LOCATION BASSETT                 IA

Established Series
Rev. JDH-LDC-AAC
08/2013

BASSETT SERIES

The Bassett series consists of very deep, moderately well drained soils formed in 30 to 75 centimeters of silty or loamy sediments and the underlying till. These soils are on interfluves and side slopes on dissected till plains on the Iowan Erosion Surface. Slope ranges from 2 to 35 percent. Mean annual air temperature is about 8 degrees C. Mean annual precipitation is about 885 millimeters.

TAXONOMIC CLASS: Fine-loamy, mixed, superactive, mesic Mollic Hapludalfs

TYPICAL PEDON: Bassett loam, on a southwest-facing, convex slope of about 3 percent, in a cultivated field. (Colors are for moist soil unless otherwise stated.)

Ap--0 to 23 centimeters; very dark grayish brown (10YR 3/2) loam, grayish brown (10YR 5/2), dry; weak fine granular structure; friable; common very dark brown (10YR 2/2) organic stains on all faces of peds; slightly acid, pH 6.3; clear smooth boundary. (13 to 25 centimeters thick)

BE--23 to 43 centimeters; brown (10YR 4/3) loam; weak fine subangular blocky structure; friable; few very dark grayish brown (10YR 3/2) organic stains on all faces of peds; very strongly acid, pH 4.7; clear smooth boundary. (0 to 20 centimeters thick)

2Bt1--43 to 64 centimeters; yellowish brown (10YR 5/6) loam; weak fine prismatic structure parts to weak medium subangular blocky structure; friable; few very dark grayish brown (10YR 3/2) clay films on surfaces along root channels and pores and few brown (10YR 5/3) clay films on all faces of peds; 1 percent mixed rock fragments (2 to 75 millimeters in diameter); very strongly acid, pH 4.7; gradual smooth boundary.

2Bt2--64 to 86 centimeters; yellowish brown (10YR 5/6) loam; weak fine prismatic structure parts to moderate medium subangular blocky structure; firm; few distinct dark brown (10YR 3/3) clay films on all faces of peds and root channels; few faint brown (10YR 5/3) clay films on all faces of peds and; 2 percent mixed rock fragments (2 to 75 millimeters in diameter); strongly acid, pH 5.3; gradual smooth boundary.

2Bt3--86 to 117 centimeters; yellowish brown (10YR 5/6) loam; few distinct dark grayish brown (10YR 4/2) iron depletions throughout; weak medium prismatic structure; firm; few prominent very dark grayish brown (10YR 3/2) clay films on surfaces along pores and root channels; 1 percent mixed rock fragments (2 to 75 millimeters in diameter); moderately acid, pH 5.8; gradual smooth boundary; clear wavy boundary (Combined thickness of the 2Bt horizons is 71 to 160 centimeters.).

2BC--117 to 152 centimeters; yellowish brown (10YR 5/6) loam; few prominent grayish brown (2.5Y 5/2) iron depletions; weak very coarse subangular blocky structure; firm; few moderately cemented carbonate masses; 1 percent mixed rock fragments (2 to 75 millimeters in diameter); strong effervescence; slightly alkaline, pH 7.6.

TYPE LOCATION: Major Land Resource Area (MLRA) 104-Eastern Iowa and Minnesota Till Prairies, Butler County, Iowa subset; about 10 miles west of the town of Lime Springs; located about 1920 feet south and 1820 feet west of the northeast corner of section 25, T. 92 N., R. 16 W.; USGS Clarksville topographic quadrangle; lat. 42 degrees 45 minutes 19.4 seconds N. and long. 92 degrees 40 minutes 39.4 seconds W., WGS 84. UTM Coordinates 4,733,702 N and 526, 381 W and decimal degrees coordinates 42.7553889 N; -92.6776111 W.

RANGE IN CHARACTERISTICS:
Depth to till--30 to 75 centimeters
Depth to carbonates--100 to 152 centimeters
Clay content in the particle-size control section (weighted average)--20 to 28 percent
Sand content in the particle-size control section (weighted average)--30 to 70 percent
Special feature--some pedons have a stone line or thin layer, 2 to 13 centimeters thick of gravelly and sandy materials at the base of the silty or loamy sediments

A or Ap horizon:
Hue--10YR
Value--2 or 3
Chroma1 to 3
Texture--loam or silt loam
Clay content--14 to 26 percent
Sand content--10 to 40 percent
Rock fragment content--1 to 10 percent
Reaction--strongly acid to neutral (5.1 to 7.3)
Special features--when mixed to a depth of 18 centimeters, matrix value is 3 or less, moist, 5 or less, dry

E horizon (when present):
Hue--10YR
Value--3 to 5
Chroma--2 or 3
Texture--loam or silt loam
Clay content--15 to 26 percent
Sand content--10 to 50 percent
Rock fragment content--1 to 10 percent
Reaction--very strongly acid to neutral (4.5 to 7.3)

In some cultivated areas the E horizon is mixed in the Ap horizon

BE horizon (when present):
Hue--7.5YR or 10YR
Value--4 or 5
Chroma--3 to 6
Texture--loam or silt loam
Clay content--15 to 25 percent
Sand content--10 to 50 percent
Rock fragment content--1 to 10 percent
Reaction--very strongly acid to slightly acid (4.5 to 6.5)

In some pedons the BE horizon extends into the underlying till and may have fine faint accumulations of high chroma

2Bt horizon:
Hue--7.5YR to 5Y
Value--4 to 8
Chroma--1 to 8
Texture--loam, clay loam or sandy clay loam
Clay content--20 to 28 percent
Sand content--30 to 70 percent
Rock fragment content--2 to 15 percent
Reaction--very strongly acid to slightly acid (4.5 to 6.5)
Low chroma matrix or redoximorphic depletions occur in the lower parts of this horizon

2BC horizons:
Hue--7.5YR to 5Y
Value--4 to 8
Chroma--1 to 8
Texture--loam
Clay content--18 to 27 percent, mean of 23 percent
Sand content--30 to 50 percent, mean of 44 percent
Rock fragment content--2 to 12 percent
Reaction--moderately acid to moderately alkaline (5.6 to 7.3)
Moist bulk density--1.75 to 1.9 gm/cc

COMPETING SERIES: These are the Angus, Argyle, Blooming, Caleb, Cortland, Gara, Koronis, Lester, Newcomer, Orwood, Racine, Sebbo, Taopi, Waucoma, and Winneshiek series.
Angus--have carbonates within a depth of 137 centimeters and have a sand content of 30 to 45 percent throughout the series control section
Argyle--have matrix hues of 5YR or redder in the lower half of the series control section
Blooming--have a moist bulk density of less than 1.75 gm/cc in the lower third of the series control section
Caleb--have a moist bulk density of less than 1.75 gm/cc in the lower third of the series control section
Cortland--have a moist bulk density of less than 1.75 gm/cc in the lower third of the series control section and are in areas that have a mean annual air temperature range of 10 to 12 degrees C
Gara--have a clay content of 32 to 35 percent in the particle-size control section
Koronis--have carbonates within a depth of 91 centimeters and have a sand content of 50 to 70 percent in the lower third of the series control section
Lester--have carbonates within a depth of 137 centimeters and have a moist bulk density of less than 1.75 gm/cc in the lower third of the series control section
Newcomer--have a paralithic contact with sandstone within a depth of 102 centimeters
Orwood--have a sand content of 15 to 45 percent in the particle-size control section and do not have rock fragments in the series control section
Racine--do not have a frequently saturated zone within a depth of 1.8 meters in normal years
Sebbo--have a frequently saturated zone at a depth of 1 meter during the wettest periods of normal years and have 0 to 15 percent sandstone channers and chert gravel throughout the series control section
Taopi--have carbonates within a depth of 102 centimeters and have soft limestone or siltstone rock fragment content of 10 to 40 percent in the lower third of the series control section
Waucoma--have a lithic contact with limestone within a depth of 152 centimeters
Winneshiek--have a lithic contact with limestone within a depth of 102 centimeters

GEOGRAPHIC SETTING:
Parent material--30 to 75 centimeters of silty or loamy sediments and the underlying till
Landform--interfluves and side slopes on dissected till plains on the Iowan Erosion Surface
Slope--2 to 35 percent
Elevation--259 to 488 meters above sea level
Mean annual air temperature--7 to 11 degrees C
Mean annual precipitation--735 to 965 millimeters
Frost-free period--160 to 205 days

GEOGRAPHICALLY ASSOCIATED SOILS: Members of the typical catena include Kasson, Oran, Racine, and Skyberg soils.
Kasson--are at lower elevations on side slopes and have a saturated zone at a depth of 0.7 meter during the wettest periods of normal years
Oran--are at lower elevations on base slopes adjacent to drainageways and have a saturated zone at a depth of 0.4 meter during the wettest periods of normal years
Racine--are on higher elevations on shoulders and narrow summits and are not saturated within 1.8 meters in normal years
Skyberg--are at lower elevations in flat to concave drainageways and have a saturated zone at the soil surface during the wettest periods of normal years

DRAINAGE AND SATURATED HYDRAULIC CONDUCTIVITY:
Drainage class--moderately well drained--a saturated zone occurs between depths of 1 to 1.8 meters during March to June when precipitation is within one standard deviation of the 30 year mean of annual precipitation and both perched and apparent saturation can occur on this soil based on the season and intensity of rainfall during a given period of time
Saturated hydraulic conductivity--1.0 to 10.0 micrometers per second in the silty or loamy sediments and 0.01 to 1.0 micrometers per second in the till
Surface runoff potential--negligible to high

USE AND VEGETATION:
Most areas are cultivated. The principal crops are corn, soybeans, small grains, and legume 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 section--Dissected till plains
MLRAs--Eastern Iowa and Minnesota Till Prairies (104) and Illinois and Iowa Deep Loess and Drift (108)
Local physiographic area--Iowa Erosion Surface
LRR M; northeastern Iowa and possibly southeastern Minnesota
Extent--large

MLRA SOIL SURVEY REGIONAL OFFICE (MO) RESPONSIBLE: Indianapolis, Indiana

SERIES ESTABLISHED: Iowa County, Iowa, 1965.

REMARKS:
Particle-size control section--the zone from a depth of 43 to 93 centimeters (2Bt1, 2Bt2 and 2Bt3 horizons);
series control section--the zone from the surface to a depth of 150 centimeters (Ap, BE, 2Bt1, 2Bt2, 2Bt3, and 2BC 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 43 to 117 centimeters (2Bt1, 2Bt2, and 2Bt3 horizons);
udic moisture regime.

Not all pedons meet the requirements of an argillic horizon (1.2 times clay increase from BE horizon to 2Bt horizon). In these cases, the plow layer (Ap horizon) extends to the argillic horizon without transitional layers.

Some pedons have vertical seams or wedges of sand or loamy sand about 5 to 15 centimeters wide and about 0.9 to 1.2 meters deep extending downward from the stone line into the till.

Mollic subgroup based on colors and thickness of the ochric epipedon.

Cation-exchange activity class is inferred from lab data from similar soils in the surrounding area.

Official Series Description Type Location moved (08/2013) due to previous site (site id-1965IA089001) classifying as Fine-loamy, mixed, superactive, mesic Oxyaquic Hapludalfs

Taxonomy version--Keys to Soil Taxonomy, eleventh edition, 2010.

The MLRA 104 Steering Committee approved property edits to this series in February 2004.

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National Cooperative Soil Survey
U.S.A.