LOCATION RIETBROCK          WI
Established Series
Rev. HFG-JJJ
12/2006

RIETBROCK SERIES


The Rietbrock series consists of somewhat poorly drained soils that are deep to a lithic contact with igneous or metamorphic bedrock. These soils formed in a thin mantle of loess or other silty deposits and in the underlying loamy till and residuum weathered from igneous and metamorphic bedrock on glaciated uplands. Permeability is moderate or moderately slow. Slopes range from 1 to 12 percent. Mean annual precipitation is about 32 inches. Mean annual air temperature is about 43 degrees F.

TAXONOMIC CLASS: Fine-loamy, mixed, superactive, frigid Aquic Glossudalfs

TYPICAL PEDON: Rietbrock silt loam - on a 5 percent slope in a cultivated field at an elevation of about 1390 feet. (Colors are for moist soil unless otherwise stated.)

Ap--0 to 8 inches; very dark grayish brown (10YR 3/2) silt loam, light brownish gray (10YR 6/2) dry; moderate very fine subangular blocky structure; friable; common fine roots; about 3 percent gravel; neutral; abrupt smooth boundary. (6 to 9 inches thick)

E--8 to 11 inches; brown (10YR 5/3) silt loam, very pale brown (10YR 7/3) dry; weak thin platy structure parting to moderate very fine subangular blocky; friable; few fine roots; few fine prominent strong brown (7.5YR 5/6) masses of iron accumulation in the matrix; about 3 percent gravel; neutral; clear wavy boundary. (0 to 8 inches thick)

E/B--11 to 15 inches; 60 percent brown (10YR 5/3) silt loam (E), very pale brown (10YR 7/3) dry; weak medium platy structure; friable; extends as tongues into and surrounds remnants of dark yellowish brown (10YR 4/4) silt loam (Bt); moderate fine and medium subangular blocky structure; friable; few thin clay films on faces of peds; few fine roots; common fine prominent strong brown (7.5YR 5/6) masses of iron accumulation in the matrix; few fine faint light brownish gray (10YR 6/2) iron depletions in the matrix; about 3 percent gravel; neutral; clear wavy boundary. (0 to 10 inches thick.)

2B/E--15 to 22 inches; 60 percent brown (7.5YR 4/4) loam (Bt); moderate fine subangular blocky structure; friable; few distinct strong brown (7.5YR 4/6) clay films on faces of peds; penetrated by tongues of brown (10YR 5/3) loam, (E) very pale brown (10YR 7/3) dry; moderate fine subangular blocky structure; friable; few fine roots; common fine distinct strong brown (7.5YR 5/6) masses of iron accumulation in the matrix; few medium distinct brown (7.5YR 5/2) iron depletions in the matrix; about 3 percent gravel; slightly acid; clear wavy boundary. (Glossic horizon - 4 to 20 inches thick.)

2Bt1--22 to 29 inches; brown (7.5YR 4/4) gravelly loam; moderate medium subangular blocky structure; friable; common distinct brown (7.5YR 4/2) clay films on all faces of peds; few fine roots; common fine distinct strong brown (7.5YR 5/6) masses of iron accumulation in the matrix; common medium distinct brown (7.5YR 5/2) iron depletions in the matrix; about 16 percent gravel and 3 percent cobbles; Moderately acid; clear wavy boundary.

2Bt2--29 to 38 inches; brown (7.5YR 4/4) gravelly clay loam; moderate medium subangular blocky structure; firm; common distinct brown (7.5YR 4/2) clay films on vertical faces of peds; few fine roots; common medium distinct strong brown (7.5YR 5/6) masses of iron accumulation in the matrix; common medium distinct brown (7.5YR 5/2) iron depletions in the matrix; about 20 percent gravel and 10 percent cobbles; moderately acid; clear wavy boundary.

2Bt3--38 to 45 inches; brown (7.5YR 4/4) cobbly loam; weak medium subangular blocky structure; friable; few distinct brown (7.5YR 4/2) clay films on vertical faces of peds; few fine distinct strong brown (7.5YR 5/6) masses of iron accumulation in the matrix; few fine distinct brown (7.5YR 5/2) iron depletions in the matrix; about 20 percent gravel and 20 percent cobbles; moderately acid; clear wavy boundary. (Combined thickness of the 2Bt horizons ranges from 22 to 40 inches.)

2R--45 inches; shattered igneous and metamorphic bedrock with dark brown (7.5YR 4/4) loam in joints more than 4 inches apart that diminish with depth.

TYPE LOCATION: Marathon County, Wisconsin; about 2 1/2 miles northeast of Marathon; 1200 feet east and 1200 feet north of the center of sec. 27, T. 29 N., R. 6 E. USGS Marathon, Wis. Quad. Latitude 44 degrees 58 minutes 8 seconds N. Longitude 89 degrees 46 minutes 25 seconds W. NAD 27.

RANGE IN CHARACTERISTICS: Depth to the base of the argillic horizon ranges from 36 to 60 inches. Thickness of the loess or other silty mantle and depth to the underlying till and residuum ranges from 7 to 15 inches. Depth to lithic contact ranges from 40 to 60 inches. Volume of angular gravel ranges from 0 to 10 percent in the silty mantle, from 3 to 35 percent in the upper part of the till, and from 15 to 60 percent in the lower part of the till. Volume of angular cobbles ranges from 0 to 5 percent in the silty mantle, from 5 to 15 percent in the upper part of the till, and from 5 to 40 percent in the lower part of the till. A stony phase is recognized in some places. Reaction ranges from very strongly acid to neutral in the upper part of the solum and from strongly acid to slightly alkaline in the lower part. Redox accumulatins are commonly throughout the soil below the A horizon. Redox depletions with chroma of 2 or less are within the upper 10 inches of the argillic horizon and saturation occurs there for some time in most years.
The Ap or A horizon has hue of 10YR, value of 3 or 4, and chroma of 2 or 3. Uncultivated pedons have an A horizon with hue of 10YR, value of 2 or 3, and chroma of 1 or 2. Texture of the Ap or A horizon is silt loam.
The E horizon has hue of 10YR, value of 4 to 6, and chroma of 2 or 3. Texture is typically silt loam but where the silty mantle is thin, texture is sandy loam, fine sandy loam, or loam.

In a few pedons, immediately below the Ap or A horizons, there are colors similar to those of a spodic horizon, but such layers are too thin or do not meet the chemical requirements for spodic.

Rietbrock soils have a glossic horizon. Horizonation has a wide range depending on the thickness of the silty mantle and the degree of eluviation. Therefore, there can be E/B, B/E, 2E/B, or 2B/E horizons, singly or in combination.

Typically the E part of the glossic horizon has color like the E horizon described above. Texture is typically silt loam but in pedons where the silty mantle is thin, texture of the 2E part is loam, sandy loam, or the gravelly or cobbly analogs.

The Bt part of the glossic horizon has hue of 5YR or 7.5YR and value and chroma of 3 to 5. Value and chroma of 3 do not occur together. Typically, texture is silt loam but where the silty mantle is thin, texture of the 2B part is loam, clay loam, sandy clay loam, sandy loam or the gravelly or cobbly analogs.

The 2Bt horizon has hue of 2.5YR, 5YR, 7.5YR, 10YR, or 2.5Y; value of 3 to 5; and chroma is 4 to 6. Texture is clay loam, sandy clay loam, loam, or sandy loam or the gravelly or cobbly analogs.

Some pedons have a 2C horizon with color like the 2Bt horizon. Texture is the gravelly, very gravelly, cobbly or very cobbly analogs of sandy loam or loam.

The 2R horizon is igneous or metamorphic bedrock.

COMPETING SERIES: These are the Alstad, Big Iron, Keewatin, Kert, Meadland, Milladore, Nary, Point, and Withee series. None of these soils have a lithic contact.

GEOGRAPHIC SETTING: These soils are on glaciated uplands underlain by bedrock. Slopes are plane and concave and range from 1 to 12 percent. Rietbrock soils formed in thin loess or other silty deposits and in the underlying loamy till and residuum weathered from igneous and metamorphic bedrock. The till is derived mainly from the local residuum. Mean annual precipitation ranges from 28 to 32 inches. Mean annual air temperature ranges from 43 to 45 degrees F.
GEOGRAPHICALLY ASSOCIATED SOILS: These are the Fenwood, Meadland, Milladore, Rozellville, and Sherry soils. The well drained Rozellville soils are on higher lying positions on nearby areas, but are underlain by loamy glacial till and residuum. The well drained Fenwood soils are on higher lying positions and are in a drainage sequence with the Rietbrock soils. The Meadland and Milladore soils are on similar slope positions as the Rietbrock soils, but are underlain by loamy glacial till and residuum and have bedrock at a depth greater than 60 inches. The poorly drained and very poorly drained Sherry soils occupy drainageways adjacent to the Rietbrock soils.

DRAINAGE AND PERMEABILITY: Somewhat poorly drained. The potential for surface runoff ranges from negligible to medium. Permeability is moderate or moderately slow. These soils have a perched seasonal high water table at a depth of 0.5 to 2.5 feet for some time in most years.

USE AND VEGETATION: Cleared areas are used for cropland or pastureland. Common crops are corn, small grains, and hay. Some areas are used for woodland. Native vegetation is mixed deciduous and coniferous forests with white pine, black spruce, eastern hemlock, red maple, quaking aspen, American elm, and white ash predominating.

DISTRIBUTION AND EXTENT: In central Wisconsin, mostly in Marathon, Wood, and Clark Counties and along some large streams in Lincoln County. These soils are moderate in extent.

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

SERIES ESTABLISHED: Wood County, Wisconsin, 1971.

REMARKS: Field experience indicates that these soils have some evidence of till overlying the residuum or a mixture of till and residuum.

Diagnostic horizons and features recognized in the pedon are:
ochric epipedon - 0 to 15 inches (Ap, E, and E/B horizons);
glossic horizon 11 to 22 inches (E/B, 2B/E);
argillic horizon - 15 to 45 inches (2B/E, 2Bt1, 2Bt2, 2Bt3);
aquic feature redox depletions with chroma of 2 or less and saturation in the upper 10 inches of the argillic horizon.

ADDITIONAL DATA: Refer to soil survey sample number 81WI073022 for National Soil Survey Laboratory data on a Rietbrock pedon.


National Cooperative Soil Survey
U.S.A.