LOCATION DONIPHAN MO+AREstablished Series
TAXONOMIC CLASS: Very-fine, mixed, semiactive, mesic Typic Paleudults
TYPICAL PEDON: Doniphan very gravelly silt loam, on a southwest-facing slope of 6 percent under a mixed hardwood forest at an elevation of 560 feet. (Colors are for moist soil unless otherwise stated.)
A--0 to 2 inches; dark grayish brown (10YR 4/2) very gravelly silt loam, light brownish gray (10YR 6/2) dry; moderate very fine and fine granular structure; very friable; common medium and fine roots; many fine pores; many worm channels and casts; a few fine black concretions (oxides); 60 percent chert gravel; slightly acid; abrupt smooth boundary. (1 to 6 inches thick)
E--2 to 12 inches; light yellowish brown (10YR 6/4) very gravelly silt loam; many fine faint yellowish brown (10YR 5/4) mottles; weak very fine granular structure; very friable; common medium and fine roots; many fine pores; common worm channels and casts; common fine black iron and manganese concretions; 55 percent chert gravel; strongly acid; clear wavy boundary. (2 to 14 inches thick)
B/E--12 to 16 inches; yellowish red (5YR 5/8) gravelly silty clay loam (Bt); light yellowish brown (10YR 6/4) silt loam (E) comprises about 10 percent of the mass; moderate fine and very fine subangular blocky structure; friable; common fine roots; many fine pores; common worm channels and casts; few faint red clay films on faces of peds; common fine black iron and manganese concretions; 15 percent chert gravel; strongly acid; clear wavy boundary. (0 to 6 inches thick)
2Bt1--16 to 27 inches; red (2.5YR 4/6) clay; strong fine angular blocky structure; firm; common fine roots; few fine pores; few faint red (10YR 4/6) clay films on faces of peds; few worm channels; few fine prominent light yellowish brown (10YR 6/4) and strong brown (7.5YR 5/6) masses of iron accumulation; few fine dark iron and manganese concretions; few fine chert gravel; very strongly acid; clear wavy boundary. (5 to 20 inches thick)
2Bt2--27 to 41 inches; red (2.5YR 4/6) clay; strong fine angular blocky structure; firm; common fine roots; few fine pores; few faint red clay films on faces of peds; few worm channels; common fine prominent light yellowish brown (10YR 6/4) and strong brown (7.5YR 5/6) masses of iron accumulation; few fine black iron and manganese concretions; less than 5 percent chert gravel; very strongly acid; clear wavy boundary. (5 to 20 inches thick)
2Bt3--41 to 55 inches; mottled red (2.5YR 4/6) and brownish yellow (10YR 6/6) clay; moderate fine angular blocky structure; friable; common fine roots; few fine pores; few faint red clay films on faces of peds; few worm channels;common fine prominent strong brown (7.5YR 5/8) and few fine distinct light yellowish brown (10YR 6/4) masses of iron accumulation; few fine prominent light gray (10YR 7/2) iron depletions; few fine black iron and manganese concretions; few fine chert gravel; very strongly acid; abrupt wavy boundary. (7 to 20 inches thick)
2Bt4--55 to 77 inches; brownish yellow (10YR 6/6) clay; moderate fine and very fine angular blocky structure; friable; common fine roots; few fine pores; many distinct clay films on faces of peds; few worm channels; common coarse distinct red (10YR 4/6) and few fine distinct light yellowish brown (10YR 6/4) masses of iron accumulation; prominent light gray (N 7/ ) iron depletions; few fine black iron and manganese concretions; few fine chert gravel; very strongly acid.
TYPE LOCATION: Ripley County, Missouri; about 1 1/2 miles west of the town of Burr; 1240 feet south and 1400 feet east of the northwest corner, sec. 6, T. 21 N., R. 1 E; USGS Gatewood quadrangle, lat. 36 degrees 30 minutes 46 seconds N. and long. 91 degrees 0 minutes 44 seconds W.
RANGE IN CHARACTERISTICS: Content of chert fragments ranges from 25 to 75 percent by volume in the A and E horizons, from 0 to 30 percent by volume in the Bt horizon and upper part of the 2Bt horizon, and from 0 to 80 percent in lower part of the 2Bt horizon. Some pedons have stone size chert fragments on the surface. The mean annual soil temperature at 20 inches it 55 to 59 degrees F.
The A horizon has hue of 10YR, value of 2 to 4, and chroma of 1 to 3. The Ap horizon has hue of 10YR, value of 4 to 6, and chroma of 2 or 3. The E horizon has hue of 10YR, value of 4 to 6, and chroma of 3 or 4. They are the gravelly or very gravelly analogues of silt loam or loam. Reaction is very strongly acid to slightly acid.
The Bt part of the B/E horizon and upper part of the 2Bt horizons have hue of 10R to 7.5YR, value of 3 to 5, and chroma of 4 to 8. Color of the lower part of the 2Bt horizons are quite variable, and colors are mottled in most pedons. They have hue of 2.5Y to 10YR, value of 3 to 7, and chroma of 4 to 8 except for few or common gray mottles that are neutral or have chroma of 1 or 2. The upper 20 inches of the argillic horizon averages between 48 and 70 percent clay. The 2Bt horizon ranges from strongly acid to extremely acid. The Bt part of the B/E horizon is silty clay loam or gravelly silty clay loam. The upper part of the 2Bt horizon is clay or gravelly clay. The lower part is clay or the gravelly to extremely gravelly analogues of clay.
COMPETING SERIES: There are no other series in this family. Series in similar families are the Macedonia and Frederick series. Macedonia soils have less clay in the upper part of the argillic horizon and commonly fewer coarse fragments in the upper part of the solum. Frederick soils have less than 25 percent coarse fragments in the upper part of the solum.
GEOGRAPHIC SETTING: Doniphan soils are on side slopes and narrow ridgetops. Slopes typically range from 10 to 35 percent, but have an extreme range of 2 to 60 percent. The soils formed in is residuum from clayey shales and cherty dolomite or cherty limestone. Mean annual temperature ranges from 55 to 58 degrees F, and mean annual precipitation ranges from 40 to 50 inches.
GEOGRAPHICALLY ASSOCIATED SOILS: These are the competing Macedonia and the Bardley, Coulstone, Clarksville, Gasconade, Gassville, Gatewood, Hobson, Lebanon, Opequon, Poynor, Viraton, and Wilderness soils. Macedonia soils are commonly on higher ridgetops. Bardley and Gatewood soils have lithic contacts within 40 inches of the surface and occur above Doniphan in the landscape. Coulstone and Clarksville soils are loamy-skeletal and are on steep side slopes and narrow ridgetops. Gasconade and Opequon soils have lithic contacts within 20 inches of the surface and are on slopes below the Doniphan soils. Poynor soils are loamy-skeletal over clayey and are on similar slopes as Doniphan. Gassville soils are on adjacent lower side slopes and have solums less than 40 inches thick. Hobson, Lebanon, Viraton, and Widerness soils have fragipans and are on broad ridgetops.
DRAINAGE AND PERMEABILITY: Well drained. Medium to high runoff potential. Permeability is moderate.
USE AND VEGETATION: The majority of these soils are in second growth timber. Pasture and hay or grain crops are grown on some areas. Native vegetation is deciduous hardwoods.
DISTRIBUTION AND EXTENT: Ozarks region (MLRAs 116A and 116B) of southern Missouri and northern Arkansas. The series is extensive.
MLRA SOIL SURVEY REGIONAL OFFICE (MO) RESPONSIBLE: Morgantown, West Virginia
SERIES ESTABLISHED: Mark Twain National Forest in Carter, Oregon, Ripley, and Shannon Counties, Missouri, 1972.
REMARKS: Diagnostic horizons and features recognized in this series are: ochric epipedon - the zone from the surface of the soil to a depth of 12 inches (A and E horizons);
argillic horizon - the zone from approximately 12 to 77 inches or more (B/E, 2Bt1, 2Bt2, 2Bt3, and 2Bt3 horizons).
Doniphan soils were formerly mapped with the Baxter series in Missouri.