LOCATION OSHTEMO MI+IN OH WIEstablished Series
TAXONOMIC CLASS: Coarse-loamy, mixed, active, mesic Typic Hapludalfs
TYPICAL PEDON: Oshtemo sandy loam, on a 1 percent slope in a cultivated field at an elevation of 837 feet. (Colors are for moist soil unless otherwise stated.)
Ap--0 to 9 inches; dark grayish brown (10YR 4/2) sandy loam, light brownish gray (10YR 6/2) dry; weak coarse granular structure; very friable; slightly acid; abrupt smooth boundary. (7 to 12 inches thick)
E--9 to 14 inches; brown (10YR 5/3) sandy loam, light brownish gray (10YR 6/2) dry; weak fine subangular blocky structure; very friable; many worm and root channels filled with Ap material; about 3 percent fine gravel; moderately acid; clear wavy boundary. (0 to 12 inches thick)
Bt1--14 to 26 inches; dark reddish brown (5YR 3/4) sandy loam, brown (7.5YR 4/4) dry; weak coarse subangular blocky structure; friable; common faint clay films on faces of peds; about 8 percent gravel; strongly acid; clear wavy boundary.
Bt2--26 to 35 inches; brown (7.5YR 4/4) sandy loam; weak coarse subangular blocky structure; friable; common faint clay films on faces of peds; some clay bridging between sand grains and gravel; few dark brown (7.5YR 3/2) masses 1 to 3 inches in diameter; about 5 percent gravel; strongly acid; gradual wavy boundary. (Combined thickness of the Bt horizon is 8 to 35 inches.)
BC1--35 to 46 inches; brown (7.5YR 4/4) loamy sand; single grain; loose; many dark brown (7.5YR 3/2) spots and masses up to 2 inches in diameter; about 5 percent gravel; moderately acid; diffuse irregular boundary.
BC2--46 to 60 inches; brown (7.5YR 4/4) loamy sand; single grain; loose; dark brown (7.5YR 3/2) bands 1/8 inch thick; most sand grains have dark brown (7.5YR 3/2) coatings; moderately acid; abrupt irregular boundary. (Combined thickness of the BC horizon is 0 to 30 inches.)
C--60 to 80 inches; grayish brown (10YR 5/2) stratified sand and gravelly sand; single grain; loose; some faint carbonate coatings on lower side of some gravel; about 20 percent gravel; strongly effervescent; moderately alkaline.
TYPE LOCATION: St. Joseph County, Michigan; about 1 mile north of Centreville; 800 feet north and 880 feet east of the southwest corner of sec. 18, T. 6 S., R. 10 W.; U.S.G.S. Nottawa topographic quadrangle; lat. 41 degrees 56 minutes 34.2 seconds N. and long. 85 degrees 31 minutes 28.3 seconds W., NAD 27; UTM Zone 16, 622305 easting and 4644488 northing, NAD 83.
RANGE IN CHARACTERISTICS: Depth to the base of the argillic horizon ranges from 20 to 45 inches. Thickness of the solum ranges from 40 to 75 inches. Depth to carbonates ranges from 40 to 70 inches. Mean annual soil temperature ranges from 49 to 54 degrees F.
The Ap horizon has hue of 7.5YR or 10YR, value of 3 to 5 (6 or more dry), and chroma of 2 or 3. Texture is sandy loam, fine sandy loam, coarse sandy loam, loamy sand, or loamy fine sand, or their gravelly analogues. Rock fragment content ranges from 1 to 30 percent. Reaction ranges from strongly acid to neutral.
The E horizon has hue of 10YR, value of 5 or 6, and chroma of 3 to 6, moist or dry. Texture is loam, sandy loam, fine sandy loam, loamy sand, or loamy fine sand, or their gravelly analogues. Rock fragment content ranges from 1 to 30 percent. Reaction ranges from strongly acid to neutral.
The Bt horizon has hue of 5YR to 10YR, value of 3 to 5, and chroma of 3 to 6. Texture is sandy loam, gravelly sandy loam, sandy clay loam, gravelly coarse sandy loam, gravelly sandy clay loam, or fine sandy loam. Clay content averages 10 to 18 percent. In some pedons, the lower part of the Bt horizon is in bands 1/8 to 4 inches thick separated by sand or loamy sand. In some pedons, the lower part is coarse sandy loam or gravelly coarse sandy loam. Rock fragment content ranges from 1 to 30 percent. Reaction ranges from strongly acid to slightly acid in the upper part and from strongly acid to neutral in the lower part.
The BC horizon has hue of 5YR to 10YR, value of 3 to 5, and chroma of 2 to 6. Texture is loamy sand, sandy loam, gravelly loamy sand, or gravelly sandy loam. Rock fragment content ranges from 1 to 30 percent. Reaction ranges from strongly acid to neutral.
The C horizon has hue of 10YR, value of 4 to 6, and chroma of 2 to 6. Textures are stratified and are dominantly sand, coarse sand, loamy sand, or loamy coarse sand, or their gravelly or very gravelly analogues. Rock fragment content averages 10 to 50 percent. Reaction is slightly alkaline or moderately alkaline. Some pedons have clayey or loamy substrata below 60 inches.
COMPETING SERIES: These are the Brownsburg, Crumstown, Eleva, Hillsdale, Lapeer, and Mecan series. Brownsburg soils have a lithic contact between 40 and 60 inches. Crumstown and Hillsdale soils are not clearly differentiated from the Oshtemo soils because of overlapping properties within the 0- to 60-inch series control section and because the C horizons in these soils are not always present within the series control section. In addition, the Oshtemo series allows for a loamy substratum phase that has a high water table within 60 inches. Eleva soils have a paralithic or lithic contact between 20 and 40 inches. Lapeer soils have carbonates within a depth of 40 inches. Mecan soils have more clay and silt and are not stratified in the lower part of the series control section.
GEOGRAPHIC SETTING: Oshtemo soils formed in stratified loamy and sandy deposits that have a high content of quartz and contain variable amounts of material derived from igneous and metamorphic rocks, sandstone, limestone, and dolomite. They are on outwash plains, valley trains, moraines, and beach ridges. Slope gradients range from 0 to 55 percent. Mean annual precipitation ranges from 28 to 36 inches, mean annual temperature ranges from 47 to 52 degrees F., frost-free period ranges from 120 to 180 days, and elevation ranges from 540 to 1,000 feet.
GEOGRAPHICALLY ASSOCIATED SOILS: These are the competing Hillsdale series, and the Boyer, Brady, Bronson, Gilford, Kalamazoo, and Spinks soils. The somewhat poorly drained Brady soils, the moderately well drained Bronson soils, and the poorly drained or very poorly drained Gilford soils are in a drainage sequence with the Oshtemo soils. Boyer, Spinks, and Kalamazoo soils are associated on outwash plains and valley trains. Spinks and Hillsdale soils are closely associated with Oshtemo soils on moraines. Spinks soils have argillic horizons composed of lamellae and Kalamazoo soils contain from 18 to 35 percent clay in the argillic horizon.
DRAINAGE AND PERMEABILITY: Well drained. The potential for surface runoff is negligible to medium. Permeability is moderately rapid in the upper loamy materials and very rapid in the lower sandy materials.
USE AND VEGETATION: Most areas are cultivated. Principal crops are small grains, soybeans, corn, and hay. The remainder is in forest or permanent pasture. Native vegetation is hardwood forest of oak, hickory, and sugar maple.
DISTRIBUTION AND EXTENT: MLRAs 111, 124, 139, 91, 95B, 97, 98, and 99 in southern Michigan, northern Indiana, southeastern Wisconsin, and northern Ohio. The soils are of large extent.
MLRA OFFICE RESPONSIBLE: Indianapolis, Indiana.
SERIES ESTABLISHED: Kalamazoo County, Michigan, 1922.
REMARKS: The clayey and loamy substratum phases will need to be evaluated during MLRA update activities.
Diagnostic horizons and features recognized in this pedon are: ochric epipedon - from the surface to 14 inches (Ap and E horizons); argillic horizon - from 14 to 35 inches (Bt1 and Bt2 horizons); particle-size control section - from 14 to 34 inches (Bt1 and most of the Bt2 horizon). Udic soil moisture regime.
ADDITIONAL DATA: Transect data (T02MI-149-002) is on file in the MLRA project office in Plymouth, Indiana. Transect shows 80 percent Oshtemo soils, 10 percent Ormas soils, and 10 percent Boyer soils.