LOCATION GALVA              IA+MN

GALVA SERIES

TAXONOMIC CLASS: Fine-silty, mixed, superactive, mesic Typic Hapludolls

TYPICAL PEDON: Galva silty clay loam, on a convex slope of 4 percent, in a cultivated field. (Colors are for moist soil unless otherwise stated.)

Ap--0 to 15 centimeters (0 to 6 inches); very dark brown (10YR 2/2) silty clay loam, very dark grayish brown (10YR 3/2) dry; weak fine granular structure; friable; slightly acid; abrupt smooth boundary.

A--15 to 28 centimeters (6 to 11 inches); about 90 percent very dark brown (10YR 2/2) and about 10 percent very dark grayish brown (10YR 3/2) silty clay loam, very dark grayish brown (10YR 3/2) dry; moderate fine granular and very fine subangular blocky structure; friable; slightly acid; clear smooth boundary. [Combined thickness of the A horizon is 25 to 41 centimeters (10 to 16 inches).]

BA--28 to 43 centimeters (11 to 17 inches); dark brown (10YR 3/3) silty clay loam, brown (10YR 5/3) dry; weak fine granular and very fine subangular blocky structure; friable; about half of the peds have very dark grayish brown (10YR 3/2) coatings on peds; neutral; gradual smooth boundary. [0 to 20 centimeters (0 to 8 inches) thick]

Bw1--43 to 58 centimeters (17 to 23 inches); brown (10YR 4/3) silty clay loam; weak medium subangular blocky structure parting to weak very fine subangular blocky; friable; few very dark grayish brown (10YR 3/2) coatings on peds; neutral; gradual smooth boundary.

Bw2--58 to 79 centimeters (23 to 31 inches); brown (10YR 4/3) silty clay loam; weak fine and medium subangular blocky structure parting to weak very fine subangular blocky; friable; neutral; gradual smooth boundary.

Bw3--79 to 114 centimeters (31 to 45 inches); brown (10YR 4/3) silt loam; weak fine and medium subangular blocky structure parting to weak very fine subangular blocky; friable; few fine distinct gray (10YR 5/1) redoximorphic depletions; neutral; abrupt smooth boundary. [Combined thickness of the Bw horizon is 51 to 114 centimeters (20 to 45 inches).]

BC--114 to 152 centimeters (45 to 60 inches); yellowish brown (10YR 5/4) silt loam; weak fine and medium subangular blocky structure parting to weak very fine subangular blocky, grading to massive in lower part; friable; few fine soft calcium carbonate accumulations and few calcium carbonate concretions; few dark oxide stains; few fine distinct gray (10YR 5/1) redoximorphic depletions and few fine prominent strong brown (7.5YR 5/6) redoximorphic concentrations; strongly effervescent; moderately alkaline.

TYPE LOCATION: Major Land Resource Area (MLRA) 107A; O'Brien County, Iowa; about 1 mile south and 2 miles west of Paullina; about 323 meters (1,060 feet) west and 58 meters (190 feet) south of the northeast corner of section 18, T. 94 N., R. 41 W.

RANGE IN CHARACTERISTICS:
Depth to carbonates--81 to 183 centimeters (32 to 72 inches)
Thickness of mollic epipedon--25 to 61 centimeters (10 to 24 inches)
Content of clay in the particle-size control section (weighted average)--27 to 35 percent
Content of sand in the particle-size control section (weighted average)--1 to 6 percent fine sand and sand coarser than fine sand

Ap or A horizon:
Hue--10YR
Value--2
Chroma--1 or 2
Texture--silty clay loam
Clay content--34 to 39 percent
Sand content--1 to 10 percent
Reaction--strongly acid to slightly acid

AB horizon (if it occurs):
Hue--10YR
Value--3
Chroma--2 or 3
Texture--silty clay loam
Clay content--34 to 39 percent
Sand content--1 to 10 percent
Reaction--moderately acid or slightly acid
Thickness--0 to 25 centimeters (0 to 10 inches)

BA horizon (where present):
Hue--10YR
Value--3 or 4
Chroma--3
Texture--silty clay loam
Clay content--30 to 39 percent
Sand content--1 to 6 percent
Reaction--slightly acid or neutral

Bw horizon:
Hue--10YR
Value--4 or 5
Chroma--3 or 4
Texture--silty clay loam in the upper part, and silt loam in the lower part
Clay content--27 to 35 percent
Sand content--1 to 6 percent
Reaction--slightly acid or neutral

Note: few or common grayish redoximorphic depletions are below a depth of 76 centimeters (30 inches)

BC horizon (where present):
Hue--10YR
Value--4 or 5
Chroma--3 or 4
Texture--silty clay loam or silt loam
Clay content--25 to 30 percent
Sand content--1 to 10 percent
Reaction--neutral to moderately alkaline

C horizon (where present):
Hue--10YR or 2.5Y
Value--4 to 6
Chroma--1 to 8
Texture--silt loam
Clay content--20 to 27 percent
Sand content--1 to 10 percent
Reaction--neutral to moderately alkaline in the upper part and slightly alkaline or moderately alkaline in the lower part

Some pedons have gravelly sediments below a depth of 60 inches

Some pedons have loamy glacial till below a depth of 60 inches

COMPETING SERIES: These are the Annieville, Biggsville, Dinsmore, Exira, Keg, Marshall, Monona, Northboro, Ponca, Port Byron, Raddle, Salix, and Truman series.
Annieville--have a sand content of more than 10 percent in the lower third of the series control section
Biggsville--have a clay content of 18 to 27 percent in the particle-size control section and have a saturated zone between depths of 1.2 to 1.8 meters (4 to 6 feet) from December to June in most years
Dinsmore--have a sand content of 30 to 70 percent in the lower third of the series control section
Exira--have many or common redoximorphic features within a depth of 76 centimeters (30 inches)
Keg--have a sand content of 10 to 35 percent in the lower half of the series control section
Marshall--do not have carbonates within a depth of 183 centimeters (72 inches)
Monona--have a clay content of 20 to 30 percent in the particle-size control section and do not have a saturated zone within a depth of 1.8 meters (6 feet)
Northboro--have a cambic horizon with matrix color hues of 5YR or 7.5YR
Ponca--have a mollic epipedon 18 to 25 centimeters (7 to 10 inches) thick and have a depth to carbonates range of 36 to 61 centimeters (14 to 24 inches)
Port Byron--have 18 to 27 percent clay in the particle-size control section and have a reaction range of moderately acid to neutral in the cambic horizon
Raddle--have 18 to 24 percent clay in the particle-size control section and have an irregular decrease in clay with increasing depth
Salix--have a sand content of 15 to 60 percent in the lower third of the series control section and have a depth to carbonates range of 51 to 91 centimeters (20 to 36 inches)
Truman--have more than 10 percent sand in the series control section

GEOGRAPHIC SETTING:
Parent material--loess
Landform--uplands and loess covered stream terraces
Slopes--0 to 15 percent
Elevation--366 to 457 meters (1,200 to 1,500 feet) above sea level
Mean annual air temperature--8 to 9 degrees C (46 to 48 degrees F)
Mean annual precipitation--66 to 71 centimeters (26 to 28 inches)
Frost-free period--145 to 175 days

GEOGRAPHICALLY ASSOCIATED SOILS: These are the Afton, Marcus, Primghar, and Sac soils.
Afton--are at lower elevations in drainageways and have mollic epipedons that are 61 to 81 centimeters (24 to 32 inches) thick
Marcus--are at lower elevations in swales or at higher elevations on upland flats and have a saturated zone within a depth of 0.3 meters (1 foot) during the wettest period of most years
Primghar--are at lower elevations in swales or at higher elevations on upland flats and have a saturated zone within depths of 0.3 to 1 meters (1 to 3.5 feet) during the wettest period of most years
Sac--are on landform positions similar to those of the Galva soils and have glacial till within a depth of 102 centimeters (40 inches)

DRAINAGE AND PERMEABILITY:
Drainage class--well drained--a saturated zone does not occur within a depth of 1.8 meters (6 feet) during April to June in most years
Saturate hydraulic conductivity--moderately high
Surface runoff potential--negligible to medium

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, indiangrass, switchgrass, and other grasses of the tall grass prairie.

DISTRIBUTION AND EXTENT:
Physiographic Division--Interior Plains
Physiographic Province--Central Lowland
Physiographic section(s)--Western lake section and Dissected till plains
MLRA--Till Plains (102B) and Iowa and Minnesota Loess Hills (107)
LRR M; northwest Iowa and southwest Minnesota
Extent--large

MLRA OFFICE RESPONSIBLE: St. Paul, Minnesota

SERIES ESTABLISHED: Clay County, Iowa, 1970.

REMARKS:
Particle-size control section--the zone from a depth of 25 to 100 centimeters (10 to 40 inches) (A, BA, Bw1, Bw2, and Bw3 horizons);
series control section--the zone from the surface to a depth of 150 centimeters (0 to 60 inches) (Ap, A, BA, Bw1, Bw2, Bw3, and BC horizons).

Diagnostic horizons and features recognized in this pedon:
mollic epipedon--the zone from the surface to a depth of 43 centimeters (0 to 17 inches) (Ap, A, and BA horizons);
cambic horizon--the zone from a depth of 43 to 152 centimeters (17 to 60 inches) (Bw1, Bw2, Bw3, and BC horizons);
udic moisture regime.

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

Taxonomy version-- Keys to Soil Taxonomy, ninth edition, 2003.

ADDITIONAL DATA:
Published data are available for the Galva series. See Foth, H. D. and Riecken, F. F., 1954. The Galva and Moody Series of Northwestern Iowa, Soil Survey Soc. Amer. Proc. 18; 206-211.