LOCATION ANSGAR IA+WI
Established Series
Rev. FFR-RJK-RJB
06/2015
ANSGAR SERIES
The Ansgar series consists of very deep, poorly drained soils formed in 50 to 100 centimeters of loess and the underlying loamy glacial till or till-derived sediments. These soils are on interfluves and head slopes of broad, shallow drainageways on dissected till plains. Slope ranges from 0 to 3 percent. Mean annual air temperature is about 8 degrees C. Mean annual precipitation is about 848 millimeters.
TAXONOMIC CLASS: Fine-silty, mixed, superactive, mesic Mollic Endoaqualfs
TYPICAL PEDON: Ansgar silt loam, on a plane slope of 1 percent, in a meadow. (Colors are for moist soil unless otherwise stated.)
Ap--0 to 20 centimeters; black (10YR 2/1) silt loam, very dark gray (10YR 3/1) dry; weak fine subangular blocky structure; friable; moderately acid; abrupt smooth boundary. (13 to 24 centimeters thick)
E--20 to 31 centimeters; grayish brown (2.5Y 5/2) silt loam; moderate medium platy structure parting to moderate very fine and fine granular; friable; common distinct dark gray (10YR 4/1) coats on faces of peds; many very fine prominent yellowish brown (10YR 5/6) redoximorphic features; moderately acid; abrupt smooth boundary. (9 to 21 centimeters thick)
Btg1--31 to 46 centimeters; grayish brown (2.5Y 5/2) silty clay loam; moderate very fine subangular blocky structure; friable; common distinct very dark gray (10YR 3/1) and dark gray (10YR 4/1) clay films on faces of peds; many fine prominent yellowish brown (10YR 5/6) and few fine prominent strong brown (7.5YR 5/6) redoximorphic concentrations; moderately acid; clear smooth boundary.
Btg2--46 to 71 centimeters; gray (10YR 5/1) silty clay loam; moderate fine subangular blocky structure; friable; common distinct very dark gray (10YR 3/1) and dark gray (10YR 4/1) clay films on faces of peds; many fine and medium prominent yellowish brown (10YR 5/6) and strong brown (7.5YR 5/6) and few fine prominent yellowish red (5YR 5/6) redoximorphic concentrations; moderately acid; clear smooth boundary. (Combined thickness of the Btg horizon is 35 to 49 centimeters.)
2Btg3--71 to 91 centimeters; mottled olive gray (5Y 5/2) and strong brown (7.5YR 5/6) loam; weak medium prismatic structure parting to weak medium subangular blocky; firm; common distinct very dark gray (10YR 3/1) and dark gray (10YR 4/1) clay films on faces of peds; gray (10YR 6/1) silt coats on peds; few black (5YR 2/1) concretions (oxides); few pebbles; moderately acid; clear smooth boundary.
2Btg4--91 to 119 centimeters; gray (10YR 6/1) and grayish brown (2.5Y 5/2) sandy clay loam; moderate medium prismatic structure parting to moderate medium subangular blocky; firm; common distinct dark gray (10YR 4/1) and very dark gray (10YR 3/1) clay films on faces of peds; common medium prominent yellowish brown (10YR 5/6) and strong brown (7.5YR 5/6) redoximorphic concentrations; few small pebbles; moderately acid; clear smooth boundary. (Combined thickness of the 2Btg horizon is 35 to 57 centimeters.)
2BC--119 to 183 centimeters; yellowish brown (10YR 5/6) and light brownish gray (2.5Y 6/2) sandy clay loam; weak medium prismatic structure; firm; few large root channels lined with very dark gray (10YR 3/1) clay films; common fine distinct strong brown (7.5YR 5/6) redoximorphic concentrations; few small pebbles; slightly acid.
TYPE LOCATION: Major Land Resource Area (MLRA) 104-Eastern Iowa and Minnesota Till Prairies; Mitchell County, Iowa subset; about 3 miles east and 1 mile south of St. Ansgar; located about 400 feet east and 2,500 feet north of the southwest corner of section 28, T. 99 N., R. 17 W.; USGS Osage topographic quadrangle; lat. 43 degrees 21 minutes 49 seconds N. and long. 92 degrees 52 minutes 07 seconds W., NAD 83.
RANGE IN CHARACTERISTICS:
Depth to glacial till--50 to 100 centimeters
Clay content of the particle-size control section (weighted average)--30 to 35 percent
Sand content of the particle-size control section (weighted average)--10 to 15 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
Texture--silt loam
Clay content--18 to 25 percent
Sand content--less than 10 percent
Reaction--moderately acid to neutral
E horizon:
Hue--10YR or 2.5Y
Value--4 or 5
Chroma--1 or 2
Texture--silt loam
Clay content--15 to 20 percent
Sand content--less than 10 percent
Reaction--strongly acid to slightly acid
Some pedons have a BE horizon
Btg horizon:
Hue--10YR or 2.5Y
Value--4 or 5
Chroma--1 or 2
Texture--silty clay loam
Clay content--30 to 35 percent
Sand content--2 to 10 percent
Reaction--strongly acid to slightly acid
2Btg horizon:
Hue--10YR, 2.5Y, or 5Y
Value--5 or 6
Chroma--1 or 2
Texture--loam, sandy clay loam, or clay loam
Clay content--20 to 30 percent
Sand content--30 to 70 percent
Rock fragment content--2 to 15 percent
Reaction-- moderately acid to neutral
2BC horizon:
Hue--10YR, 2.5Y, or 5Y
Value--5 or 6
Chroma--2 to 8
Texture--loam
Clay content--18 to 27 percent, mean of 22 percent
Sand content--35 to 50 percent, mean of 44 percent
Reaction--slightly acid to moderately alkaline
Rock fragment content--2 to 12 percent
Moist bulk density--1.75 to 1.9 gm/cc
COMPETING SERIES: These are the
Blanchester,
Coppock,
Cory,
Newberry, and
Walford series.
Blanchester--occur in areas that receive more than 1,000 millimeters of precipitation annually
Coppock,
Cory, and
Walford--contain less than 15 percent sand in the lower third of the series control section
Newberry--have an average sand content of less than 8 percent in the particle-size control section
GEOGRAPHIC SETTING:
Parent Material--50 to 100 centimeters of loess and the underlying loamy glacial till or till-derived sediments
Landform--interfluves and head slopes of broad, shallow drainageways on dissected till plains
Slope--0 to 3 percent
Elevation--244 to 411 meters above sea level
Mean annual air temperature--7 to 10 degrees C
Mean annual precipitation--795 to 930 millimeters
Frost-free period--150 to 165 days
GEOGRAPHICALLY ASSOCIATED SOILS: These are the
Dinsdale,
Franklin,
Klinger, and
Maxfield soils.
Dinsdale--are at lower landscape positions on convex side slopes and have a mollic epipedon
Franklin--are in landscape positions similar to the Ansgar soils and have a frequently saturated zone at a depth of 0.3 meters during the wettest periods of normal years
Klinger--are in landscape positions similar to the Ansgar soils and have a mollic epipedon
Maxfield--are in landscape positions similar to the Ansgar soils or are in lower landscape positions in drainageways and have a mollic epipedon
DRAINAGE AND SATURATED HYDRAULIC CONDUCTIVITY:
Drainage class--poorly drained--these soils are frequently saturated at the soil surface during the wettest portions of 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--1.00 to 10.00 micrometers per second (moderately high) in the loess and 0.01 to 1.00 micrometers per second (low or moderately low) in the underlying glacial till
Surface runoff potential--negligible to low
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, switchgrass, other prairie grasses tolerant to excess wetness, and mixed deciduous trees. See Additional Data section for native vegetative cover in Iowa.
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)
LRR M; eastern Iowa and west central Wisconsin
Extent--small
MLRA SOIL SURVEY REGIONAL OFFICE (MO) RESPONSIBLE: Indianapolis, Indiana
SERIES ESTABLISHED: Mitchell County, Iowa, 1971.
REMARKS:
Particle-size control section--the zone from a depth of 31 to 81 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 31 centimeters;
argillic horizon--the zone from 31 to 119 centimeters;
udic moisture regime.
Those pedons with a minimal amount of loess in the upper 50 centimeters of the argillic horizon are marginal to the fine-loamy textural family.
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 glacial till.
Taxonomy version--Keys to Soil Taxonomy, tenth edition, 2006.
ADDITIONAL DATA: In Iowa, the native vegetative cover is a mixed herbaceous and woody community commonly inhabited with Eastern Cottonwoods, Black Willows, Silver Maples, Green Ashes, American Sycamores, Rice Cutgrasses, Grays Sedges, Bushy Cinquefoils, Nodding Beggarticks, Swamp Docks, and Calico Asters. Source: Iowa State Office, Natural Resources Conservation Service, Des Moines, IA.
National Cooperative Soil Survey
U.S.A.