LOCATION MOBERG             WI
Established Series
Rev. WDF-GWH
04/1999

MOBERG SERIES


The Moberg series consists of deep, somewhat excessively drained soils formed in a thin silty or loamy mantle and in the underlying very gravelly or extremely gravelly residuum (grus) weathered from granite. These soils have moderately rapid permeability in the silty or loamy mantle and rapid or very rapid in the residuum. Slopes range from 2 to 15 percent. Mean annual precipitation is 32 inches, and mean annual temperature is about 43 degrees F.

TAXONOMIC CLASS: Sandy-skeletal, mixed, frigid Typic Dystrudepts

TYPICAL PEDON: Moberg gravelly silt loam - on a 10 percent east-facing convex slope in a wooded pasture at an elevation of about 1250 feet. (Colors are for moist soil unless otherwise stated.)

A--0 to 4 inches; very dark grayish brown (10YR 3/2) gravelly silt loam, grayish brown (10YR 5/2) dry; moderate very fine granular structure; friable; many fine roots; about 15 percent angular granitic pebbles by volume; very strongly acid; abrupt wavy boundary. (2 to 5 inches thick)

Bw--4 to 12 inches; dark brown (7.5YR 4/4) gravelly silt loam; moderate very fine subangular blocky structure; friable; common fine roots; about 30 percent angular granitic pebbles by volume; strongly acid; clear wavy boundary. (7 to 12 inches thick)

2BC--12 to 20 inches; strong brown (7.5YR 4/6) very gravelly sandy loam; weak very fine subangular blocky structure; very friable; few fine roots; about 60 percent angular granitic pebbles by volume; very strongly acid; clear wavy boundary. (6 to 13 inches thick)

2C--20 TO 60 INCHES; strong brown (7.5YR 5/6) extremely gravelly loamy coarse sand; single grain; about 80 percent coarse fragments by volume; very strongly acid.

TYPE LOCATION: Marathon County, Wisconsin; about 5 miles south of Marathon; 1500 feet east and 50 feet north of the southwest corner of sec. 32, T. 28 N., R. 6 E.

RANGE IN CHARACTERISTICS: Solum thickness ranges from 15 to 30 inches. Thickness of the silt loam mantle over the residuum weathered from granite rock (grus) is 15 inches or less. The A and Bw horizons are very strongly acid to slightly acid. The 2BC and 2C horizons are very strongly acid to medium acid. Volume of pebbles ranges from 10 to 35 percent in the A and Bw horizons and 35 to 90 percent in the 2BC and 2C horizons. See the REMARKS section for a discussion on the character of the coarse fragments in the residuum (grus). Volume of cobbles ranges from 0 to 2 percent in the A and Bw horizons and 0 to 8 percent in the 2BC and 2C horizons. The particle-size control section ranges from 35 to 55 percent coarse fragments by volume and the texture of the fine earth is sand or loamy sand.

The A or Ap horizon has 10YR hue, value of 2 through 4, and chroma of 1 through 3. It is silt loam, loam, or the gravelly analogues. Some pedons have an E horizon with 10YR or 7.5YR hue, value of 5 or 6, and chroma of 2 or 3. It has textures similar to the A or Ap horizon.

The Bw horizon has 10YR or 7.5YR hue, value and chroma is 4 or 5. It is silt loam, loam, or the gravelly analogues.

The 2BC horizon has 7.5YR or 5YR hue, value and chroma is 4 through 6. It is very gravelly or extremely gravelly loamy sand, loamy coarse sand, sandy loam, or coarse sandy loam.

The 2C horizon has 7.5YR or 5YR hue, value and chroma is 4 through 6. It consists of an accumulation of waste consisting of angular, coarse-grained fragments resulting from the granular disintegration of crystalline rocks (esp. granite). The pebble and cobble size fragments crush to sand size material without much difficulty.

COMPETING SERIES: This is the Elderon series in the same family. Other series in closely related families are Marathon and Mesaba. Elderon soils have 15 to 50 percent cobbles and stones in the B and C horizons and have coarse fragments of mixed lithology. Marathon soils are coarse-loamy and have tonguing of E material into the argillic horizon. Mesaba soils have a lithic contact of granitic rock at a depth of 20 to 40 inches.

GEOGRAPHIC SETTING: These soils are on uplands underlain by bedrock. Slope gradients range from 2 to 15 percent. They formed in thin silty or loamy deposits and the underlying very gravelly or extremely gravelly (grus) weathered from granite. Mean annual precipitation ranges from 28 to 36 inches, and mean annual temperature ranges from 42 to 46 degrees F.

GEOGRAPHICALLY ASSOCIATED SOILS: These are Marathon, Mosinee, and Mylrea soils. The well drained Marathon and somewhat poorly drained Mylrea soils are on nearby landscape positions where the silty mantle (loess) is thicker over the till or residuum weathered from granite, or both. Mosinee soils are on similar landscape positions as Moberg soils.

DRAINAGE AND PERMEABILITY: Somewhat excessively drained. Runoff is slow to medium. Permeability is moderately rapid in the silty or loamy mantle and rapid or very rapid in the underlying very gravelly or extremely gravelly residuum.

USE AND VEGETATION: Most areas of this soil are in pasture or woodland. Some areas are in cropland with corn, small grain, and hay as the main crops. In some places, ginseng, a high-value specialty crop, is also grown. Native vegetation was mixed deciduous and coniferous forests.

DISTRIBUTION AND EXTENT: Marathon County, Wisconsin. This series is inextensive.

MLRA SOIL SURVEY REGIONAL OFFICE (MO) RESPONSIBLE: St. Paul, Minnesota

SERIES ESTABLISHED: Marathon County, Wisconsin, 1986.

REMARKS: These soils appear to straddle the loamy-skeletal and sandy-skeletal particle-size classes, but more pedons can be placed in the sandy-skeletal and this will be the concept.

The highly weathered granite (grus) has undergone extensive chemical and mechanical weathering and the granite pebble size and cobble size fragments crush to sand and silt size fragments. The pebble size fragments, in place, behave as gravel in-so-far as the bulk density, permeability, and available water are concerned. As a construction material, the pebble size fragments crush to sand and silt size material. The logical UNIFIED classification is SM or SP. The pebble size fragments are not suitable for aggregate so it is not a probable source of sand or gravel.

Diagnostic horizon and features recognized in this pedon are: ochric epipedon - the zone from the surface of the soil to a depth of 4 inches (A horizon); cambic horizon - the zone from 4 to 20 inches (Bw, 2BC horizons); do not have carbonates in the cambic horizon or in the C horizon within the soil; do not have mottles that have chroma of 2 or less within 24 inches of the soil surface; do not have a lithic contact within a depth of 20 inches.


National Cooperative Soil Survey
U.S.A.