LOCATION OLPE KS+MOEstablished Series
TAXONOMIC CLASS: Clayey-skeletal, smectitic, thermic Typic Paleudolls
TYPICAL PEDON: Olpe gravelly silt loam - on a 4 percent west-facing slope in rangeland. (Colors are for moist soil unless otherwise stated.)
A1--0 to 8 inches; very dark grayish brown (10YR 3/2) silt loam, dark grayish brown (10YR 4/2) dry; moderate fine granular structure; slightly hard, friable; many fine roots; few pebbles; medium acid; gradual wavy boundary.
A2--8 to 13 inches; dark brown (7.5YR 3/2) silty clay loam, brown (7.5YR 5/2) dry; moderate medium granular structure; slightly hard, friable; many fine roots; about 10 percent by volume of rounded chert gravel; medium acid; gradual smooth boundary. (Combined thickness of the A horizons is 8 to 20 inches.)
BA--13 to 19 inches; dark brown (7.5YR 3/2) very gravelly silty clay loam, brown (7.5YR 5/2) dry; moderate fine subangular blocky structure; hard, firm; common fine roots; about 50 percent by volume of rounded chert gravel; medium acid; gradual wavy boundary. (0 to 15 inches thick)
Bt1--19 to 25 inches; dark brown (7.5YR 3/4) extremely gravelly silty clay, brown (7.5YR 5/4) dry; moderate fine blocky strucutre; very hard, very firm; few fine roots; about 80 percent by volume of rounded chert gravel; medium acid; gradual smooth boundary.
Bt2--25 to 36 inches; reddish brown (5YR 4/3) extremely gravelly silty clay, light reddish brown (5YR 6/3) dry; weak fine blocky structure; very hard, very firm; few fine roots; about 80 percent by volume of rounded chert gravel; medium acid; gradual wavy boundary.
Bt3--36 to 54 inches; reddish brown (5YR 4/4) very gravelly silty clay, light reddish brown (5YR 6/4) dry; common fine faint brown (7.5YR 4/4) mottles; weak medium blocky structure; very hard, very firm; few fine roots; about 45 percent by volume of rounded chert gravel; medium acid; clear wavy boundary. (Combined thickness of the Bt horizons is 15 to 50 inches.)
2Bt--54 to 60 inches; yellowish brown (10YR 5/4) silty clay, light yellowish brown (10YR 6/4) dry; many coarse prominent reddish brown (5YR 4/4) mottles; weak medium blocky structure; extremely hard, extremely firm; strongly acid.
TYPE LOCATION: Allen County, Kansas; about 4 miles west of Humboldt; about 2500 feet south and 350 feet east of the northwest corner of sec. 11, T. 26 S., R. 17 E.
RANGE IN CHARACTERISTICS: The solum is more than 60 inches thick. The mollic epipedon ranges from 10 to 24 inches. Depth to the 2Bt horizon is more than 60 inches.
The A horizon has hue of 10YR or 7.5YR, value of 2 or 3 and 3 to 5 dry, and chroma of 1 to 3. It is silt loam, gravelly silt loam, loam, gravelly loam, silty clay loam, and gravelly silty clay loam. This horizon is strongly acid to slightly acid.
The Bt horizon has hue of 2.5YR, 5YR, or 7.5YR, value of 3 to 5 and 4 to 6 dry, and chroma of 3 to 6. The fine earth fraction is silty clay, clay, silty clay loam or clay loam; or the gravelly counterparts of these textures. Rounded chert gravel ranges from 10 to 85 percent. This horizon is medium acid to neutral. Mottles with chroma of 2 or less are in some pedons.
COMPETING SERIES: The Olpe series is the only series in this family. Competing series in other families are the Clareson, Eldorado, Florence, Nowata, and Riverton series. Clareson soils have a lithic contact within depths of 40 inches and the coarse fragments in the control section are dominantly flaggy limestone. Eldorado and Riverton soils are loamy-skeletal. In addition, Riverton soils lack a mollic epipedon. Florence soils are in a drier climate and formed in residuum weathered from cherty limestone. Nowata soils are 20 to 40 inches deep over limestone and are loamy-skeletal.
GEOGRAPHIC SETTING: Olpe soils are on high terraces or uplands. Slope gradient ranges from 1 to 15 percent. The soils formed in old gravelly and clayey alluvium with some modification of the surface with deposition of loess. The mean annual temperature varies from 57 to 62 degrees F, and the mean annual precipitation varies from 32 to 40 inches. Thornthwaites Annual P-E Index ranges from 60 to 72.
GEOGRAPHICALLY ASSOCIATED SOILS: These are the Eram, Dennis, Kenoma, Lula, and Summit soils. Eram soils are on similar topography as Olpe soils but they formed in residuum weathered from shale. Dennis, Eram, and Summit soils are on areas below Olpe soils. Kenoma, and Lula soils are on smoother areas adjacent to and slightly below Olpe soils. All these associated soils have less than 15 percent coarse fragments by volume in their control section.
DRAINAGE AND PERMEABILITY: Well drained. Runoff is medium or rapid. Permeability is slow.
USE AND VEGETATION: Most is used for rangeland. Native vegetation is tall grass prairie. Many areas have been quarried and used as a source of gravel.
DISTRIBUTION AND EXTENT: Southeast Kansas and possibly adjacent parts of Oklahoma. The series is moderately extensive.
MLRA OFFICE RESPONSIBLE: Salina, Kansas
SERIES ESTABLISHED: Butler County, Kansas, 1970.