LOCATION AMES IA+MNEstablished Series
TAXONOMIC CLASS: Fine, smectitic, mesic Typic Albaqualfs
TYPICAL PEDON: Ames silt loam, in a depression, in a wooded pasture. (Colors are for moist soil unless otherwise stated)
A--0 to 8 centimeters; very dark brown (10YR 2/2) silt loam, gray (10YR 5/1) dry; many black (10YR 2/1) coats on faces of peds; weak fine subangular blocky structure; friable; neutral; abrupt smooth boundary. (5 to 13 centimeters thick)
E1--8 to 15 centimeters; dark gray (10YR 4/1) silt loam, gray (10YR 6/1) dry; many very dark gray (10YR 3/1) coats on faces of peds; weak medium platy structure parting to weak very fine subangular blocky; friable; strongly acid; clear smooth boundary.
E2--15 to 28 centimeters; dark gray (10YR 4/1) silt loam, gray (10YR 6/1) dry; moderate medium platy structure parting to weak fine subangular blocky; friable; common medium dark concretions (Fe and Mn oxides); strongly acid; gradual smooth boundary.
E3--28 to 43 centimeters; light brownish gray (10YR 6/2) silt loam, light gray (10YR 7/1) dry; weak very coarse platy structure parting to moderate fine subangular blocky; friable; common medium dark concretions (Fe and Mn oxides); strongly acid; abrupt smooth boundary. (Combined thickness of the E horizon is 15 to 38 centimeters.)
Btg1--43 to 53 centimeters; gray (10YR 5/1) and grayish brown (10YR 5/2) clay loam; strong fine angular blocky structure; firm; common distinct dark grayish brown (10YR 4/2) clay films on faces of peds; common medium dark concretions (Fe and Mn oxides); few fine distinct yellowish brown (10YR 5/4) redoximorphic concentrations; strongly acid; gradual smooth boundary.
Btg2--53 to 74 centimeters; gray (10YR 5/1) and grayish brown (2.5Y 5/2) clay; strong medium angular blocky structure; firm; common distinct dark gray (10YR 4/1) clay films on faces of peds; common medium dark concretions (Fe and Mn oxides); few fine distinct yellowish brown (10YR 5/4) redoximorphic concentrations; strongly acid; gradual smooth boundary.
Btg3--74 to 94 centimeters; grayish brown (2.5Y 5/2) and gray (10YR 5/1) clay loam; moderate fine prismatic structure parting to strong fine angular blocky; firm; many distinct very dark gray (10YR 3/1) and dark gray (10YR 4/1) clay films on faces of peds; common medium dark concretions (Fe and Mn oxides); few medium prominent strong brown (7.5YR 5/6) redoximorphic concentrations; moderately acid; gradual smooth boundary.
Btg4--94 to 112 centimeters; gray (10YR 5/1) clay loam; moderate very fine prismatic structure parting to strong fine angular blocky; very firm; common distinct dark gray (10YR 4/1) clay films on faces of peds and along surfaces of pores; common black (N 2/0) coats along surfaces of pores; many fine dark concretions (Fe and Mn oxides); many fine prominent strong brown (7.5YR 5/6) redoximorphic concentrations; slightly acid; gradual smooth boundary.
Btg5--112 to 135 centimeters; gray (5Y 5/1) and grayish brown (2.5Y 5/2) clay loam; strong fine angular blocky structure; very firm; common distinct dark gray (10YR 4/1) clay films on faces of peds and on surfaces along pores; common distinct black (N 2/0) coats along surfaces of pores; many medium prominent strong brown (7.5YR 5/6) redoximorphic concentrations; many fine dark concretions (Fe and Mn oxides); neutral; clear smooth boundary. (Combined thickness of the Btg horizon is 71 to 102 centimeters.)
Cg--135 to 152 centimeters; olive gray (5Y 5/2) loam; massive; firm; common distinct black (N 2/0) coats on faces of peds and along surfaces of pores; many fine dark concretions (Fe and Mn oxides); many medium prominent strong brown (7.5YR 5/6) and red (2.5YR 4/8) redoximorphic concentrations; neutral.
TYPE LOCATION: Major Land Resource Area (MLRA) 103-Central Iowa and Minnesota Till Prairies; Boone County, Iowa subset; about 4 miles northwest of Boone; located about 600 feet west and 30 feet south of the northeast corner of section 36, T. 85 N., R. 27 W; USGS Fraser topographic quadrangle; lat. 42 degrees 08 minutes 15 seconds N. and long. 93 degrees 56 minutes 02 seconds W., NAD 83.
RANGE IN CHARACTERISTICS:
Depth to carbonates--91 to 152 centimeters
Clay content of the particle-size control section (weighted average)--35 to 40 percent
Sand content of the particle-size control section (weighted average)--20 to 40 percent
A horizon:
Hue--10YR
Value--2 to 4
Chroma--1 or 2
Texture--silt loam or loam
Clay content--15 to 25 percent
Sand content--20 to 40 percent
Reaction--slightly acid or neutral
In cultivated areas, the Ap horizon has value of 4 and chroma of 1 or 2
E horizon:
Hue--10YR
Value--4 to 6
Chroma--1 or 2
Texture--silt loam or loam
Clay content--12 to 20 percent
Sand content--20 to 40 percent
Reaction--very strongly acid to moderately acid
Btg horizon:
Hue--10YR, 2.5Y, or 5Y
Value--4 or 5
Chroma--1 or 2
Texture--clay loam or clay
Clay content--32 to 42 percent
Sand content--20 to 50 percent
Reaction--strongly acid to neutral
Cg horizon:
Hue--10YR, 2.5Y, or 5Y
Value--5 or 6
Chroma--1 to 3
Texture--loam or clay loam
Clay content--20 to 30 percent
Sand content--35 to 50 percent
Reaction--slightly acid to moderately alkaline
COMPETING SERIES:
These are the
Leaksville,
Pierron,
Rushville,
Watchung,
Wynoose, and
Zwingle series.
Leaksville--have a lithic contact of shale at a depth of 150 centimeters
Pierron--have an average sand content of less than 7 percent in the particle-size control section
Rushville--have an average sand content of less than 5 percent in the particle-size control section
Watchung--have gabbro rock fragments throughout the series control section
Wynoose--have an average sand content of less than 15 percent in the particle-size control section
Zwingle--have an average clay content of 50 to 60 percent in the particle-size control section
GEOGRAPHIC SETTING:
Parent material--glacial till, reworked glacial till, or till-derived sediments
Landform--flat to slightly depressed areas of small size on dissected landscapes that border stream valleys
Slope--0 to 2 percent
Elevation--244 to 427 meters above sea level
Mean annual air temperature--7 to 11 degrees C
Mean annual precipitation--760 to 870 millimeters
Frost free period--140 to 165 days
GEOGRAPHICALLY ASSOCIATED SOILS: Members of the typical catena include
Hayden,
Lester,
Le Sueur, and
Luther soils.
Hayden and Lester--are at lower landscape positions on convex side slopes and do not have frequently saturated zones within a depth of 1.8 meters in normal years
Luther--are at slightly higher landscape positions on slight convex rises and have a frequently saturated zone at a depth of 0.3 meter during the wettest periods of normal years
Le Sueur--are at slightly higher landscape positions on slight convex rises and have a frequently saturated zone at a depth of 0.45 meter during the wettest periods of normal years
DRAINAGE AND SATURATED HYDRAULIC CONDUCTIVITY:
Drainage class--poorly or very poorly drained--in undrained conditions, these soils are frequently saturated at the soil surface during April to June in normal years 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--0.10 to 1.00 micrometers per second (moderately low)
Surface runoff potential--negligible to medium
Ponding--frequently or occasionally ponded up to 0.3 meter in depth for long duration in normal years from precipitation events and snowmelt
USE AND VEGETATION:
Some areas are used for cultivated crops if artificially drained. The principal crops are corn, soybeans, small grains, and legume hay. Many areas are in pasture or trees. Native vegetation is trees and grasses tolerant to wetness.
DISTRIBUTION AND EXTENT:
Physiographic Division--Interior Plains
Physiographic Province--Central Lowland
Physiographic section--Western lake section
MLRAs--Central Iowa and Minnesota Till Prairie (103) and Wisconsin and Minnesota Sandy Outwash (91)
LRR M; north central Iowa and south central Minnesota
Extent--small
MLRA SOIL SURVEY REGIONAL OFFICE (MO) RESPONSIBLE: St. Paul, Minnesota
SERIES ESTABLISHED: Story County, Iowa, 1936.
REMARKS:
Particle-size control section--the zone from a depth of 43 to 93 centimeters;
series control section--the zone from the surface to a depth of 150 centimeters.
Diagnostic horizons and features recognized in this pedon include:
ochric epipedon--the zone from the surface to a depth of 43 centimeters(A, E1, E2, and E3 horizons);
albic horizon--the zone from 8 to 43 centimeters (E1, E2, and E3 horizons);
argillic horizon--the zone from 43 to 135 centimeters (Btg1, Btg2, Btg3, Btg4, and Btg5);
udic moisture regime.
Taxonomy version--Keys to Soil Taxonomy, tenth edition, 2006.