LOCATION VANOCKER                SD+WY

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

VANOCKER SERIES

The Vanocker series consists of deep to very deep, well drained soils formed in residuum and colluvium from sedimentary rocks. Vanocker soils are on gently sloping to very steep ridges and hillslopes in mountains. They have moderately low and moderately high saturated hydraulic conductivity. Slopes range from 2 to 80 percent. The mean annual precipitation is about 585 mm and the mean annual temperature is about 6 degrees C.

TAXONOMIC CLASS: Loamy-skeletal, mixed, superactive, frigid Inceptic Hapludalfs

TYPICAL PEDON: Vanocker gravelly silt loam, on a west-facing, linear slope of 38 percent under ponderosa pine forest at an elevation of 1,432 meters. When described on June 1, 1976 the soil was dry throughout. (Colors are for moist soil unless otherwise noted).

0e--0 to 2.5 cm; forest litter and partially decomposed forest litter consisting of mixed coniferous and deciduous residue. (1 to 6 cm thick)

A--2.5 to 7.5 cm; black (10YR 2/1) and very dark grayish brown (10YR 3/2) gravelly silt loam, very dark grayish brown (10YR 3/2) and dark grayish brown (10YR 4/2) dry; weak very fine granular structure; soft, very friable, slightly sticky and slightly plastic; many fine, medium, and coarse roots; 30 percent by volume subangular limestone gravel; neutral; abrupt wavy boundary. (0 to 8 cm thick)

Bt--7.5 to 18 cm; brown (10YR 4/3) very gravelly silty clay loam, brown (10YR 5/3) dry; moderate fine subangular blocky structure; slightly hard, friable, moderately sticky and moderately plastic; many fine, medium and coarse roots; many faint continuous clay films on faces of peds; 40 percent by volume subangular limestone gravel; disseminated calcium carbonate throughout; very slight effervescence; slightly alkaline; clear wavy boundary. (7 to 25 cm thick)

Btk--18 to 40 cm; brown (10YR 4/3) very gravelly clay loam, brown (10YR 5/3) dry; moderate ffine and medium subangular blocky structure; slightly hard, friable, slightly sticky and slightly plastic; common fine, medium, and coarse roots; 55 percent by volume subangular limestone gravel; common medium and coarse accumulations of calcium carbonate throughout and on the bottom of rock fragments; slight effervescence; slightly alkaline; clear wavy boundary. (0 to 38 cm thick)

Bk1--40 to 104 cm; brown (10YR 5/3) very gravelly loam, light gray (10YR 7/2) dry; weak fine and medium subangular blocky structure; slightly hard, friable, slightly sticky and slightly plastic; few medium and coarse roots; 55 percent by volume subangular limestone gravel; few (3 percent) fine threads of calcium carbonate in soil matrix and medium and coarse calcium carbonate coatings on the bottom of rock fragments; strong effervescence; moderately alkaline; gradual wavy boundary. (10 to 76 cm thick)

Bk2--104 to 152 cm; brown (10YR 4/3) extremely gravelly silt loam, brown (10YR 5/3) dry; weak fine and medium subangular blocky structure; slightly hard, friable, slightly sticky and nonplastic; few medium and coarse roots; 65 percent by volume subangular limestone gravel; few (3 percent) fine threads of calcium carbonate in matrix and continuous calcium carbonate coatings on faces of peds; violent effervescence; moderately alkaline.

TYPE LOCATION: Meade County, South Dakota; about 4 miles south and 2 miles west of Sturgis; about 1,500 feet east and 100 feet south of the northwest corner of Sec. 5, T. 4 N., R. 5 E.; Deadman Mountain USGS quadrangle; 44 degrees 20 minutes 37 seconds north latitude, and 103 degrees 32 minutes 49 seconds west longitude; NAD 83.

RANGE IN CHARACTERISTICS:
Soil moisture: Typic-udic soil moisture regime.
Depth to secondary calcium carbonate: 10 to 38 cm

Particle-size control section (weighted average):
Clay content: 18 to 35 percent
Sand content: typically 5 to 15 percent fine and coarser sand; ranges to 35 percent in some pedons

A horizon:
Hue: 7.5YR or 10YR
Value: 3 to 6, 2 to 4 moist
Chroma: 2 or 3
Texture: L, SIL, FSL, VFSL (fine-earth fraction)
Clay content: 8 to 27 percent
Rock fragments: 5 to 35 percent total volume of non-flat subangular or subrounded gravel, or flat subangular or subrounded channers, and 0 to 5 percent cobble
Reaction: moderately acid to neutral

An E horizon is present in place of the A in a few pedons; it has properties similar to the A except that moist and dry colors are one value lighter.

Bt horizon:
Hue: 2.5YR, 5YR, 7.5YR, 10YR, or 2.5Y
Value: 5 to 7, 4 to 6 moist
Chroma: 2 to 4
Texture: CL, SICL, SCL (fine-earth fraction)
Clay content: 25 to 35 percent
Rock fragments: 30 to 45 percent total volume of non-flat subangular or subrounded gravel or flat, subangular or subrounded channers, and 0 to 15 percent cobble
Calcium carbonate equivalent: 0 to 10 percent
Reaction: moderately acid to slightly alkaline

Btk horizon:
Hue: 2.5YR, 5YR, 7.5YR, 10YR, or 2.5Y
Value: 5 to 7, 4 to 6 moist
Chroma: 2 to 6
Texture: L, SIL, CL, SICL, SCL (fine-earth fraction)
Clay content: 20 to 35 percent
Rock fragments: 30 to 45 percent total volume of non-flat subangular or subrounded gravel or flat ,subangular or subrounded channers, and 0 to 15 percent cobble
Calcium carbonate equivalent: 10 to 20 percent
Reaction: slightly alkaline

Bk horizon:
Hue: 2.5YR, 5YR, 7.5YR, 10YR, or 2.5Y
Value: 5 to 8, 4 to 7 moist
Chroma: 2 to 6
Texture: L, CL, SIL, SICL, SL, FSL, SCL (fine-earth fraction)
Clay content: 15 to 35 percent
Rock fragments: 20 to 55 percent total volume of non-flat subangular or subrounded gravel, or flat subangular or subrounded channers, 5 to 30 percent cobble, and/or 0 to 20 percent flagstones
Calcium carbonate equivalent: 15 to 40 percent
Reaction: slightly alkaline or moderately alkaline

Some pedons contain a C horizon

COMPETING SERIES:
Marquette - have fine-earth textures of fine sandy loam or coarser throughout; additionally they formed in glacial outwash

GEOGRAPHIC SETTING:
Parent material: colluvium and/or residuum derived primarily from limestone and/or calcareous sandstone
Landform: ridges, ridge shoulders, and hillslopes of mountains
Slopes: 2 to 80 percent
Elevation: 1,095 to 1,890 meters
Mean annual temperature: 4 to 7 degrees C)
Mean annual precipitation: 510 to 760 mm
Precipitation pattern: over one-half the mean annual precipitation falls as snow and rain during the period March through July
Frost-free season: 60 to 110 days

GEOGRAPHICALLY ASSOCIATED SOILS: These are the Citadel, Hopdraw, Rockerville(T), Sawdust, and Tollflat (T) soils.
Citadel and Tollflat (T) - are fine-textured; they generally occur below Vanocker soils on the landscape
Hopdraw - are sandy-skeletal and lack argillic horizons; they occur on similar landscape positions as Vanocker soils
Rockerville(T) - are shallow to a lithic contact; they generally occur above Vanocker soils on the landscape
Sawdust - lack argillic horizons; on similar landscape positions as Vanocker

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

USE AND VEGETATION: Used for timber production, recreation and wildlife habitat, and for grazing. Native vegetation is dominantly ponderosa pine with lesser amounts of aspen, birch, and bur oak. Understory species include Kentucky bluegrass, needlegrass, timber oatgrass, roughleaf ricegrass, and little bluestem. Shrubs include bearberry, oregon-grape, common juniper, buffaloberry, and snowberry.

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

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

SERIES ESTABLISHED: Meade County, South Dakota, Southern Part, 1974.

REMARKS: Diagnostic horizons and features recognized in this pedon are:
Ochric epipedon - 2.5 to 7.5 cm (A horizon)
Argillic horizon - 7.5 to 40 cm (Bt and Btk horizons)

The classification of the series was revised from Typic Eutroboralfs to Inceptic Hapludalfs due to changes in Soil Taxonomy (02/1999).

Taxonomic Version: Keys to Soil Taxonomy, Eleventh Ed., 2006

ADDITIONAL DATA:

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National Cooperative Soil Survey
U.S.A.