LOCATION DORERTON MN+IA WIEstablished Series
TAXONOMIC CLASS: Loamy-skeletal, mixed, active, mesic Typic Hapludalfs
TYPICAL PEDON: Dorerton loam with a convex 35 percent north-facing slope in dissected uplands in a deciduous forest. (Colors are for moist conditions unless otherwise stated.)
A--0 to 3 inches; very dark brown (10YR 2/2) loam, grayish brown (10YR 5/2) dry; moderate fine granular structure; very friable; abundant roots; slightly acid; abrupt smooth boundary. (3 to 6 inches thick)
E1--3 to 5 inches; dark grayish brown (10YR 4/2) loam; grayish brown (10YR 5/2) dry; weak fine subangular blocky structure; very friable; many very dark grayish brown (10YR 3/2) worm casts; many very fine through medium tubular pores; common roots; strongly acid; abrupt wavy boundary.
E2--5 to 10 inches; brown (10YR 4/3) loam; brown (10YR 5/3) dry; weak medium platy structure; very friable; many very fine through large tubular pores; common roots; strongly acid; clear irregular boundary. (4 to 16 inches, combined thickness of E horizon)
BE--10 to 15 inches; brown (10YR 5/3) loam; moderate medium sub- angular blocky structure; friable; many very fine through medium tubular pores; few roots; many thin coatings of clean silt and sand particles on faces of peds; strongly acid; clear wavy boundary. (0 to 14 inches thick)
Bt1--15 to 18 inches; brown (7.5YR 4/4) loam; moderate medium subangular blocky structure; firm; common medium tubular pores; many faint dark brown (7.5YR 3/2) clay films on the faces of peds; slightly acid; abrupt wavy boundary. (0 to 6 inches thick)
2Bt2--18 to 30 inches; brown (7.5YR 4/4) very channery clay loam; strong medium subangular blocky structure; firm; about 50 percent dolostone fragments of pebble through flagstone size; many distinct dark brown (7.5YR 3/2) clay films on faces of peds; slightly acid; clear irregular boundary. (6 to 20 inches thick)
2C--30 to 60 inches; very pale brown (10YR 7/3) extremely flaggy loamy sand; single grain; loose; about 75 percent dolostone fragments of pebble through flagstone size; strongly effervescence; slightly alkaline
TYPE LOCATION: Olmsted County, Minnesota; 5 miles north of Rochester, Minnesota; 800 feet north and 1,700 feet west of the southeast corner of sec. 11, T. 108 N., R. 14 W.
RANGE IN CHARACTERISTICS: The thickness of the solum is 24 to 45 inches. Depth to free carbonates (in the fine-earth fraction) is 16 to 45 inches. Thickness of the upper mantle is 10 to 24 inches. Coarse fragments typically are lacking in the upper part of the solum, but has as much as 10 percent in some pedons. Coarse fragments of limestone or dolostone pebble, flagstone or cobblestone size comprise 35 to 80 percent of the 2B and 2C horizons. Bedrock commonly begins at depths ranging from 45 to 70 inches. These soils are near or at wilting point for as much as 1 month during July and August in some years.
The A horizon has hue of 10YR, value of 2 or 3, and chroma of 1 or 2. It is strongly acid to neutral. The A horizon is sandy loam, fine sandy loam, loam, or silt loam.
The E horizon has hue of 10YR, value of 3 through 5, and chroma of 2 or 3. It is strongly acid to neutral. The E horizons are sandy loam, fine sandy loam, loam, or silt loam.
The Bt horizon has hue of 10YR or 7.5YR, value of 3 through 5, and chroma of 3 or 4. It is loam, silt loam, silty clay loam, or clay loam. It is strongly acid to neutral.
The 2Bt horizon has hue of 7.5YR or 10YR, value of 4 or 5, and chroma of 3 or 4. It has a fine-earth fraction of loam or clay loam with 20 to 35 percent clay. It has common or many faint through prominent clay films on faces of peds. It is moderately acid to neutral.
The 2C horizon has hue of 10YR, value of 4 through 7, and chroma of 3 through 6. It has a fine-earth fraction of sand, fine sand, loamy sand, loamy fine sand, sandy loam, fine sandy loam, or loam. It is mildly or moderately alkaline.
COMPETING SERIES: These are the Conotton, Hawksbill, Leoni, Lutzke and Oakhill series in the same family and the Frontenac and Nordness series. Conotton soils formed in glacial outwash and are acid to depths of 50 inches or more. The Hawksbill and Leoni soils lack an upper mantle that is free of coarse fragments and lack limestone bedrock within depths of 70 inches. Frontenac soils have a fine-loamy B horizon with less than 35 percent coarse fragments and have a mollic epipedon. Nordness soils have limestone bedrock beginning with depths of 20 inches.
GEOGRAPHIC SETTING: The Dorerton soils have plane or convex slopes with gradient of 12 to 65 percent on sideslopes, upper backslopes and shoulders in dissected uplands. Slopes are 50 to 600 feet in length. Slope aspect is northwest to northeast in most broad valleys and includes southwest to southeast aspects in narrow ravines. Relative relief is 100 to 400 feet. These soils formed in a loamy mantle of loess and erosional sediments and in loamy-skeletal material from fragmented limestone. This overlies sandy-skeletal material from fragmented dolostone or limestone. Dolostone or limestone bedrock underlies this material at depths of 45 to 70 inches or more. Mean annual precipitation is 27 to 35 inches, and mean annual temperature is 45 to 51 degrees F.
GEOGRAPHICALLY ASSOCIATED SOILS: These are the Brodale, Dubuque, Frontenac, Marlean, and Seaton soils. Brodale soils are downslope on steep and very steep south to west-facing back slopes. They have a mollic epipedon and lack an argillic horizon. Dubuque soils are upslope on nose and summit positions, lack coarse fragments, and have a lithic contact beginning between depths of 20 to 40 inches. Frontenac soils are formed in a thicker loamy mantle and are downslope on foot slopes. Marlean soils have a mollic epipedon, lack an argillic horizon, and are principally on north to east-facing back slopes. Seaton soils are typically on summits and formed in loess.
DRAINAGE AND PERMEABILITY: Well drained. Permeability is moderately slow to moderately rapid in the loamy mantle and is moderate to rapid in the underlying loamy-skeletal material (2C horizon).
USE AND VEGETATION: Dorerton soils are used principally for growing trees. Some areas are pastured. Native vegetation is mixed deciduous forest with northern red oak, white oak, burr oak, and aspen being the dominant species.
DISTRIBUTION AND EXTENT: Southeastern Minnesota and west central Wisconsin. It is of moderate extent.
MLRA SOIL SURVEY REGIONAL OFFICE (MO) RESPONSIBLE: St. Paul, Minnesota
SERIES ESTABLISHED: Olmsted County, Minnesota, 1978.
REMARKS: Diagnostic horizons and features recognized in this pedon are: ochric epipedon - the zone from the surface to a depth of 10 inches (A and E horizons); argillic horizon the zone from about 15 to 30 inches (Bt and 2Bt horizons); udic moisture regime.