LOCATION MILOK UT +AZ CO WYEstablished Series
TAXONOMIC CLASS: Coarse-loamy, mixed, superactive, mesic Ustic Haplocalcids
TYPICAL PEDON: Milok loamy fine sand--rangeland. (Colors are for air- dry soil unless otherwise stated.)
A--0 to 4 inches; yellowish red (5YR 5/6) loamy fine sand, yellowish red (5YR 4/6) moist; single grain; soft, very friable; few fine and very fine roots; slightly calcareous, carbonates are disseminated; moderately alkaline (pH 8.0); abrupt smooth boundary. (1 to 4 inches thick)
Bw--4 to 12 inches; reddish yellow (5YR 6/6) loamy fine sand, yellowish red (5YR 5/6) moist; weak medium subangular blocky structure; slightly hard, very friable; common very fine and fine roots; few fine pores; slightly calcareous, carbonates are disseminated; moderately alkaline (pH 8.2); clear smooth boundary. (7 to 16 inches thick)
Bk1--12 to 25 inches; light brown (7.5YR 6/4) fine sandy loam, strong brown (7.5YR 5/6) moist; massive; hard, very friable, slightly sticky and slightly plastic; common fine and few medium roots; few fine pores; strongly calcareous, carbonates are disseminated and concentrated in masses; moderately alkaline (pH 8.2); clear wavy boundary. (12 to 25 inches thick)
Bk2--25 to 47 inches; light brown (7.5YR 6/4) fine sandy loam, strong brown (7.5YR 5/6) moist; massive; slightly hard, very friable, slightly sticky and slightly plastic; strongly calcareous, carbonates are disseminated and concentrated in masses; moderately alkaline (pH 8.4); clear wavy boundary. (10 to 30 inches thick)
C--47 to 60 inches; reddish yellow (7.5YR 6/6) gravelly loamy sand, strong brown (7.5YR 5/6) moist; massive; loose; slightly calcareous, carbonates are disseminated; moderately alkaline (pH 8.4).
TYPE LOCATION: Wayne County, Utah; about 25 miles northwest of Hanksville; about 700 feet west and 1,500 feet south in the northeast corner of sec. 28, T., 27 S., R. 15 E.
RANGE IN CHARACTERISTICS:
Mean annual soil temperature ranges from 47 to 56 degrees F.
Soil moisture-dry 50 to 75 percent of the time cumulative, when the soil temperature is greater than 41 degrees F., and are not moist for 90 consecutive days when the soil temperature is greater than 47 degrees F. Ustic aridic moisture regime.
Depth to the calcic horizon ranges from - 6 to 20 inches.
Particle size control section -
Clay content: 5 to 18 percent
Rock Fragments: Less than 35 percent
A horizon
Hue: 5YR or 7.5YR
Value: 4 to 6 dry and 3 to 5 moist
Chroma: 3 to 6
Bw horizon
Hue: 5YR or 7.5YR
Value: 5 or 6 dry and 4 to 6 moist
Chroma: 3 to 8
Texture: loamy fine sand, sandy loam, fine sandy loam, or loam
Rock fragments: 0 to 20 percent
Reaction: slightly calcareous to moderately calcareous
Bk horizon
Hue: 5YR or 7.5YR
Value: 5 to 8 dry and 4 to 6 moist
Chroma: 2 to 8
Textures: fine sandy loam, loam or sandy loam
Rock fragments: 0 to 30 percent
Reaction: moderately alkaline or strongly alkaline
C horizon (when present)
Hue: 5YR or 7.5YR
Value: 5 to 7 dry, 3 to 5 moist
Chroma: 4 to 7
Texture: sandy loam fine sandy loam, silt loam, or gravelly loamy sand
Reaction: moderately alkaline or strongly alkaline
COMPETING SERIES: These are the Abracon (UT), Anasazi (UT), Chroder (CO), Chugcity (WY), Chupadera (NM), Cobbra (UT), Harvey (NM), Mivida (UT), Nala (NM)(T), Sazi (UT) and Yattle (CO)(T) series. Anasazi, Chugcity, Chupadera and Sazi soils are moderately deep. Chroder soils contain 15 to 30 percent calcium carbonate in the particle-size control section. Cobbra soils contain 18 to 35 percent clay and average 15 to 40 percent calcium carbonate in the particle-size control section. Mivida and Yattle soils have a calcic horizon at 20 inches or deeper. Nala soils are more moist in the moisture control section from July through September due to additional run-on moisture. Harvey soils are moist in the control section during the spring and early summer months and contain 18 to 35 percent clay in the particle-size control section. Chugcity, Chupadera, Harvey and Yattle soils are in the Western Great Plains (LRR-G) and are more moist in May and June.
GEOGRAPHIC SETTING: Milok soils are on structural benches, fan terraces, fan remnants, mesas and ridges. Elevations range from 4,300 to 6,600 feet. Slope ranges from 0 to 65 percent. These soils formed in alluvium, colluvium and eolian material derived from sandstone and limestone.. The soils are in a warm, semiarid climate with average annual precipitation ranging from 10 to 14 inches. The precipitation is distributed evenly throughout the year with a slight bulge in July, August, September and October. The mean annual air temperature is 45 to 55 degrees F. The frost-free period is 100 to 165 days.
GEOGRAPHICALLY ASSOCIATED SOILS: These are the Begay, Chipeta and Mido soils. Begay soils do not have a calcic horizon. Chipeta soils have a paralithic contact at less than 20 inches. Mido soils have a sandy particle-size control section.
DRAINAGE AND PERMEABILITY: Well drained; low runoff; moderately rapid permeability.
USE AND VEGETATION: The soils are used for livestock grazing, wildlife habitat and recreation. Potential vegetation is mainly blackbrush, Indian ricegrass, galleta and Mormon-tea.
DISTRIBUTION AND EXTENT: Utah, Arizona, Colorado and Wyoming; MLRAs 34A, 34B and 35. The series is extensive.
MLRA OFFICE RESPONSIBLE: Phoenix, Arizona
SERIES ESTABLISHED: Wayne County, Utah, Henry Mountains Area, 1985.
REMARKS: Diagnostic horizons and features recognized in this pedon are:
Ochric epipedon - the zone from the surface to 4 inches. (A horizon)
Cambic horizon - the zone from 4 to 12 inches. (Bw horizon)
Calcic horizon - the zone from 12 to 47 inches. (Bk1, Bk2 horizons)
Particle-size control section - the zone from 10 to 40 inches.
Classification changed from Ustollic Calciorthids to Ustic Haplocalcids in 9/94.
The following statement was removed from the Range in Characteristics in the March 1993 update. "The moist period occurs during the 4 months following the summer solstice." There is a late summer and early fall spike in precipitation levels for the ustic aridic soils in Utah. Based on the Newhall Simulations for Utah stations (1961 to 1990 normal) the soils are dry in the moisture control section during the 4 months following the summer solstice in spite of the higher precipitation levels in the late summer and early fall.
Classified according to Keys to Soil Taxonomy Ninth Edition, 2003.