LOCATION ROCKMARSH          WI+MN
Established Series
FJS/JJJ
06/2006

ROCKMARSH SERIES


The Rockmarsh series consists of very deep, somewhat poorly drained soils formed in loamy-skeletal and sandy-skeletal alluvium and in dense loamy-skeletal till on flood plains and stream terraces. Permeability is moderate in the loamy skeletal alluvium, rapid in the sandy skeletal alluvium, moderate in the till subsoil, and very slow in the dense till substratum. Slope ranges from 0 to 20 percent. Mean annual precipitation is about 31 inches. Mean annual air temperature is about 42 degrees F.

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

TYPICAL PEDON: Rockmarsh very cobbly silt loam, on a convex, south southeast-facing slope of 2 percent, in a woodland, at an elevation of about 915 feet. (Colors are for moist soil unless otherwise stated.)

Oe--0 to 1 inches; very dark brown (10YR 2/2), very cobbly moderately decomposed plant materials, dark brown (7.5YR 3/2), dry; strong fine and medium lenticular platy structure parting to strong very fine subangular blocky; friable; many very fine to medium roots and common coarse throughout; 30 percent gravel, 20 percent cobbles, and 5 percent stones; strongly acid; clear wavy boundary. (0 to 3 inches thick)

A--1 to 8 inches; dark brown (7.5YR 3/2) very cobbly silt loam, brown (7.5YR 4/2) dry; weak fine and medium subangular blocky structure parting to moderate fine granular; friable; many very fine to medium roots and common coarse throughout; 18 percent gravel, 35 percent cobbles and 5 percent stones; strongly acid; clear wavy boundary. (3 to 9 inches thick)

2Bw--8 to 23 inches; brown (7.5YR 4/3) extremely gravelly loamy coarse sand, light brown (7.5YR 6/3), dry; weak medium subangular blocky structure; very friable; common very fine to medium and few coarse roots; 28 percent gravel, 55 percent cobbles, and 2 percent stones; few fine distinct strong brown (7.5YR 5/6) masses of iron accumulation; moderately acid; gradual wavy boundary. (0 to 20 inches thick)

3Bt--23 to 46 inches; reddish brown (5YR 4/4) extremely gravelly sandy clay loam; strong coarse and very coarse prismatic structure parting to strong fine subangular blocky; friable; few very fine to medium roots; many faint reddish brown (2.5YR 4/4) clay films on faces of peds; 25 percent gravel, 55 percent cobbles and 2 percent stones; common medium prominent dark grayish brown (2.5Y 4/2) iron depletions and many medium distinct yellowish red (5YR 4/6) masses of iron accumulation; moderately acid; gradual wavy boundary. (6 to 35 inches thick)

3Cd--46 to 80 inches; 55 percent dark reddish brown (2.5YR 3/4) and 20 percent pale green (5G 6/2), 15 percent olive brown (2.5Y 4/4), and 10 percent brown (7.5YR 4/4) extremely cobbly sandy loam; massive; firm; 30 percent gravel, 27 percent cobbles, and 10 percent stones; moderately acid.

TYPE LOCATION: Burnett County, Wisconsin; about 10 miles east and 10 miles north of Danbury; located about 1,180 feet east and 1,930 feet north of the southwest corner of section 16, T. 42 N., R. 14 W.; USGS Webb Lake topographic quadrangle; lat. 46 degrees 07 minutes 08 seconds N. and long. 92 degrees 07 minutes 43 seconds W., NAD 83.

RANGE IN CHARACTERISTICS: Depth to the densic contact ranges from 40 to 60 inches. The depth to the top of the argillic horizon ranges from 20 to 40 inches. Weighted average clay content of the particle-size control section ranges from 12 to 25 percent and the weighted average content of fine sand or coarser is greater than 15 percent. The weighted average content of coarse fragments in the particle-size control section ranges from 35 to 85 percent. Volume of gravel ranges from 25 to 45 percent in the surface and subsoil and from 5 to 70 percent in the substratum. Volume of cobbles ranges from 10 to 35 percent throughout. Volume of stones ranges from 0 to 10 percent throughout. Reaction typically ranges from strongly acid to neutral in the solum and from moderately acid to neutral in the substratum.

The Oe horizon has hue of 7.5YR or 10YR, value of 2 to 3, and chroma of 1 or 2.
Some pedons have an Oa horizon with similar colors.

The A horizon has hue of 7.5YR or 10YR, value of 2.5 or 3, and chroma of 1 or 2. Texture is very cobbly silt loam.

Some pedons have a Bw horizon with hue of 7.5YR or 10YR, value of 3 to 4, and chroma of 3 or 4. Texture is the very gravelly, very cobbly, extremely gravelly or extremely cobbly analogs of sandy loam.

The 2Bw horizon has hue of 7.5YR or 10YR, value of 3 to 4, and chroma of 3 or 4. Bw horizons with spodic color do not have an overlying albic horizon or have pH greater than 5.9 or have less than 0.6 percent organic carbon. Texture is the very gravelly, very cobbly, extremely gravelly or extremely cobbly analogs of loamy sand or loamy coarse sand.

The 3Bt horizon has hue of 5YR or 7.5YR, value of 4 to 6, chroma of 3 to 6. Texture is the very gravelly, extremely gravelly, very cobbly, or extremely cobbly analogs of sandy clay loam, sandy loam, or coarse sandy loam.

Some pedons have a 3Btg horizon with textures and colors like the 3Bt horizon except that it has chroma of 1 or 2.

The 3Cd horizon has hue of 2.5YR 5YR, 7.5YR, 10YR, 2.5Y or 5G, value of 3 to 6, and chroma of 2 to 4. Texture is the very gravelly, extremely gravelly, very cobbly or extremely cobbly analogs of loam, sandy loam or fine sandy loam.

COMPETING SERIES: There are no competing series.

GEOGRAPHIC SETTING:
Parent material--loamy-skeletal and sandy skeletal alluvium and dense loamy-skeletal till
Landform--flood plains and stream terraces
Slope--0 to 20 percent
Elevation--800 to 950 feet
Mean annual temperature--39 to 45 degrees F
Mean annual precipitation--28 to 33 inches
Frost-free period--110 to 130 days

GEOGRAPHICALLY ASSOCIATED SOILS: These are the Bigisland, Clemens, Dairyland, and Makwa soils. The somewhat excessively drained Bigisland soils occupy higher, steeply sloping landscape positions. The somewhat poorly drained Clemens soils are on similar landscape positions but are underlain by sandy skeletal deposits. The moderately well drained Dairyland soils have less clay in the control section and occupy slightly higher landscape positions than the Rockmarsh soils. The very poorly drained Makwa soils occupy slightly lower landscape positions than the Rockmarsh soils.

DRAINAGE AND PERMEABILITY: Somewhat poorly drained. Runoff is neglible to low. Permeability is moderate in the loamy-skeletal alluvium, rapid in the sandy-skeletal alluvium, moderate in the till subsoil, and very slow in the dense till substratum. These soils have a perched seasonal high water table at a depth of 1 to 2.5 feet from October to May in normal years. These soils are frequently flooded for brief periods during April in most years, but a non-flooded phase is recognized.

USE AND VEGETATION: Most areas of this soil are in woodland. Native vegetation is mixed deciduous and coniferous forest. Common trees are northern pin oak, white ash, quaking aspen, and red maple.

DISTRIBUTION AND EXTENT: Northwestern Wisconsin and East Central Minnesota. LRR K, MLRA 91B. This soil is of small extent.

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

SERIES ESTABLISHED: Burnett County, Wisconsin, 2004. Source of name is coined from Rock Marsh State Wildlife Area in Pine County, Minnesota.

REMARKS: Diagnostic horizons recognized in this pedon include:
Ochric epipedon--0 to 8 inches (Oe, A );
Argillic horizon--23 to 46 inches (3Bt);
Aquic feature--iron depletions with chroma of 2 or less and saturation within the upper 10 inches of the argillic horizon;
Densic contact--46 inches (3Cd);
Particle-size control section--23 to 43 inches;
Lithologic discontinuities--the upper boundary of the 2Bw at 8 inches and the upper boundary of the 3Bt horizon at 23 inches.

ADDITIONAL DATA: Refer to soil survey sample number 98WI013014 for NSSL data on the typical pedon.


National Cooperative Soil Survey
U.S.A.