LOCATION KENYON IA+MN
Established Series
Rev. FFR-LDC-AAC
08/2013
KENYON SERIES
The Kenyon 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 880 millimeters.
TAXONOMIC CLASS: Fine-loamy, mixed, superactive, mesic Typic Hapludolls
TYPICAL PEDON: Kenyon loam, on a convex, south-facing ridge top with a slope of 3 percent, in a cultivated field. (Colors are for moist soil unless otherwise stated.)
Ap--0 to 23 centimeters; black (10YR 2/1) loam, very dark gray (10YR 3/1) dry; weak fine granular structure; friable; common fine roots; moderately acid; clear smooth boundary.
A--23 to 36 centimeters; very dark brown (10YR 2/2) loam, dark gray (10YR 4/1) dry; weak fine subangular blocky structure; friable; common fine roots; moderately acid; clear smooth boundary. (Combined thickness of the A horizon is 25 to 34 centimeters.)
AB--36 to 48 centimeters; very dark grayish brown (10YR 3/2) loam, dark grayish brown (10YR 4/2) dry; weak fine subangular blocky structure; friable; common very fine roots; strongly acid; clear smooth boundary. (0 to 15 centimeters thick)
2Bw1--48 to 104 centimeters; yellowish brown (10YR 5/6) loam; weak fine subangular blocky structure; friable; common very fine roots; about 2 percent mixed rock fragments; strongly acid; gradual smooth boundary.
2Bw2--104 to 140 centimeters; yellowish brown (10YR 5/4) loam; weak fine subangular blocky structure; firm; about 2 percent mixed rock fragments; strongly acid; gradual smooth boundary. (Combined thickness of the 2Bw horizon is 50 to 115 centimeters.)
2BC1--140 to 180 centimeters; yellowish brown (10YR 5/6) loam; weak medium subangular blocky structure; firm; common medium distinct brownish yellow (10YR 6/8) redoximorphic concentrations; common medium prominent gray (10YR 6/1) redoximorphic depletions; about 2 percent mixed rock fragments; slightly acid; gradual smooth boundary.
2BC2--180 to 200 centimeters; yellowish brown (10YR 5/6) loam; weak very coarse subangular blocky structure dissected by few oblique fractures; firm; common medium distinct brownish yellow (10YR 6/8) redoximorphic concentrations; common medium prominent gray (10YR 6/1) redoximorphic depletions; about 2 percent mixed rock fragments; neutral.
TYPE LOCATION: Major Land Resource Area (MLRA) 104-Eastern Iowa and Minnesota Till Prairies, Bremer County, Iowa subset; located about 960 feet north and 1,710 feet east of southwest corner of section 16, T. 93 N., R. 11 W.; USGS Sumner SW topographic quadrangle; lat. 42 degrees 51 minutes 52.4 seconds N. and long. 92 degrees 9 minutes 15.2 seconds W., NAD83.
RANGE IN CHARACTERISTICS:
Thickness of mollic epipedon--25 to 49 centimeters
Depth to till--30 to 75 centimeters
Depth to carbonates--greater than 114 centimeters
Content of clay in the particle-size control section (weighted average)--20 to 30 percent
Content of sand in the particle-size control section (weighted average)--20 to 50 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
Chroma--1 or 2
Texture--loam or silt loam
Clay content--14 to 27 percent
Sand content--14 to 52 percent
Rock fragment content--1 to 10 percent
Reaction--strongly acid to neutral (5.1 to 7.3)
AB or BA horizon (when present):
Hue--10YR
Value--3 or 4
Chroma--2 or 3
Texture--loam, silt loam, or sandy clay loam
Clay content--20 to 27 percent
Sand content--20 to 40 percent
Rock fragment content--1 to 10 percent
Moist bulk density - 1.4 to 1.6 gm/cc
Reaction--strongly acid to neutral (5.1 to 7.3)
Bw horizon (when present):
Hue--10YR or 2.5Y
Value--4 or 5
Chroma--2 to 6
Texture--loam, silt loam, clay loam, or sandy clay loam
Clay content--20 to 30 percent
Sand content--20 to 53 percent
Moist bulk density - 1.4 to 1.6 gm/cc
Rock fragment content--1 to 10 percent
Reaction--strongly acid to neutral (5.1 to 7.3)
2Bw horizon:
Hue--10YR or 2.5Y
Value--4 or 5
Chroma--2 to 6
Texture--loam, clay loam, or sandy clay loam
Clay content--20 to 30 percent
Sand content--24 to 58 percent
Rock fragment content--2 to 14 percent
Moist bulk density - 1.65 to 1.85 gm/cc
Calcium carbonate equivalent - 0 to 10 percent
Reaction--strongly acid to neutral (5.1 to 7.3)
2BC or 2C horizon (when present):
Hue--7.5YR to 5Y
Value--4 to 8
Chroma--1 to 8
Texture--loam
Clay content--18 to 27 percent, mean of 24 percent
Sand content--36 to 50 percent, mean of 44 percent
Rock fragment content--2 to 14 percent
Moist bulk density--1.75 to 1.9 gm/cc
Calcium carbonate equivalent- - 0 to 10 percent
Reaction--slightly acid to moderately alkaline (6.1 to 8.4)
COMPETING SERIES: These are the
Arbor,
Aredale,
Bode,
Clarion,
Cresken,
Everly,
Farrar,
Frontenac,
Garmore,
Germantown,
Limecreek,
Liscomb,
Moland,
Neeper,
Ocheyedan,
Omsrud,
Ostrander, and
Rossfield series.
Arbor--are in areas that have a mean annual air temperature range of 9 to 13 degrees C and have a mollic epipedon 41 to 61 centimeters thick
Aredale--do not have a frequently saturated zone within a depth of 1.8 meters during the wettest period of years when precipitation is within one standard deviation of the 30 year mean of annual precipitation
Bode--have an average clay content of 28 to 35 percent in the particle-size control section
Clarion--have a moist bulk density of less than 1.75 gm/cc in the lower third of the series control section
Cresken--have an average clay content of 28 to 33 percent in the particle-size control section
Everly--have carbonates within a depth of 91 centimeters
Farrar--do not have a frequently saturated zone within a depth of 1.8 meters during the wettest period of years when precipitation is within one standard deviation of the 30 year mean of annual precipitation
Frontenac--have a rock fragment content of 35 to 70 percent in the lower half of the series control section
Germantown--have a lithic contact with quartzite bedrock within a depth of 100 centimeters
Limecreek--have carbonates within a depth of 100 centimeters
Liscomb--do not have a frequently saturated zone within a depth of 1.8 meters during the wettest period of years when precipitation is within one standard deviation of the 30 year mean of annual precipitation
Moland--do not have a frequently saturated zone within a depth of 1.8 meters during the wettest period of years when precipitation is within one standard deviation of the 30 year mean of annual precipitation
Neeper--are in areas that have a mean annual air temperature range of 11 to 14 degrees C and have a rock fragment content of less than 2 percent in the lower third of the series control section
Ocheyedan--do not have rock fragments in the series control section
Omsrud--do not have a frequently saturated zone within a depth of 1.8 meters during the wettest period of years when precipitation is within one standard deviation of the 30 year mean of annual precipitation
Ostrander--do not have a frequently saturated zone within a depth of 1.8 meters during the wettest period of years when precipitation is within one standard deviation of the 30 year mean of annual precipitation
Rossfield--do not have a frequently saturated zone within a depth of 1.8 meters during the wettest period of years when precipitation is within one standard deviation of the 30 year mean of annual precipitation and have a rock fragment content of 10 to 40 percent in the lower half of the series control section
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--186 to 433 meters above sea level
Mean annual air temperature--6.4 to 10 degrees C
Mean annual precipitation--813 to 940 millimeters
Frost-free period--161 to 273 days
GEOGRAPHICALLY ASSOCIATED SOILS: Members of the typical catena include
Clyde,
Floyd,
Marquis,
Ostrander,
Readlyn, and
Tripoli soils.
Clyde-- are at lower landscape positions on concave toe slopes and in drainageways and are frequently saturated at the soil surface during the wettest periods in years when precipitation is within one standard deviation of the 30 year mean of annual precipitation
Floyd-- are at lower landscape positions on concave foot slopes and are frequently saturated at a depth of 0.4 meter during the wettest periods of years when precipitation is within one standard deviation of the 30 year mean of annual precipitation
Marquis--are at higher landscape positions on wide convex ridges and side slopes and are frequently saturated at a depth of 0.75 meter during the wettest periods of years when precipitation is within one standard deviation of the 30 year mean of annual precipitation
Ostrander--are on higher landscape positions on shoulders and narrow summits and do not have a frequently saturated within a depth of 1.8 meters during the wettest period of years when precipitation is within one standard deviation of the 30 year mean of annual precipitation
Readlyn--are at higher landscape positions on slightly convex interfluves and are frequently saturated at a depth of 0.4 meter during the wettest periods of years when precipitation is within one standard deviation of the 30 year mean of annual precipitation
Tripoli--are at lower landscape positions in flat to concave heads of drainageways and are frequently saturated at the soil surface during the wettest periods of years when precipitation is within one standard deviation of the 30 year mean of annual precipitation
DRAINAGE AND SATURATED HYDRAULIC CONDUCTIVITY:
Drainage class--moderately well drained--a frequently saturated zone occurs between depths of 1.0 and 1.8 meters during the wettest period of years when precipitation is within one standard deviation of the 30 year mean of annual precipitation, this saturation is considered both perched and apparent based on the season and intensity of rainfall during a given period of time
Saturated hydraulic conductivity--1.00 to 10.00 micrometers per second in the silty or loamy sediments and 0.01 to 1.00 micrometers per second in the till
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, and other grasses of the tall grass prairie.
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 southeastern Minnesota
Extent--large
MLRA SOIL SURVEY REGIONAL OFFICE (MO) RESPONSIBLE: Indianapolis, Indiana
SERIES ESTABLISHED: Fillmore County, Minnesota, 1955
REMARKS:
Particle-size control section--the zone from a depth of 25 to 100 centimeters (A, AB, and 2Bw1 horizons);
series control section--the zone from the surface to a depth of 150 centimeters (Ap, A, AB, 2Bw1, 2Bw2, and 2BC1 horizons).
Diagnostic horizons and features recognized in this pedon include:
mollic epipedon--the zone from the surface to a depth of 48 centimeters (Ap, A, and AB horizons);
cambic horizon--the zone from a depth of 48 to 200 centimeters (2Bw1, 2Bw2, 2BC1, and 2BC2 horizons).
Range in Characteristics were edited based on available lab data during the Kenyon Soil Data Join Recorrelation Projects FY 2013.
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.
Cation-exchange activity class is inferred from lab data from similar soils in the surrounding area. Some NSSL data supports active cation-exchange activity class.
Taxonomy version--Keys to Soil Taxonomy, eleventh edition, 2010.
The MLRA 104 Steering Committee approved property edits to this series in February 2004.
In parts of MLRAs 104 and 108, based on the definitions in Chapter 3 of the Soil Survey Manual, the drainage class of this soil would be well drained. Drainage class is a state interpretation.
The Kenyon soils are in the "Iowan Area," on an eroded landscape of Kansan and/or Nebraskan tills (Ruhe, Dietz, Fenton, and Hall; Report of Investigations, Iowa Geological Survey; 1968).
ADDITIONAL DATA:
Laboratory data--National Soil Survey Laboratory, Lincoln, Nebraska-many pedons (http://ssldata.sc.egov.usda.gov/).
Laboratory data--Soil Survey Investigations Report No. 3; Soil No. S60 Iowa-9-1 (1-11).
National Cooperative Soil Survey
U.S.A.