LOCATION ISAN MNEstablished Series
TAXONOMIC CLASS: Sandy, mixed, frigid Typic Endoaquolls
TYPICAL PEDON: Isan sandy loam with a concave slope less than 1 percent on an stream terrace. (Colors are for moist soil unless otherwise stated.)
A1--0 to 10 inches; black (N 2/0) sandy loam, very dark gray (10YR 3/1) dry; weak fine subangular blocky structure; friable; many very fine roots; slightly acid; clear wavy boundary.
A2--10 to 14 inches; black (N 2/0) sandy loam, very dark gray (10YR 3/1) dry; weak fine subangular blocky structure; friable; common very fine roots; slightly acid; gradual smooth boundary. (Combined thickness of the A horizon is 8 to 18 inches)
AB--14 to 20 inches; very dark grayish brown (10YR 3/2) loamy sand, dark grayish brown (10YR 4/2) dry; weak very fine subangular blocky structure; very friable: few very fine roots; few black (10YR 2/1) streaks on faces of peds; few fine distinct olive brown (2.5Y 4/3) Fe concentrations; slightly acid; gradual wavy boundary. (0 to 8 inches thick)
Bg--20 to 34 inches; dark grayish brown (2.5Y 4/2) loamy sand; weak fine subangular blocky structure; very friable: about 1 percent gravel; common fine prominent strong brown (7.5YR 5/6) Fe concentrations; slightly acid; clear smooth boundary. (3 to 35 inches thick)
Cg1--34 to 40 inches; grayish brown (2.5Y 5/2) coarse sand: single grain; loose; few fine prominent yellowish brown (10YR 5/6) Fe concentrations; about 3 percent gravel; slightly acid; gradual smooth boundary.
Cg2--40 to 80 inches; grayish brown (2.5Y 5/2) coarse sand; single grain; loose: few fine prominent yellowish brown (10YR 5/6) Fe concentrations; about 2 percent gravel; slightly acid.
TYPE LOCATION: About 1 mile east and 1 mile south of Big Lake, 50 feet north and 100 feet east of southwest corner of sec. 28, T. 33 N., R. 27 W., Sherburne Co., MN.; USGS Big Lake quadrangle; lat. 45 degrees 18 minutes 52 seconds N and long. 93 degrees 42 minutes 57 seconds W., NAD27
RANGE IN CHARACTERISTICS: Free carbonates are below depths of 60 inches. The mollic epipedon ranges from 10 to 24 inches thick. The series control section typically contains less than 5
percent by volume gravel of mixed lithology, but some pedons have as much as 10 percent, mostly in strata. The gravel is mostly less than 5mm in size, and in distinct strata or dispersed throughout the profile. The series control section typically is dominated by medium and coarse sand averaging 15 percent or more coarser than 0.42 mm. (No. 40 sieve).
Some pedons have an O horizon up to 4 inches thick.
The A horizon has hue of 10YR, 2.5Y, 5Y, or is neutral, with value of 2 or 3, and chroma of 0 to 2. It is sandy loam, coarse sandy loam, loamy sand or loamy coarse sand. The AB horizon is loamy sand, loamy coarse sand or sand. The A horizon in some pedons contains sufficient organic matter to be classed as having a mucky modifier. It is moderately acid to neutral.
The Bg horizon has hue of 2.5Y, 5Y, 10YR, or is neutral, with value of 4 or 5, and chroma of 2 or less. It is sand, coarse sand, loamy sand or loamy coarse sand. It ranges from strongly acid to slightly acid.
The Cg horizon has hue of 2.5Y or 5Y, value of 4 to 6, and chroma of 1 or 2. It is sand or coarse sand. Typically it is moderately acid to neutral.
COMPETING SERIES: These are the
Garborg,
Hamar,
Hangaard,
Isanti,
Medano and
Venlo soils. Hamar and Venlo soils have particle-size control sections that do not contain gravel. Isanti and Garborg
soils have 85 percent sand or mone passing the no. 40 size sieve and center on fine sands in the control section. Hangaard soils contain 10 to 35 percent, by volume of rock fragments in the particle-size control section. Medano soils have calcareous sediments throughout the profile.
GEOGRAPHIC SETTING: Isan soils are on plane or concave positions in level to undulating outwash plains, stream terraces, flood plains, and valley trains. Slopes range from 0 to 2 percent. Isan
soils formed in sandy outwash sediments frome the Des Moines Lobe of Late Wisconsinan Age. Mean annual air temperature is 37 to 45 degrees F. Mean annual precipitation is 22 to 34 inches. Frost-free days range from 90 to 145. Elevation above sea level ranges from 700 to 1600 feet.
GEOGRAPHICALLY ASSOCIATED SOILS: These are the Duelm, Glendorado(T), and Hubbard soils. All of these have formed in similar materials and occupy higher positions on the landscape. The Duelm soils are moderately well drained, Glendorado(T) soils are somewhat poorly drained, and the Hubbard, soils are excessively drained.
DRAINAGE AND PERMEABILITY: Poorly and very poorly drained. Surface runoff is negligible. Permeability is moderately rapid in the upper part and rapid in the lower part. This soil has season high saturation at a depth of 0.5 foot during April to June in years of normal precipitation in the poorly drained phase and at the surface on the very poorly drained phase. Ponding may also occur on the very poorly drained phase.
USE AND VEGETATION: Most areas are used for pasture or are cropped tocorn, soybeans, small grains, hay, and truck crops. Native vegetation is grasses and sedges and some willow and alder.
DISTRIBUTION AND EXTENT: Mostly MLRA-91 in central and northern Minnesota. Moderately extensive.
MLRA SOIL SURVEY REGIONAL OFFICE (MO) RESPONSIBLE: St. Paul, Minnesota
SERIES ESTABLISHED: Hennepin County, Minnesota, 1969.
REMARKS: Diagnostic horizons and features recognized in this pedon are: mollic epipedon - the zone from the surface to a depth of 20 inches (A1, A2 and AB horizons); aquic moisture regime - low chroma and redox features below mollic epipedon. Type location moved from Hennepin County, Mn. to Sherburne County, Mn., 11/96 to better exemplify the series concept within the MLRA