LOCATION ARBOR                   IA

Established Series
Rev. FFR-JRW-TWN
10/2012

ARBOR SERIES

The Arbor series consists of very deep, well drained soils formed in 45 to 75 centimeters of loamy local alluvium and in the underlying firm glacial till. These soils are on slightly concave to linear foot slopes adjacent to dissected uplands. Slope ranges from 5 to 20 percent. Mean annual precipitation is about 890 millimeters. Mean annual air temperature is about 10 degrees C.

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

TYPICAL PEDON: Arbor loam, on a slightly concave slope of 14 percent, in a cultivated field. (Colors are for moist soil unless otherwise stated.)

Ap--0 to 15 centimeters; very dark brown (10YR 2/2) loam, dark grayish brown (10YR 4/2) dry; weak fine and medium granular structure; friable; moderately acid; clear smooth boundary.

A1--15 to 36 centimeters; very dark brown (10YR 2/2) loam, dark grayish brown (10YR 4/2) dry; moderate fine and medium granular structure; friable; moderately acid; gradual smooth boundary.

A2--36 to 46 centimeters; very dark brown (10YR 2/2) clay loam; weak fine subangular blocky structure; friable; some mixing of brown (10YR 4/3); moderately acid; clear smooth boundary. (Combined thickness of the A horizon is 40 to 50 centimeters.)

BA--46 to 61 centimeters; brown (10YR 4/3) loam; weak fine subangular blocky structure; friable; very dark grayish brown (10YR 3/2) coats on faces of peds; moderately acid; abrupt smooth boundary. (0 to 20 centimeters thick)

2Bt1--61 to 81 centimeters; brown (10YR 4/3) loam; moderate fine subangular blocky structure; friable; faint clay films; few stones and pebbles; moderately acid; gradual smooth boundary.

2Bt2--81 to 112 centimeters; brown (10YR 4/3) loam; weak medium subangular blocky structure grading as depth increases to weak coarse subangular blocky; firm; few faint clay films; few faint grayish brown (10YR 5/2) redoximorphic depletions; common prominent strong brown (7.5YR 5/6) redoximorphic concentrations; few stones and pebbles; slightly acid; gradual smooth boundary. (Combined thickness of the 2Bt horizon is 20 to 64 centimeters.)

2BC--112 to 152 centimeters; brown (10YR 4/3) and yellowish brown (10YR 5/4) clay loam; weak very coarse subangular blocky structure; friable; common distinct grayish brown (10YR 5/2) redoximorphic depletions; common prominent strong brown (7.5YR 5/6) redoximorphic concentrations; few stones and pebbles; neutral.

TYPE LOCATION: Major Land Resource Area (MLRA) 108-Illinois and Iowa Deep Loess and Drift; Adair County, Iowa subset; about 6 miles north of Greenfield; located about 1,810 feet east and 1,300 feet south of the northwest corner of section 18, T. 76 N., R. 31 W.; USGS Rosserdale topographic quadrangle; lat 41 degrees 23 minutes 06 seconds N. and long. 94 degrees 27 minutes 53 seconds W., NAD 83.

RANGE IN CHARACTERISTICS:
Thickness of mollic epipedon--40 to 50 centimeters
Depth to carbonates--more than 125 centimeters
Depth to glacial till--45 to 75 centimeters
Content of clay in the particle-size control section (weighted average)--25 to 35 percent
Content of sand in the particle-size control section (weighted average)--25 to 45 percent

Ap and A horizon:
Hue--10YR
Value--2
Chroma--1 or 2
Texture--loam, clay loam, or silty clay loam
Clay content--25 to 35 percent
Sand content--10 to 40 percent
Rock fragment content--0 to 1 percent
Reaction--moderately acid to neutral

BA horizon (when present):
Hue--10YR
Value--4
Chroma--3
Texture--loam or clay loam
Clay content--25 to 35 percent
Sand content--20 to 40 percent
Rock fragment content--0 to 1 percent
Reaction--moderately acid to neutral

Many pedons have a thin stone line at the contact of the local alluvium and the glacial till

2Bt horizon:
Hue--10YR
Value--4 or 5
Chroma--3 to 6
Texture--loam or clay loam
Clay content--22 to 35 percent
Sand content--25 to 50 percent
Rock fragment content--2 to 10 percent
Reaction--strongly acid to slightly acid

2BC or 2C horizon:
Hue--10YR
Value--4 or 5
Chroma--3 to 6
Texture--loam or clay loam
Clay content--22 to 35 percent
Sand content--25 to 50 percent
Rock fragment content--2 to 10 percent
Reaction--neutral to moderately alkaline

COMPETING SERIES:
These are the Aredale, Bode, Clarion, Cresken, Everly, Farrar, Frontenac, Garmore, Germantown, Kenyon, Limecreek, Liscomb, Moland, Neeper, Ocheyedan, Omsrud, Ostrander, and Rossfield series
Aredale--have firm glacial till within depths of 100 to 150 centimeters
Bode--have carbonates within a depth of 125 centimeters
Clarion--have carbonates within a depth of 125 centimeters and have a rock fragment content of 1 to 10 percent throughout the series control section
Cresken--have very firm consistence and chroma of 1 or 2 in the lower two thirds of the series control section
Everly--have carbonates within a depth of 90 centimeters
Farrar--have a sand content of more than 50 percent in the upper half of the series control section and has a clay content that averages 18 to 24 percent in the particle-size control section
Frontenac--have a rock fragment content of 35 to 75 percent in the lower third of the series control section.
Garmore--have a rock fragment content of 2 to 10 percent throughout the series control section
Germantown--have a lithic contact of quartzite within a depth of 100 centimeters
Kenyon--have a rock fragment content of 1 to 10 percent in the upper third of the series control section
Limecreek--have carbonates within a depth of 100 centimeters
Liscomb--have carbonates within a depth of 125 centimeters
Moland--have a mollic epipedon 25 to 41 centimeters thick
Neeper--does not have a lithologic discontinuity and does not have rock fragments in the lower half of the series control section
Ocheyedan--have carbonates within depths of 50 and 165 centimeters and does not have rock fragments in the series control section
Omsrud--have carbonates within a depth of 125 centimeters
Ostrander--have firm glacial till within depths of 75 and 140 centimeters
Rossfield--have a rock fragment content of 10 to 40 percent within a depth of 100 centimeters

GEOGRAPHIC SETTING:
Parent material--45 to 75 centimeters of loamy local alluvium and in the underlying firm glacial till (Kansan)
Landform--slightly concave to linear foot slopes adjacent to dissected uplands
Slope--5 to 20 percent
Elevation--305 to 427 meters above sea level
Mean annual air temperature--9 to 11 degrees C
Mean annual precipitation--840 to 940 millimeters
Frost-free period--175 to 200 days

GEOGRAPHICALLY ASSOCIATED SOILS:
These are the Olmitz and Shelby soils.
Olmitz--are at lower landscape positions on the more concave portion of lower foot slopes and have a mollic epipedon 60 to 100 centimeters thick
Shelby--are at higher landscape positions on convex side slopes and have a rock fragment content of 2 to 10 percent throughout the series control section

DRAINAGE AND SATURATED HYDRAULIC CONDUCTIVITY:
Drainage class--well drained--a frequently saturated zone does not occur within a depth of 1.8 meters during the wettest periods of normal years
Saturated hydraulic conductivity--1.00 to 10.00 micrometers per second (moderately high)
Surface runoff potential--medium

USE AND VEGETATION:
Most areas are cultivated. The principal crops are corn, soybeans, small grains, and 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--Dissected till plains
MLRA--Illinois and Iowa Deep Loess and Drift (108)
LRR M; southwestern Iowa
Extent--small

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

SERIES ESTABLISHED: Adair County, Iowa, 1958.

REMARKS:
Particle-size control section--the zone from a depth of 25 to 100 centimeters;
series control section--the zone from the surface to a depth of 150 centimeters.

Diagnostic horizons and features recognized in this pedon include:
mollic epipedon--the zone from the surface to a depth of 46 centimeters (Ap, A1, and A2 horizons);
cambic horizon--the zone from a depth of 46 to 152 centimeters (BA, 2Bt1, 2Bt2, and 2BC horizons);
udic moisture regime.

The Arbor soils were formerly classified as Argiudolls based on the difference in texture of materials 1 and 2 and the presence of a few clay films.

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

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

ADDITIONAL DATA:
Laboratory data--National Soil Survey Laboratory, Lincoln, Nebraska - user pedon IDs 56IA001001 and 56IA001002 (http://ssldata.nrcs.usda.gov/).

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National Cooperative Soil Survey
U.S.A.