LOCATION HOMKO              UT
Established Series
Rev. RHF/CSW/JWB
07/2010

HOMKO SERIES


The Homko series consists of very deep, well drained, slowly permeable soils that formed in alluvium derived from sedimentary and metamorphic rocks. Homko soils are on strath and stream terraces. Slopes range from 0 to 4 percent. Mean annual precipitation is about 7 inches and the mean annual temperature is about 46 degrees F.

TAXONOMIC CLASS: Fine-loamy, mixed, superactive, mesic Typic Natrargids

TYPICAL PEDON: Homko loam, on a southeast facing, linear, 0.5 percent slope in shadscale and Castle Valley saltbush rangeland at an elevation of 5,040 feet. (Colors are for dry soil unless otherwise noted.)

E--0 to 2 inches; light yellowish brown (10YR 6/4) loam, brown (7.5YR 4/4) moist; moderate thin platy structure parting to moderate very fine and fine subangular blocky; slightly hard, very friable, nonsticky and nonplastic; few very fine, fine and medium roots; many very fine, fine, few medium vesicular pores; 5 percent gravel; EC=2 mmhos/cm; very slightly effervescent (3 percent calcium carbonate equivalent), carbonates are disseminated; moderately alkaline (pH 8.4); abrupt smooth boundary. (1 to 3 inches thick)

Btkn1--2 to 11 inches; pink (7.5YR 7/4) clay loam, brown (7.5YR 5/4) moist; strong medium and coarse prismatic structure parting to moderate very fine subangular blocky; very hard, firm, moderately sticky and moderately plastic; few very fine, fine and medium roots; many very fine, common fine, few medium tubular pores; 5 percent gravel; EC=6 mmhos/cm; many discontinuous distinct clay films on faces of peds; slightly effervescent (7 percent calcium carbonate equivalent), carbonates are disseminated and segregated as common irregular medium masses in interior of peds; very strongly alkaline (pH 9.2); clear wavy boundary.

Btkn2--11 to 19 inches; pink (7.5YR 7/4) clay loam, strong brown (7.5YR 5/6) moist; moderate coarse prismatic structure parting to moderate fine and medium subangular blocky; very hard, firm, moderately sticky and moderately plastic; few very fine and fine roots; common very fine and fine, few medium tubular pores; 5 percent gravel; EC=6 mmhos/cm; common discontinuous distinct clay films on faces of peds and clay bridges between sand grains; strongly effervescent (8 percent calcium carbonate equivalent), carbonates are disseminated and segregated as common irregular medium masses; very strongly alkaline (pH 9.4); clear wavy boundary. (combined thickness of Btkn horizons range from 13 to 26 inches)

Bkn--19 to 32 inches; pink (7.5YR 7/4) clay loam, strong brown (7.5YR 5/6) moist; moderate fine subangular blocky structure parting to moderate very fine and fine subangular blocky; very hard, firm, moderately sticky and moderately plastic; few very fine and fine roots; many very fine and medium, common fine tubular pores; 5 percent gravel; EC=12 mmhos/cm; strongly effervescent (27 percent calcium carbonate equivalent), carbonates are disseminated and segregated as few cylindrical fine masses; very strongly alkaline (pH 9.4); clear wavy boundary. (10 to 29 inches thick)

Bkny1--32 to 40 inches; pink (7.5YR 7/4) clay loam, strong brown (7.5YR 5/6) moist; weak fine and medium subangular blocky structure; very hard, firm, moderately sticky and moderately plastic; few very fine roots; many very fine, few fine tubular pores; 5 percent gravel; EC=11 mmhos/cm; few irregular fine masses of gypsum; strongly effervescent (22 percent calcium carbonate equivalent), carbonates are disseminated and segregated as few cylindrical fine masses; very strongly alkaline (pH 9.3); clear smooth boundary. (0 to 15 inches thick)

Bkny2--40 to 53 inches; pink (7.5YR 7/4) clay loam, strong brown (7.5YR 5/6) moist; massive; hard, firm, moderately sticky and moderately plastic; few fine roots; common very fine, few fine tubular pores; 10 percent gravel; EC=11 mmhos/cm; common irregular medium and coarse masses and crystals of gypsum; slightly effervescent (20 percent calcium carbonate equivalent), carbonates are disseminated and segregated as few cylindrical masses; strongly alkaline (pH 9.0); gradual wavy boundary.

Bny--53 to 60 inches; pink (7.5YR 7/4) clay loam, reddish yellow (7.5YR 6/6) moist; massive; hard, firm, moderately sticky and moderately plastic; few fine roots; common very fine, few fine tubular pores; 5 percent gravel; EC=14 mmhos/cm; few rounded medium and coarse crystals of gypsum; slightly effervescent (17 percent calcium carbonate equivalent), carbonates are disseminated; very strongly alkaline (pH 9.2).

TYPE LOCATION: Uintah County, Utah; along Rasmussen Hollow, about 2 miles southwest of the Ashley Oil Field; located about 1,900 feet east and 300 feet south of the northwest corner of sec. 33, T. 5 S., R. 22 E., SLBM; Rasmussen Hollow USGS quad; lat. 40 degrees 20 minutes 47 seconds N. and long. 109 degrees 27 minutes 08 seconds W., NAD 27

RANGE IN CHARACTERISTICS:

Soil moisture: Soil moisture control section is usually dry, but intermittently moist during late summer and early fall. Aridic moisture regime.
Mean annual soil temperature: 47 to 52 degrees F.
Depth to natric horizon: 1 to 3 inches
Depth to calcic horizon: 10 to 27 inches
Depth to gypsum accumulations: 24 to 58 inches

Particle-size control section: 27 to 35 percent clay; 0 to 15 percent gravel of sedimentary and metamorphic origin

E horizon:
Hue: 7.5YR or 10YR
Value: 5 to 7 dry, 4 to 6 moist
Chroma: 2 to 4 dry or moist
Calcium carbonate equivalent: 1 to 10 percent
EC (mmhos/cm): 2 to 4
SAR: 5 to 13
Reaction: moderately alkaline to very strongly alkaline

Btkn or Btn horizon:
Hue: 7.5YR or 10YR
Value: 5 to 8 dry, 4 to 6 moist
Chroma: 2 to 5 dry or moist
Calcium carbonate equivalent: 1 to 15 percent
EC (mmhos/cm): 4 to 16
SAR: 13 to 100
Reaction: strongly alkaline or very strongly alkaline

Bkn horizon:
Hue: 7.5YR or 10YR
Value: 6 to 8 dry, 4 to 7 moist
Chroma: 2 to 5 dry or moist
Rock fragments: 0 to 15 percent gravel or channers
Calcium carbonate equivalent: 15 to 40 percent
EC (mmhos/cm): 4 to 16
SAR: 13 to 30
Gypsum: 0 to 1 percent
Reaction: strongly alkaline or very strongly alkaline

Bkny and Bny horizons:
Hue: 7.5YR or 10YR
Value: 6 to 8 dry, 4 to 7 moist
Chroma: 2 to 5 dry or moist
Rock fragments: 0 to 15 percent gravel or channers
Calcium carbonate equivalent: 15 to 40 percent
EC (mmhos/cm): 4 to 16
SAR: 13 to 30
Gypsum: 1 to 10 percent
Reaction: strongly alkaline or very strongly alkaline

COMPETING SERIES: Current competitors are the Azabache (NM), Fajada (NM), Hadden (T)(UT), Highrock (CA), Leebench (UT), Leeko (UT), Muff (WY), Pizene (NV), Recapture (UT), Rusty (NV), Swasey (UT), Terlco (NV), Thermosprings (T)(UT) and Uffens (UT) series.

Azabache, Highrock, Pizene, Terlco and Uffens: do not have a calcic horizon.

Fajada, Hadden, and Muff: 20 to 40 inches to a paralithic contact.

Highrock, Rusty, Terlco and Thermosprings: have soil moisture control sections that are affected by xeric precipitation patterns. Rusty also has 20 to 27 percent clay in the particle-size control section. Terlco also has mean annual soil temperature of 53.5 to 59 degrees F. Thermosprings also does not have gypsum accumulations.

Leebench: do no have visible accumulations of gypsum and have 15 to 80 percent rock fragments below the natric horizon.

Leeko: has more than 35 percent rock fragments below 40 inches.

Recapture : hue is 2.5YR or 5YR in the B and C horizons and mean annual soil temperatures greater than 52 degrees F.

Swasey: 20 to 40 inches to a lithic contact with basalt.

GEOGRAPHIC SETTING:
Parent material: alluvium derived from sedimentary and metamorphic rocks
Landform: strath and stream terraces
Slopes: 0 to 4 percent
Elevation: 4,800 to 6,500 feet
Mean annual air temperature: 45 to 50 degrees F.
Mean annual precipitation: 5 to 9 inches
Precipitation pattern: Wettest months are July to October and driest months are December and June.
Frost-free period: 110 to 160 days

GEOGRAPHICALLY ASSOCIATED SOILS: These are the Greybull, Hanksville, Utaline and the competing Uffens series.

Greybull and Hanksville soils occur on hillslopes and are moderately deep to weathered shale bedrock.

Uffens soils occur on stream terraces and do not have a calcic horizon.

Utaline soils occur on fan remnants and are loamy-skeletal.

DRAINAGE AND PERMEABILITY: Well drained, low and medium runoff, slow permeability.

USE AND VEGETATION: The major uses are rangeland, wildlife habitat, and recreation. The potential native plant community is Castle Valley saltbush, shadscale, Indian ricegrass, bud sagebrush, galleta, and bottlebrush squirreltail. This soil has been correlated to the Desert Alkali Bench (Castle Valley Saltbush) - 034XY101UT range site at the type location in Utah.

DISTRIBUTION AND EXTENT: Northeastern and central Utah. LRR D, MLRA 34B. This series is of small extent.

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

SERIES ESTABLISHED: Uintah County, Uintah Area Soil Survey, Utah. 1998. The name is coined.

REMARKS: Diagnostic horizons and features recognized in this pedon are:

Particle-size control section: The zone from 2 to 19 inches. (Btnk1 and Btnk2 horizons)
Ochric epipedon: The zone from 0 to 2 inches. (E horizon)
Natric horizon: The zone from 2 to 19 inches. (Btnk1 and Btnk2 horizons)
Calcic horizon: The zone from 19 to 53 inches or more. (Bkn, Bkny1 and Bkny2 horizons)
Gypsum: The presence of gypsum accumulations in the zone from 32 to 60 inches. (Bkny1, Bkny2, and Bny horizons)

Taxonomic version: Eleventh Edition, 2010.

The CEC activity class was inferred from laboratory data from similar soils in the Uintah Area Soil Survey.


National Cooperative Soil Survey
U.S.A.