LOCATION RAPSON MI

Established Series
Rev. LHL-NWS-JKC
01/2017

RAPSON SERIES

The Rapson series consists of very deep, somewhat poorly drained soils that formed in sandy over loamy glaciolacustrine deposits. Rapson soils are on lake plains, glacial deltas, glacial drainageways, and beach ridges. Slope ranges from 0 to 6 percent. Mean annual precipitation is about 817 mm, and the mean annual temperature is about 9 degrees C.

TAXONOMIC CLASS: Sandy over loamy, mixed, semiactive, nonacid, mesic Aquic Udorthents
TYPICAL PEDON: Rapson loamy sand, on a south-facing, convex, 1 percent slope in a hardwood forest at an elevation of 204 meters. (Colors are for moist soil unless otherwise noted.)

A --0 to 10 cm; black (10YR 2/1) loamy sand; weak fine granular structure; very friable; 2 percent gravel; slightly acid; abrupt wavy boundary. (5 to 25 cm thick)

E --10 to 23 cm; light brownish gray (10YR 6/2) sand; single grain; loose; 2 percent gravel; neutral; abrupt irregular boundary. (0 to 23 cm thick)

Bw --23 to 36 cm; brown (7.5YR 4/4) loamy sand; weak fine subangular blocky structure; very friable; common medium distinct yellowish red (5YR 4/6) masses of oxidized iron; 2 percent gravel; neutral; abrupt wavy boundary. (10 to 41 cm thick)

BC --36 to 64 cm; yellowish brown (10YR 5/4) sand; single grain; loose; common medium distinct yellowish brown (10YR 5/6) and common medium prominent strong brown (7.5YR 5/8) masses of oxidized iron; 5 percent gravel; slightly alkaline; abrupt wavy boundary. (0 to 64 cm thick)

2C --64 to 142 cm; light olive brown (2.5Y 5/4) stratified very fine sand, silt loam, and fine sand; massive; very friable; common medium distinct grayish brown (10YR 5/2) iron depletions; common medium distinct yellowish brown (10YR 5/6) masses of oxidized iron; strongly effervescent; moderately alkaline; clear wavy boundary. (0 to 102 cm thick)

2Cg --142 to 152 cm; gray (5Y 5/1) stratified very fine sand and silt loam with thin lenses of silty clay loam; massive; friable; many coarse prominent light olive brown (2.5Y 5/4) masses of oxidized iron; 2 percent gravel; strongly effervescent; moderately alkaline.

TYPE LOCATION: Huron County, Michigan; about 1 mile south and 1 mile west of Harbor Beach; 1,395 feet south and 70 feet east of the northwest corner of sec. 14, T. 16 N., R. 15 E; USGS Harbor Beach topographic quadrangle; latitude 43 degrees 49 minutes 43.85 seconds N. and longitude 82 degrees 40 minutes 58.48 seconds W., WGS84.

RANGE IN CHARACTERISTICS:
Depth to the base of soil development: typically about 76 cm, but ranges from 51 to 96 cm
Depth to carbonates: typically about 76 cm, but ranges from 51 to 96 cm

A or Ap horizon, where present:
Hue: 7.5YR or 10YR
Value: 2 to 4
Chroma: 1 to 3
Texture: loamy sand, sand, fine sand, or loamy fine sand
Rock fragments: 0 to 5 percent
Reaction: moderately acid to slightly alkaline

E horizon:
Value: 5 or 6
Chroma: 2 or 3
Texture: loamy sand, sand, fine sand, or loamy fine sand
Rock fragments: 0 to 5 percent
Reaction: moderately acid to slightly alkaline

Bw horizon:
Hue: 7.5YR or 10YR
Value: 2 to 5
Chroma: 2 to 6
Texture: loamy sand, sand, fine sand, or loamy fine sand
Rock fragments content: 0 to 5 percent
Reaction: moderately acid to slightly alkaline

BC horizon:
Value: 5 or 6
Chroma: 2 to 4
Texture: sand or fine sand
Rock fragments: 0 to 8 percent

Some pedons have a thin sandy C horizon, 2.5 to 8 cm thick.

2C or 2Cg horizon:
Hue: 10YR to 5Y
Value: 4 to 6
Chroma: 1 to 4
Texture: strata of any texture occur, but very fine sand, silt, silt loam, and loam predominate; strata are 3 mm to 2.5 cm thick
Rock fragments: 0 to 3 percent

COMPETING SERIES: This is the Avoca series. Avoca soils are derived from till in the lower part of the series control section and have more than 5 percent rock fragments in the 2C horizon.

GEOGRAPHIC SETTING: Rapson soils are on lake plains, glacial deltas, glacial drainageways and beach ridges. Slope ranges from range from 0 to 6 percent. The soils formed in sandy glaciolacustrine deposits over loamy glaciolacustrine deposits. Mean annual precipitation ranges from 758 to 960 mm. Mean annual temperature ranges from 7 to 11 degrees C.

GEOGRAPHICALLY ASSOCIATED SOILS: These are the Pipestone, Sanilac, Selfridge and Wixom soils, all of which are on similar topographic positions. Pipestone soils do not have loamy C horizons. Sanilac soils do not have a sandy solum. Selfridge soils have an argillic horizon, and have less very fine sand and silt in the C horizon. Wixom soils have less very fine sand and silt in the C horizon.

DRAINAGE AND SATURATED HYDRAULIC CONDUCTIVITY: Somewhat poorly drained. Potential for surface runoff is negligible to low. Saturated hydraulic conductivity is high in the solum and moderately high in the substratum.

USE AND VEGETATION: About half of the areas of Rapson soils are cultivated. Corn and wheat are the principal crops. Wooded areas are primarily quaking aspen, red maple and white birch. Native vegetation is a mixture of hardwoods and conifers.

DISTRIBUTION AND EXTENT: MLRA 99. The series is of small extent.

MLRA SOIL SURVEY REGIONAL OFFICE (MO) RESPONSIBLE: AMHERST, MASSACHUSETTS

SERIES ESTABLISHED: Bay County, Michigan, 1978.

REMARKS: Diagnostic horizons and features recognized in this pedon are:
Ochric epipedon: from the surface to a depth of 23 cm (A and E horizons).
Albic horizon: 10 to 23 cm (E horizon).
Lithologic discontinuity: at 64 cm (top of the 2C horizon).
Aquic conditions: 64 to 152 cm (2C and 2Cg horizons)

Some pedons have been described with a Bs horizon that contains fragments of cemented soil material similar in appearance to weakly cemented ortstein. These areas require further study to characterize the cementing agent and soil chemistry of the profile.

A dense substratum phase is recognized.

A phase with a surface layer of human transported materials has been correlated. This layer is less than 50 cm thick and of variable textures.

National Cooperative Soil Survey
U.S.A.