LOCATION HORSEMOUNTAIN      UT
Established Series
Rev. JMS/KDS/RLB
08/2006

HORSEMOUNTAIN SERIES


The Horsemountain series consists of shallow over lime cemented hardpan, well drained, moderately permeable soils formed in alluvium derived from sedimentary rocks. Horsemountain soils are on fan remnants. Slopes are 2 to 15 percent. The mean annual precipitation is about 10 inches and the mean annual temperature is about 47 degrees F.

TAXONOMIC CLASS: Loamy, mixed, superactive, mesic, shallow Ustalfic Petrocalcids

TYPICAL PEDON: Horsemountain fine sandy loam, 2 to 15 percent slopes -- rangeland. (Colors are for air-dry soil unless otherwise stated).

A--0 to 4 inches; light brown (7.5YR 6/4) fine sandy loam, brown (7.5YR 4/3) moist; weak fine granular structure; soft, very friable, slightly sticky and slightly plastic; common very fine, fine, medium and coarse roots; many very fine interstitial and tubular pores; 3 percent gravel, 1 percent cobbles; noneffervescent; slightly alkaline (pH 7.5); abrupt wavy boundary. (1 to 5 inches thick)

Bt--4 to 7 inches; light reddish brown (5YR 6/4) loam, reddish brown (5YR 4/4) moist; moderate medium and fine subangular blocky structure; slightly hard, friable, slightly sticky and slightly plastic; common very fine, fine, medium and coarse roots; common very fine, fine, medium tubular pores; common thin clay films on faces of peds; 8 percent gravel, 1 percent cobbles; very slightly effervescent, carbonates are disseminated; slightly alkaline (pH 7.8); clear wavy boundary. (4 to 10 inches thick)

Btk--7 to 14 inches; light reddish brown (5YR 6/4) gravelly fine sandy loam, reddish brown (5YR 5/4) moist; moderate medium and fine subangular blocky structure; slightly hard, friable, slightly sticky and slightly plastic; common very fine, fine, medium and coarse roots; common very fine, fine, medium tubular pores; few to common thin clay films on faces of peds; 15 percent gravel, 2 percent cobbles; strongly effervescent with carbonates in the interior of the peds as common fine veins; moderately alkaline (pH 8.0); clear wavy boundary. (4 to 11 inches thick)

Bkm--14 to 19 inches; indurated petrocalcic layer of strongly effervescent, calcium carbonate cemented, extremely gravelly soil materials with a 0.5 to 1 inch thick laminar cap; root penetration is inhibited except through a few vertical fractures; strongly to violently effervescent; moderately alkaline (pH 8.4). clear wavy boundary. (8 to 30 inches thick)

Bk1--19 to 32 inches; yellow (10YR 7/6) very gravelly fine sandy loam, yellowish brown (10YR 5/4) moist; weak fine subangular blocky structure; slightly hard, very friable, slightly sticky and slightly plastic; common very fine, few fine and medium roots; many very fine interstitial and common very fine and fine tubular pores; 50 percent gravels, 7 percent cobbles, 1 percent stones; violently effervescent, carbonates are disseminated and segregated as moderately thick coatings on rock fragments; moderately alkaline (pH 8.3); clear wavy boundary. (7 to 13 inches thick)

Bk2--32 to 61 inches; light reddish brown (2.5YR 7/4) extremely gravelly loamy fine sand, light reddish brown (2.5YR 6/4) moist; single grained; loose, loose, nonsticky and nonplastic; common very fine, few fine and medium roots; many very fine and few fine interstitial pores; 60 percent gravels, 10 percent cobbles, 1 percent stones; violently effervescent, carbonates are segregated as (1 to 3 mm) moderately thick coatings on rock fragments; moderately alkaline (pH 8.2); abrupt wavy boundary. (10 to 29 inches thick)

Bk3--61 to 69 inches; pink (7.5YR 7/4) gravelly fine sandy loam, brown (7.5YR 5/4) moist; single grain; slightly hard, very friable, slightly sticky and slightly plastic; common very fine, few fine and medium roots; many very fine interstitial and common very fine tubular pores; 30 percent gravels, 2 percent cobbles; strongly effervescent, carbonates are segregated as 1 mm thick coatings on rock fragments; moderately alkaline (pH 8.1)

TYPE LOCATION: Kane County, Utah; about 3 miles southeast of Cannonville; 400 feet east 500 feet south of the northwest corner of sec. 8, T. 38S., R. 2W., SLBM; Cannonville, Utah USGS quadrangle; 37 degrees, 31 minutes, 14 seconds north latitude and 112 degrees, 2 minutes, 15 seconds west longitude; NAD 27.

RANGE IN CHARACTERISTICS:

Soil moisture: Ustic aridic moisture regime

Mean annual soil temperature: 47 to 52 degrees F.

Depth to calcic horizon: 7 to 20 inches

Depth to petrocalcic horizon: 10 to 20 inches

Particle-size control section: 18 to 27 percent clay

Rock fragments: 15 to 35 percent subrounded rock fragments

A horizon:
Hue: 5YR, 7.5YR or 10YR
Value: 4 to 6 dry and moist
Chroma: 2 to 4 dry and moist
Clay content: 5 to 20 percent
Rock fragments: 0 to 15 percent sandstone and quartzite gravel
Reaction: neutral or slightly alkaline

Bt horizon:
Hue: 5YR or 7.5YR
Value: 5 or 6 dry, 4 or 5 moist
Chroma: 4 to 6 dry or moist
Clay content: 18 to 30 percent
Rock fragments: 0 to 15 percent sandstone and quartzite gravel
Reaction: neutral or slightly alkaline

Btk horizon:
Hue: 5YR or 7.5YR
Value: 5 or 6 dry, 4 or 5 moist
Chroma: 4 to 6 dry and moist
Texture: gravelly fine sandy loam or gravelly sandy clay loam
Clay content: 18 to 30 percent
Rock fragments: 15 to 30 percent sandstone and quartzite gravel
Reaction: slightly alkaline or moderately alkaline

Bkm horizon:
Value: 5 to 7 dry, 4 to 6 moist
Chroma: 3 or 4 dry and moist
Soil texture after mixing pan material is extremely gravelly loamy sand or fine sandy loam soil material in pockets
Rock fragments: 15 to 75 percent sandstone and quartzite gravel

Bk horizons:
Hue: 2.5YR to 10YR
Value: 7 or 8 dry, 5 to 7 moist
Chroma: 4 to 6 moist
Texture: extremely gravelly, gravelly fine sandy loam or loamy fine sand
Clay content: 4 to 18 percent
Rock fragments: 15 to 75 percent sandstone and quartzite gravel and
cobbles
Reaction: moderately alkaline or strongly alkaline

COMPETING SERIES: There are no competing series.

GEOGRAPHIC SETTING:
Parent material: alluvium derived from sedimentary rocks
Landform: fan remnants and terraces
Slopes: 2 to 15 percent
Elevation: 4,900 to 6,000 feet
Mean annual precipitation: 9 to 12 inches
Mean annual air temperature: 45 to 52 degrees F.
Frost-free period: 120 to 160 days.

GEOGRAPHICALLY ASSOCIATED SOILS: These are the Abracon, Clapper and Paradox soils. The Abracon soils are very deep and do not have argillic horizons. The Clapper soils are loamy-skeletal and very deep. The Paradox soils are very deep and do not have petrocalcic horizons.

DRAINAGE AND PERMEABILITY: Well drained; low runoff; moderately rapid permeability.

USE AND VEGETATION: These soils are used for rangeland. Potential vegetation consists of Utah Juniper, pinyon pine, Wyoming big sagebrush, bitterbrush, mountain mahogany, Indian ricegrass, galleta, bottlebrush squirreltail and needleandthread. These soils have been correlated to the Semidesert Shallow Loam range site.

DISTRIBUTION AND EXTENT: Southern Utah; MLRA 35. The series is of small extent.

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

SERIES ESTABLISHED: Kane County, Grand Staircase-Escalante National Monument soil survey area, 2004. The name comes from a geographic name in the soil survey area.

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

Particle-size control section: The zone from 4 to 14 inches. (Bt and Btk horizons)

Ochric epipedon: The zone from the soil surface to a depth of 5 inches. (A horizon)

Argillic horizon: The zone from 4 to 14 inches. (Bt and Btk horizons)

Calcic horizon: The zone from 19 to 69 inches. (Bk horizons)

Petrocalcic horizon: The zone from 14 to 19 inches. (Bkm horizon)

The CEC activity class was inferred from laboratory data in the Grand Staircase-Escalante National Monument soil survey area.

Classified according to Soil Taxonomy Second Edition, 1999.


National Cooperative Soil Survey
U.S.A.