LOCATION TILFER             IA+MN

TILFER SERIES

TAXONOMIC CLASS: Fine-loamy, mixed, superactive, calcareous, mesic Typic Endoaquolls

TYPICAL PEDON: Tilfer silty clay loam, on a nearly level slope, in a flood plain, in a cultivated field. (Colors are for moist soil unless otherwise stated.)

Ap--0 to 20 centimeters; black (N 2/0) silty clay loam, black (10YR 2/1) dry; moderate medium and fine granular structure; friable; strongly effervescent; slightly alkaline; clear smooth boundary.

A--20 to 48 centimeters; black (N 2/0) silty clay loam, very dark gray (10YR 3/1) dry; weak medium subangular blocky structure parting to weak medium granular; friable; few fine prominent olive (5Y 5/3) redoximorphic concentrations in the lower 8 centimeters; slightly effervescent; slightly alkaline; clear wavy boundary.

Bg--48 to 69 centimeters; light olive gray (5Y 6/2) loam; weak medium subangular blocky structure; friable; accumulations of black (10YR 2/1) loam in some root channels; few fine prominent yellowish brown (10YR 5/6) redoximorphic concentrations; slightly effervescent; slightly alkaline; gradual smooth boundary

BCg--69 to 89 centimeters; olive gray (5Y 5/2) loam; weak coarse subangular blocky structure; friable; few fine prominent strong brown (7.5YR 5/6) redoximorphic concentrations; few small rounded limestone pebbles and a few small granitic pebbles; slightly effervescent; slightly alkaline; abrupt wavy boundary.

2R--89 centimeters; hard, fractured limestone bedrock.

TYPE LOCATION: Major Land Resource Area (MLRA) 104-Eastern Iowa and Minnesota Till Prairies, Worth County, Iowa subset; about 2 miles east and 1 mile south of Kensett; located about 1,000 feet east and 95 feet north of the southwest corner of section 36, T. 99 N., R. 20 W.; USGS Manly topographic quadrangle; lat. 43 degrees 20 minutes 33.8 seconds N. and long. 93 degrees 9 minutes 26.4 seconds W., NAD 83.

RANGE IN CHARACTERISTICS:
Depth to bedrock--50 to 100 centimeters
Depth to carbonates--0 to 10 centimeters
Calcium carbonate equivalent--5 to 30 percent
Clay content in the particle-size control section (weighted average)--24 to 30 percent
Sand content in the particle-size control section (weighted average)--greater than 15 percent fine sand or coarser

Ap or A horizon:
Hue--10YR or is neutral
Value--2
Chroma--0 or 1
Texture--silty clay loam, clay loam, or loam
Clay content--22 to 32 percent
Sand content--10 to 40 percent
Reaction--pH 7.4 to 8.4
Thickness--30 to 50 centimeters

Some pedons have an AB horizon 8 to 15 centimeters thick

Bg horizon:
Hue--2.5Y or 5Y
Value--4 to 6
Chroma--1 or 2
Texture--loam, clay loam, or silty clay loam
Clay content--16 to 30 percent
Sand content--10 to 40 percent
Reaction--pH 7.4 to 8.4
Thickness--10 to 30 centimeters

BCg horizon:
Hue--2.5Y or 5Y
Value--4 to 6
Chroma--1 to 3
Texture--loam or sandy loam
Clay content--10 to 20 percent
Sand content--40 to 70 percent
Reaction--pH 7.4 to 8.4
Thickness--0 to 25 centimeters

2BCg horizon:
Hue--10YR to 5Y
Value--4 to 6
Chroma--1 to 6
Texture--sand, loamy sand, or the gravelly analogs of these textures
Clay content--less than 10 percent
Sand content--75 to 95 percent
Rock fragment content--10 to 30 percent, pebbles and cobbles
Reaction--pH 7.4 to 8.4
Thickness--0 to 15 centimeters

COMPETING SERIES: These are the Canisteo, Hetz, Hooppole, Jeffers, and Kish series.
None of these series have limestone bedrock within a depth of 100 centimeters

GEOGRAPHIC SETTING:
Parent material--50 to 100 centimeters of loamy and silty alluvial sediments overlying limestone bedrock
Landform--low stream terraces and floodplains in river valleys
Slope--0 to 2 percent
Elevation--300 to 400 meters above sea level
Mean annual air temperature--6 to 10 degrees C
Mean annual precipitation--585 to 940 millimeters
Frost-free period--155 to 200 days

GEOGRAPHICALLY ASSOCIATED SOILS: These are the Faxon, Harcot, Kensett, and Marshan series.
Faxon--are on landscape positions similar to those of the Tilfer soils and do not have carbonates in all parts between depths of 25 and 50 centimeters
Harcot--are on landscape positions similar to those of the Tlfer soils and have a sand content of more than 75 percent in the lower part of the particle-size control section
Kensett--are on slightly higher landscape positions and have a frequently saturated zone between depths of 0.3 and 1 meter during the wettest periods of years when the precipitation is within one standard deviation of the 30 year mean of annual precipitation
Marshan--are on landscape positions similar to those of the Tilfer soils and have a sand content of more than 70 percent in the lower half of the particle-size control section

DRAINAGE AND SATURATED HYDRAULIC CONDUCTIVITY:
Drainage class--poorly and very poorly drained--in undrained conditions, these soils are frequently saturated from the surface of the soil to a depth of 0.3 meters during the wettest periods of years when the precipitation is within one standard deviation of the 30 year mean of annual precipitation
Saturated hydraulic conductivity--1.00 to 10.00 micrometers per second
Flooding--not flooded to rarely or occasionally flooded for brief duration
Ponding--not ponded to frequently ponded for brief to long duration

USE AND VEGETATION:
Where drained, these areas are cultivated. The principal crops are corn, oats, and soybeans. Where not drained, these areas are pastured. The native vegetation is a big bluestem, western wheatgrass, sedges, blue grama and other species of the tall grass prairie that are tolerant of excessive wetness.

DISTRIBUTION AND EXTENT:
Physiographic Division--Interior Plains
Physiographic Province--Central Lowland
Physiographic Sections--Western lake section and Dissected till plains
MLRAs--Central Iowa and Minnesota Till Prairies (103) and Eastern Iowa and Minnesota Till Prairies (104)
LRR M; north central Iowa and south central Minnesota
Extent--small

MLRA OFFICE RESPONSIBLE: St. Paul, Minnesota; MLRA SSO 10-11 (Waverly, Iowa)

SERIES ESTABLISHED: Worth County, Iowa, 1972.

REMARKS:
Particle-size control section--the zone from a depth of 25 to 89 centimeters;
series control section--the zone from the surface of the soil to a depth of 89 centimeters.

Diagnostic horizons and features recognized in this pedon include:
mollic epipedon--the zone from the surface to a depth of 48 centimeters (Ap and A horizons);
cambic horizon--the zone from a depth of 48 to 69 centimeters (Bg horizon);
aquic moisture regime.

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

Taxonomy version--Keys to Soil Taxonomy, tenth edition, 2006.