LOCATION STORMITT UT+MTEstablished Series
TAXONOMIC CLASS: Loamy-skeletal, carbonatic, mesic Ustic Haplocalcids
TYPICAL PEDON: Stormitt loam-rangeland. (Colors are for air-dry soil unless otherwise noted.)
A1--0 to 3 inches; reddish brown (5YR 5/3) gravelly loam, reddish brown (5YR 4/4) moist; very fine granular structure; soft, very friable, slightly sticky and slightly plastic; few fine roots; few fine interstitial pores; 20 percent gravel; strongly calcareous; carbonates are disseminated; moderately alkaline (pH 8.2); clear smooth boundary. (1 to 7 inches thick)
Bw--3 to 12 inches; reddish brown (5YR 5/4) very cobbly clay loam, reddish brown (5YR 4/4) moist; moderate medium subangular blocky structure; hard, firm, sticky and plastic; few fine and medium roots; few fine tubular pores; 40 percent cobbles and gravel; strongly calcareous; carbonates are disseminated; moderately alkaline (pH 8.2); gradual smooth boundary. (8 to 12 inches thick)
Bk1--12 to 18 inches; light reddish brown (5YR 6/3) very cobbly clay loam, reddish brown (5YR 5/3) moist; weak medium subangular blocky structure; slightly hard, friable, sticky and plastic; few fine roots; few fine pores; 20 percent cobbles, 20 percent gravel; very strongly calcareous; carbonates are in masses; moderately alkaline (pH 8.3); gradual wavy boundary. (6 to 11 inches thick)
Bk2--18 to 60 inches; pinkish white (5YR 8/2) very cobbly loam, pinkish gray (5YR 6/2) moist; massive; slightly hard or hard, friable, slightly sticky and slightly plastic; few fine roots; few fine pores; 30 percent cobbles and 20 percent gravel; very strongly calcareous; carbonates are in masses; moderately alkaline (pH 8.4).
TYPE LOCATION: Garfield County, Utah; 2,280 feet east and 1,200 feet south of the northwest corner of sec. 8, T. 33 S., R. 12 E.
RANGE IN CHARACTERISTICS:
Rock fragments: 35 to 60 percent
Clay content: 18 to 35 percent
Calcium carbonate equivalent: averages 40 to 70 percent (control section)
Mean annual soil temperature: 49 to 53 degrees F.
Soil Moisture: Ustic aridic moisture regime.
A horizon
Hue: 2.5YR through 10YR
Value: 5 or 6 dry, 3 through 5 moist
Chroma: 2 through 4
Bw horizon
Hue: 2.5YR through 10YR
Value: 4 through 6 dry
Chroma: 2 through 5
Texture: gravelly loam, gravelly sandy clay loam, or very cobbly clay loam
Bk horizon
Hue: 2.5YR through 10YR
Value: 6 to 8 dry, 5 or 6 moist
Chroma: 4 through 6
Texture: very cobbly loam, very cobbly sandy clay loam, very cobbly clay loam or very gravelly silty clay loam.
COMPETING SERIES: These are the Ildecarb (NM), Ladron (NM), Moab (UT), Puice (NM), Socorro (NM), Storsun (WY), and Tusayan (AZ) series. The Ildcarb soils contain 5 to 15 percent gypsum in the fine earth fraction in the 10 to 40 inch section. The Ladron soils have a lithologic discontinuity within a depth of 40 inches. The Moab soils contain less than 18 percent clay in the 10 to 40 inch particle size control section. The Puice, Socorro, and Tusayan soils have bedrock between a depth of 20 and 40 inches. Storsun soils have hue of 10YR.
GEOGRAPHIC SETTING: Stormitt soils are on sloping stream terraces, benches, hillslopes, and fans at elevations of 4,000 to 6,800 feet. Slopes range from 2 to 30 percent. The alluvium is from a mixture of limestone, diorite, quartzite and sandstone and shale. The climate is warm and arid with mean annual temperature of 47 to 51 degrees F. Mean annual precipitation is 8 to 12 inches. Mean summer temperature is 59 to 63 degrees F. Freeze-free period is 90 to 150 days.
GEOGRAPHICALLY ASSOCIATED SOILS: These are the Begay, Mido and Rizozo soils. Begay and Mido soils lack rock fragments in the particle-size control section. Rizozo soils have sandstone at a depth of less than 20 inches.
DRAINAGE AND PERMEABILITY: Well-drained; slow to medium runoff; moderately permeable.
USE AND VEGETATION: These soils are used for rangeland. Present vegetation is needleandthread, galleta, fourwing saltbush, blackbrush and Mormon-tea.
DISTRIBUTION AND EXTENT: South-central Utah (LRR-D MLRAs 34B and 35) and south-central Montana (LRR-E MLRA 46 & LRR-G MLRA 58A). Use of this series in all these LRRs should be evaluated and consideration should be given to discontinuing use in one or more LRRs.. Stormitt soils are extensive.
MLRA SOIL SURVEY REGIONAL OFFICE (MO) RESPONSIBLE: Phoenix, Arizona
SERIES ESTABLISHED: Big Horn County (Big Horn Area), Montana, 1970.
REMARKS: Diagnostic horizons and features recognized in this pedon are:
Ochric epipedon - the zone from the surface of the soil to 3 inches (A horizon).
Cambic horizon - the zone from 3 to 12 inches. (Bw horizon)
Calcic horizon - the zone of carbonate accumulation from 12 to 60 inches (Bk1, Bk2 horizons).
Particle-size control section - the zone from 10 to 40 inches.
Classified according to Soil Taxonomy Second Edition, 1999.
Classification changed from Ustollic Calciorthids to Ustic Haplocalcids in 12/94.