inches; brown (10YR 5/3) clay, brown (10YR 4/3) moist; weak coarse prismatic structure parting to moderate coarse angular blocks; slightly hard, firm, very sticky, very plastic; peds are extremely hard; thin clay film patches on faces of peds; few clay fillings and coatings in root channels; some visible secondary calcium carbonate as concretions; strongly effervescent; moderately alkaline (pH 8.4); gradual wavy boundary. (4 to 8 inches thick)
Bk2--22 to 29 inches; pale brown (10YR 6/3) clay, brown (10YR 5/3) moist; massive; extremely hard, very firm, very sticky, very plastic; visible secondary calcium carbonate as concretions and in thin seams and streaks; violently effervescent; moderately alkaline (pH 8.4); gradual wavy boundary.
Cr--29 inches; calcareous shale.
TYPE LOCATION: Jackson County, Colorado; 1,400 feet east and 100 feet south of the NW corner, Sec. 20, T. 8 N, R. 79 W.
RANGE IN CHARACTERISTICS: Mean annual soil temperature is about 45 degrees F. and mean summer soil temperature is 59 degrees F. Depth to uniform calcareous material ranges from 6 to 40 inches. Depth to the paralithic contact ranges from 20 to 40 inches. Depth to the base of the argillic horizon ranges from 12 to 40 inches. Depth to continuous subhorizons of visible secondary calcium carbonate and/or sulfate ranges from 8 to 40 inches. Rock fragments range from 0 to 35 percent by volume in the solum and C horizon and are mainly 1/2 to 10 inches in diameter.
The A horizon has hue of 5Y through 7.5YR, value of 4 through 7, 3 through 6 moist, and chroma of 1 through 4. It is neutral or slightly alkaline.
The Bt horizon has hue of 5Y through 7.5YR, value of 4 through 7 dry, 3 through 6 moist, and chroma of 1 through 6. It ranges from clay loam to clay averaging 35 to 50 percent clay, 15 to 40 percent silt, and 15 to 45 percent sand with more than 15 percent fine or coarser sand. This horizon ranges from neutral to moderately alkaline.
The Bk horizon has hue of 5Y through 7.5YR, 6 or 7 dry, 4 through 6 moist and chroma of 3 or 4. It is clay loam or clay averaging 35 to 50 percent clay except that clay exceeds 50 percent in some pedons if total extensibility does not exceed 2.4 inches. This horizon is usually moderately or strongly alkaline but is very strongly alkaline in some subhorizons of the Bk horizon. Calcium carbonate equivalent ranges from about 4 to 14 percent.
COMPETING SERIES: These are the Kather (CO), Mulstay (CO), and Pinelli (WY) series. Kather soils lack carbonates throughout. Mulstay and Pinelli soils lack a paralithic contact above 40 inches.
GEOGRAPHIC SETTING: Boettcher soils are on upland hills and ridges. Slopes typically range from 0 to 30 percent. Elevation ranges from 8,000 to 9,000 feet. The soils formed in calcareous, fine textured sediments weathered from shale. At the type location the average annual precipitation is about 9 to 12 inches with peak periods of precipitation during the spring and early summer. The mean annual temperature is 36 to 38 degrees F and the mean summer temperature is 58 degrees F. Frost-free period is 35 to 50 days. In Montana, the Boettcher soils are at elevations of 2,500 to 4,500 feet with a frost-free season of 110 to 130 days and mean annual precipitation of 10 to 14 inches. In Utah these soils are at 6,400 to 6,900 foot elevation and range up to 44 degrees air temperature. Mean annual precipitation ranges to 14 inches and the frost-free period is 60 to 90 days.
GEOGRAPHICALLY ASSOCIATED SOILS: These are the Barishman and Bundyman soils. Barishman soils lack a paralithic contact above a depth of 40 inches and have continuous E horizons. Bundyman soils lack an argillic horizon.
DRAINAGE AND PERMEABILITY: Well-drained; medium runoff; slow permeability.
USE AND VEGETATION: These soils are used mainly as native pastureland. They are tilled to irrigated crops or hay crops in some locations. Principal native vegetation is junegrass, thickspike wheatgrass, big sage, and Matt saltbush.
DISTRIBUTION AND EXTENT: High mountain valleys of north-central Colorado and southeastern plains of Montana, and eastern parts of Utah. The series is of moderate extent.
MLRA SOIL SURVEY REGIONAL OFFICE (MO) RESPONSIBLE: Bozeman, Montana
SERIES ESTABLISHED: Jackson County, Colorado, 1973.
REMARKS: Diagnostic features include an argillic horizon at 4 to 15 inches, and organic carbon meets the requirement for Borollic. Last updated by the state 5/89.
The original concept of this series when correlated and established in 1973 was a cryic temperature regime and an aridic moisture regime.