LOCATION STOVHO                  SD+WY

Established Series
Rev. ACM-KEC-JWW
06/2011

STOVHO SERIES

The Stovho series consists of deep and very deep, well drained soils formed in residuum weathered from limestone and calcareous, fine-grained sandstone on mountains. They have moderately low and moderately high saturated hydraulic conductivity. Slopes range from 0 to 50 percent. The mean annual precipitation is about 790 mm and the mean annual air temperature is about 3 degrees C.

TAXONOMIC CLASS: Fine, smectitic Eutric Glossocryalfs

TYPICAL PEDON: Stovho silt loam, on nearly level slope of 1 percent, under ponderosa pine forest at an elevation of 2,085 meters. When described on August 30, 1980, the soil was moist throughout. (Colors are for moist soil unless otherwise stated.)

Oi--0 to 2 cm; slightly decomposed forest litter. (0 to 5 cm thick)

A--2 to 7.5 cm; black (10YR 2/1) silt loam, dark gray (10YR 4/1) dry; weak medium platy structure; soft, very friable, nonsticky and nonplastic; many very fine and fine, common medium roots; moderately acid; clear smooth boundary. (0 to 12 cm thick)

E--7.5 to 18 cm; grayish brown (10YR 5/2) silt loam, light gray (10YR 7/2) dry; weak fine and medium platy structure; soft, very friable, nonsticky and nonplastic; many very fine and fine, common medium roots moderately acid; clear wavy boundary. (5 to 22 cm thick)

Bt/E--18 to 23 cm; brown (10YR 4/3) silty clay loam, pale brown (10YR 6/3) dry (Bt part); grayish brown (10YR 5/2) silt loam, light gray (10YR 7/2) dry (E part); weak medium prismatic structure parting to moderate fine and medium angular blocky; slightly hard, friable, slightly sticky and slightly plastic; common medium, fine, and very fine roots; slightly acid; abrupt wavy boundary. (5 to 34 cm thick)

Bt--23 to 46 cm; dark yellowish brown (10YR 4/4) silty clay, yellowish brown (10YR 5/4) dry; weak medium prismatic structure parting to strong medium blocky; hard, firm, moderately sticky and plastic; common very fine, fine and medium; slightly acid; clear wavy boundary. (20 to 63 cm thick)

Bk--46 to 79 cm; yellowish brown (10YR 5/4) silty clay loam, light yellowish brown (10YR 6/4) dry; weak coarse prismatic structure; hard, firm, moderately sticky and moderately plastic; few very fine and fine roots; 10 percent limestone channers; few fine filaments and threads of calcium carbonate; strongly effervescent; slightly alkaline; gradual wavy boundary. (10 to 51 cm thick)

C--79 to 152 cm; yellowish brown (10YR 5/6) channery silty clay loam, yellow (10YR 7/6) dry; massive; slightly hard, friable, moderately sticky and moderately plastic; few very fine and fine roots; 25 percent limestone channers; calcium carbonate mostly disseminated; violently effervescent; moderately alkaline.

TYPE LOCATION: Pennington County, South Dakota; about 4 miles south and 12 miles west of Hill City; 1500 feet east and 2,000 feet north of the southwest corner of Sec. 18, T. 2 S., R. 3 E.; Signal Hill Quadrangle; 43 degrees 52 minutes 26.9 seconds north latitude, 103 degrees 48 minutes 35.8 seconds west longitude; NAD 83.

RANGE IN CHARACTERISTICS:
Soil moisture: Typic-udic soil moisture regime.
Depth to secondary calcium carbonate is within 100 cm

Particle-size control section (weighted average):
Sand content: less than 10 percent fine and coarser sand

A horizon:
Hue: 10YR
Value: 2 or 3, 4 or 5 dry
Chroma: 1 or 2
Texture: L or SIL
Clay content: 10 to 25 percent
Reaction: moderately acid or slightly acid

E horizon:
Hue: 7.5YR or 10YR
Value: 4 or 5, 5 to 7 dry
Chroma: 2 or 3
Texture: L, SIL, or VFSL
Clay content: 10 to 20 percent
Reaction: moderately acid or slightly acid

The Bt/E horizon has the combined properties of the Bt and E horizons.

Bt horizon:
Hue: 7.5YR or 10YR
Value: 4 or 5, 5 to 7 dry
Chroma: 2 to 4
Texture: SICL, SIC, CL, or C (fine-earth fraction)
Rock fragments: 0 to 25 percent limestone and/or calcareous sandstone gravel
Reaction: moderately acid to neutral

A Btk horizon is present in some pedons.

Bk horizon:
Hue: 7.5YR or 10YR
Value: 4 to 6, 4 to 7 dry
Chroma: 2 to 4
Texture: SICL or CL (fine-earth fraction)
Rock fragments: 0 to 25 percent angular and subangular limestone, calcareous sandstone channers and/or cobbles
Reaction: neutral to moderately alkaline

C horizon:
Hue: 7.5YR, 10YR, or 2.5Y
Value: 5 to 7, 6 to 8 dry
Chroma: 2 to 6
Texture: SIL, SICL, or CL (fine-earth fraction)
Clay content: 20 to 35 percent
Rock fragments: 5 to 50 percent angular and subangular limeston, calcareous sandstone gravel or channers, cobbles, and stones
Calcium carbonate equivalent: 10 to 30 percent
Reaction: slightly alkaline or moderately alkaline

COMPETING SERIES: These are the Cowdrey, Gateway, and Muggins series.
These soils are noncalcareaous. Additionally the Cowdrey and Muggins soils contain greater than 15 percent fine and coarser sand and the Gateway soil have a paralithic contact at less than 100 cm.

GEOGRAPHIC SETTING:
Parent material: residuum, local alluvium, or colluvium typically derived from limestone or commonly from calcareous, fine-grained sandstone
Landform: ridges, ridge shoulders, and hillslopes of mountains
Slopes: 0 to 50 percent
Elevation: 1,890 to 2,134 meters
Mean annual temperature: 3 to 6 degrees C
Mean annual precipitation: 711 to 889 mm
Precipitation pattern: over one-half the mean annual precipitation falls as snow and rain during the period March through July
Frost-free season: less than 90 days

GEOGRAPHICALLY ASSOCIATED SOILS:
Gillum(T)and Jenksdraw - have mollic epipedons, additionally Jenksdraw soils are moderately deep to a lithic contact; these soils occur on similar, non-forested landscape positions as Stovho soils
Redbird - have a mollic epipedon and are loamy-skeletal; they occur in valleys below Stovho soils
Riflepit(T) - do not have a glossic horizon and have hue redder than 7.5YR; they occur on similar landscape positions as Stovho soils
Trebor - have a lithic contact within 100 cm and have carbonatic mineralogy; they occur on similar or higher landscape positions than Stovho soils

DRAINAGE AND SATURATED HYDRAULIC CONDUCTIVITY: Well drained; low to very high runoff, depending on slope; moderately low and moderately high saturated hydraulic conductivity.

USE AND VEGETATION: Stovho soils are used primarily for timber production, livestock grazing, wildlife habitat, and recreation. The dominant overstory is ponderosa pine and Black Hills spruce, with locally significant colonies of aspen and birch. The dominant understory is sedges, bearded wheatgrass, oatgrass, bromegrass, common juniper, Oregon grape, arrowleaf balsamroot, bearberry, and iris.

DISTRIBUTION AND EXTENT: High Limestone Plateau physiographic area of the Black Hills in western South Dakota and eastern Wyoming; LRR G, MLRA 62. The series is of moderate extent.

MLRA SOIL SURVEY REGIONAL OFFICE (MO) RESPONSIBLE: Denver, Colorado

SERIES ESTABLISHED: Lawrence County, South Dakota, 1977.

REMARKS: Diagnostic horizons and features recognized in this pedon are:
Ochric epipedon - 2 to 18 cm (A and E horizons)
Albic horizon - 7.5 to 18 cm (E horizon)
Glossic horizon - 18 to 23 cm (Bt/E horizon)
Argillic horizon - 18 to 46 cm (Bt/E and Bt horizons)

The classification of the series is revised from Inceptic Haplocryalfs to Eutric Glossocryalfs because the E horizon meets the criteria for an albic horizon and the Bt/E meets the criteria for a glossic horizon.

Keys to Soil Taxonomy, Tenth Ed., 2006

ADDITIONAL DATA:

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National Cooperative Soil Survey
U.S.A.