LOCATION VASA MNEstablished Series
TAXONOMIC CLASS: Fine-silty, mixed, superactive, mesic Mollic Oxyaquic Hapludalfs
TYPICAL PEDON: Vasa silt loam, on a linear, northeast-facing slope of 3 percent, in a cultivated field, at an elevation of about 360 meters above sea level. (Colors are for moist soil unless otherwise stated.)
Ap--0 to 23 centimeters; very dark brown (10YR 2/2) silt loam, dark grayish brown (10YR 4/2) dry; moderate fine subangular structure parting to weak fine granular; friable; common fine roots; neutral; abrupt smooth boundary. (13 to 23 centimeters thick)
Bt1--23 to 69 centimeters; dark yellowish brown (10YR 4/4) silt loam; moderate fine and medium subangular blocky structure; friable; common fine roots; common faint dark brown (10YR 3/3) clay films on faces of peds; slightly acid; clear wavy boundary.
Bt2--69 to 86 centimeters; yellowish brown (10YR 5/4) silt loam; moderate medium subangular blocky structure; friable; few fine roots; common faint brown (10YR 4/3) clay films on faces of peds; few distinct light brownish gray (10YR 6/2) silt coats on vertical faces of peds; few faint yellowish brown (10YR 5/6) masses of iron accumulation; few distinct grayish brown (10YR 5/2) masses of iron depletion; moderately acid; gradual wavy boundary.
Bt3--86 to 135 centimeters; yellowish brown (10YR 5/4) silt loam; moderate medium subangular blocky structure; friable; few very fine roots; few faint brown (10YR 4/3) clay films on faces of peds; few distinct light brownish gray (10YR 6/2) silt coats on vertical faces of peds; common distinct yellowish brown (10YR 5/8) masses of iron accumulation; common distinct grayish brown (10YR 5/2) masses of iron depletion; moderately acid; abrupt wavy boundary. (Combined thickness of the Bt horizon is 79 to 132 centimeters thick.)
2Bt4--135 to 203 centimeters; yellowish brown (10YR 5/6) loam; weak coarse subangular blocky structure; firm; very few fine roots between ped faces; few distinct dark yellowish brown (10YR 4/6) clay films on ped faces; few faint yellowish brown (10YR 5/8) masses of iron accumulation; few distinct grayish brown (10YR 5/2) masses of iron depletion; about 3 percent gravel; slightly acid.
TYPE LOCATION: Major Land Resource Area (MLRA) 105-Northern Mississippi Valley Loess Hills; Goodhue County, Minnesota subset; about 1/2 mile northwest of northwest Bellechester; located about 2,230 feet east and 245 feet north of the southwest corner of section 29, T. 111 N., R. 14 W.; USGS Goodhue East topographic quadrangle; lat. 44 degrees 23 minutes 01 second N. and long. 92 degrees 31 minutes 22 seconds W., NAD 83.
RANGE IN CHARACTERISTICS:
Depth to glacial till--100 to 200 centimeters
Depth to carbonates--125 to more than 200 centimeters
Clay content of the particle-size control section (weighted average)--20 to 28 percent
Sand content of the particle-size control section (weighted average)--less than 10 percent
Coarse silt to fine silt ratio--about 1 in the upper half of the series control section and increases to about 2 in the lower half of the series control section
Ap or A (when present) horizon:
Hue--10YR
Value--2 or 3, moist and 4 or 5, dry
Chroma--1 to 3
Texture--silt loam
Clay content--15 to 22 percent
Sand content--less than 10 percent
Rock fragment content--0 percent
Reaction--moderately acid to neutral
E horizon (when present):
Hue--10YR
Value--4 or 5
Chroma--2 or 3
Texture--silt loam
Clay content--15 to 22 percent
Sand content--less than 10 percent
Rock fragment content--0 percent
Reaction--moderately acid to neutral
Thickness--0 to 15 centimeters
Bt horizon:
Hue--10YR, upper part and 10YR or 2.5Y, lower part
Value--4 or 5
Chroma--3 to 6
Texture--silt loam or silty clay loam
Clay content--20 to 28 percent
Sand content--less than 10 percent
Rock fragment content--0 percent
Reaction--strongly acid to neutral
B/A clay ratio--1.2 to 1.4
BC or C horizon (when present):
Hue--10YR or 2.5Y
Value--5 or 6
Chroma--3 to 6
Texture--silt loam
Clay content--15 to 22 percent
Sand content--8 to 15 percent
Rock fragment content--0 percent
Reaction--slightly acid or neutral
2Bt horizon:
Hue--10YRor 2.5Y
Value--4 or 5
Chroma--3 to 6
Texture--loam or clay loam
Clay content--20 to 28 percent
Sand content--25 to 45 percent
Rock fragment content--2 to 15 percent
Reaction--strongly acid to neutral
2BC horizon (when present):
Hue--10YR or 2.5Y
Value--4 to 6
Chroma--4 to 8
Texture--loam
Clay content--18 to 27 percent, mean of 22 percent
Sand content--35 to 50 percent, mean of 44 percent
Rock fragment content--2 to 12 percent
Reaction--slightly acid to moderately alkaline
Moist bulk density--1.75 to 1.90 g/cc
COMPETING SERIES: These are the
Barony,
Downsouth,
Grays,
Hedrick,
Juda,
Kaneville,
Newvienna,
Richview,
Throckmorton,
Windere, and
Wingate series.
Barony--have a sand content of more than 15 percent within depths of 51 to 102 centimeters
Downsouth--have a sand content of less than 7 percent and no rock fragments in the lower third of the series control section
Grays--have carbonates within depths of 51 to 102 centimeters
Hedrick--have a sand content of less than 10 percent and no rock fragments in the lower third of the series control section
Juda--have carbonates within depths of 61 to 102 centimeters and have a clay content of 29 to 40 percent in the lower third of the series control section
Kaneville--have strata with more than 45 percent sand in the lower third of the series control section
Newvienna--have a sand content of less than 10 percent and no rock fragments in the lower third of series control section
Richview--are in areas that have a mean annual air temperature range of 12 to 14 degrees C and a mean annual precipitation range of 910 to 1,140 millimeters
Throckmorton--have a sand content of more than 15 percent within depths of 61 to 102 centimeters and have a densic layer in the lower third of the series control section
Windere--have a sand content of more than 15 percent within depths of 56 to 102 centimeters
Wingate--have a sand content of more than 15 percent within depths of 51 to 102 centimeters
GEOGRAPHIC SETTING:
Parent material--100 to 200 centimeters of loess and the underlying glacial till, the loess is Late Wisconsin in age and the glacial till is pre-Wisconsin in age
Landform--interfluves on dissected till plains
Slope--0 to 6 percent
Elevation--305 to 427 meters
Mean annual air temperature--7 to 10 degrees C
Mean annual precipitation--700 to 870 millimeters
Frost-free period--150 to 180 days
GEOGRAPHICALLY ASSOCIATED SOILS: These are the
Downs,
Hersey,
Joy,
Mt. Carroll, and
Ossian soils.
Downs--are at higher elevations on interfluves and side slopes and do not have a frequently saturated zone within a depth of 1.8 meters in normal years
Hersey--are at higher elevations on interfluves and side slopes and have a frequently saturated zone at a depth of 1.0 meter during the wettest period of normal years
Joy--are at lower elevations on headslopes, have a frequently saturated zone at a depth of 0.3 meter during the wettest period of normal years, and have a mollic epipedon
Mt. Carroll--are at higher elevations on interfluves and side slopes and do not have a frequently saturated zone within a depth of 1.8 meters in normal years
Ossian--are at lower elevations on upland drainageways, have a frequently saturated zone at the soil surface during the wettest portions of normal years, and have a mollic epipedon
DRAINAGE AND SATURATED HYDRAULIC CONDUCTIVITY:
Drainage class--moderately well drained--a frequently saturated zone occurs at a depth of 0.75 meter during April to June in normal years
Saturated hydraulic conductivity--4.23 to 14.11 micrometers per second (moderately high) in the loess and 0.01 to 1.41 micrometers per second (low or moderately low) in the glacial till
Surface runoff potential--negligible to low
USE AND VEGETATION:
Most areas are cultivated. The principal crops are corn, small grains, soybeans, and hay. The native vegetation is big bluestem, little bluestem, switchgrass, other grasses of the tall grass prairie and mixed deciduous trees.
DISTRIBUTION AND EXTENT:
Physiographic Division--Interior Plains
Physiographic Province--Central Lowland
Physiographic sections--Wisconsin driftless section and Dissected till plains
MLRAs--Eastern Iowa and Minnesota Till Prairies (104) and Northern Mississippi Valley Loess Hills (105)
LRR M; southeastern Minnesota and southwestern Wisconsin
Extent--moderate
MLRA SOIL SURVEY REGIONAL OFFICE (MO) RESPONSIBLE: St. Paul, Minnesota
SERIES ESTABLISHED: Goodhue County, Minnesota, 1972.
REMARKS:
Particle-size control section--the zone from a depth of 23 to 73 centimeters (Bt1 and Bt2 horizons);
series control section--the zone from the surface to a depth of 200 centimeters (Ap, Bt1, Bt2, Bt3, and 2Bt4 horizons).
Diagnostic horizons and features recognized in this pedon include:
ochric epipedon--the zone from the surface to a depth of 23 centimeters (Ap horizon);
argillic horizon--the zone from a depth of 23 to 203 centimeters (Bt1,Bt2, Bt3, and 2Bt4 horizons);
udic moisture regime.
Some pedons have vertical seams or wedges of sand or loamy sand about 5 to 30 centimeters wide and about 0.9 to 1.2 meters deep extending downward from the stone line into the glacial till.
Cation-exchange activity class is inferred from lab data from similar soils in the surrounding area.
Taxonomy version--Keys to Soil Taxonomy, tenth edition, 2006.
ADDITIONAL DATA: Refer to Minnesota Agricultural Experiment Station Control File Code No. 1278 for results of some laboratory analyses of the typifying pedon and to No. 8 for results of analyses of an additional pedon.