LOCATION POMME MOEstablished Series
TAXONOMIC CLASS: Fine-loamy, mixed, semiactive, mesic Typic Paleudalfs
TYPICAL PEDON: Pomme silt loam, 7 percent slope in mixed pasture at an elevation of 920 feet. (Colors are for moist soil unless otherwise stated.)
Ap--0 to 7 inches; brown (7.5YR 4/3) silt loam; pale brown (10YR 6/3) dry; moderate fine subangular blocky structure parting to moderate fine granular; friable; many fine roots; 5 percent subrounded and rounded chert gravel; moderately acid; clear smooth boundary. (5 to 8 inches thick).
Bt1--7 to 19 inches; brown (7.5YR 4/4) clay loam; moderate very fine subangular blocky structure; firm; many fine roots; common distinct clay films on faces of peds; 5 percent subrounded and rounded chert gravel; slightly acid; gradual smooth boundary. (10 to 36 inches thick).
2Bt2--19 to 57 inches; red (2.5YR 4/6) very gravelly silty clay loam; moderate fine subangular blocky structure; firm; common fine roots in the upper part and few fine roots in the lower part; many distinct clay films on faces of peds; few prominent clay depletions on faces of peds; 55 percent subrounded and rounded chert gravel; strongly acid; clear wavy boundary. (20 to 60 inches thick).
3Bt3--57 to 86 inches; yellowish red (5YR 5/8) and reddish yellow (5YR 6/8) extremely gravelly clay; moderate coarse subangular blocky structure; firm; few fine roots; common distinct clay films on faces of peds; many fine masses of iron accumulation; 2 percent sandstone cobbles and 70 percent dolomite gravel; strongly acid. (0 to 40 inches thick).
TYPE LOCATION: Polk County, Missouri; about 3,050 feet east and 5,300 feet north of the southwest corner of sec. 2, T. 34N., R. 23W.; USGS Cliquot quadrangle; latitude 37 degrees 42 minutes 48 seconds N. and longitude 93 degrees 24 minutes 57 seconds W.
RANGE IN CHARACTERISTICS:
Depth to Bedrock: greater than 60 inches
Note: Rock fragments are chert, sandstone, and dolostone.
A or Ap horizon
Hue: 7.5YR or 10YR
Value: 3 or 4
Chroma: 2 to 6
Fine-earth: loam, silt loam, or silty clay loam
Total rock fragments: 0 to 25 percent; 0 to 20 percent gravel and 0 to 5 percent cobbles
Reaction: very strongly acid to neutral
BE horizon (where present)
Hue: 10YR
Value: 4 or 5
Chroma: 4 or 5
Fine-earth: silt loam
Total rock fragments: 0-15 percent gravel
Reaction: moderately acid
Bt horizon
Hue: 5YR to 10YR
Value: 3 to 5
Chroma: 4 to 6
Fine-earth: clay loam, silt loam or silty clay loam
Total rock fragments: 0 to 35 percent; 0 to 30 percent gravel and 0 to 5 percent cobbles
Reaction: strongly acid to neutral
2Bt horizon
Hue: 10R to 7.5YR
Value: 3 to 6
Chroma: 4 to 6
Fine-earth: silt loam, loam, clay loam, or silty clay loam
Total rock fragments: 5 to 70 percent; 5 to 60 percent gravel and 0 to 25 percent cobbles
Reaction: very strongly acid to neutral
3Bt or 4Bt horizon
Hue: 2.5YR to 7.5YR
Value: 3 to 6
Chroma: 6 or 8
Fine-earth: clay, silty clay, clay loam, silty clay loam, loam, or silt loam
Total rock fragments: 20 to 75 percent; 20 to 70 percent gravel and 2 to 30 percent cobbles
Reaction: very strongly acid to neutral
COMPETING SERIES: This is the Sonora series. Series in similar families are the Britwater and Holstein series. Sonora soils do not have rock fragments in the upper part of the series control section. The Britwater and Holstein soils have an active CEC/clay ratio, and do not have a lithologic discontinuity. In addition, Holstein soils have 10 percent or less rock fragments in the lower part of the argillic horizon.
GEOGRAPHIC SETTING: These soils are on structural benches, strath terraces, and footslopes. Slopes are 1 to 20 percent. They formed in a thin mantle of loess or an admixture of loess and colluvium over colluvium or old alluvial sediments. Some pedons have clayey residuum from limestone, dolostone, or sandstone beneath the sediments below a depth of 50 inches. Mean annual temperature ranges from 54 to 58 degrees, and mean annual precipitation ranges from 40 to 46 inches.
GEOGRAPHICALLY ASSOCIATED SOILS: These are the Goss, Sonsac, Dameron, and Viraton soils. Goss and Sonsac soils are clayey-skeletal and are on steeper sideslope positions adjacent to the Pomme soils. Dameron soils have a mollic epipedon and are on flood plains below the Pomme soils. Viraton soils have a fragipan and are on footslopes and ridgetops above the Pomme soils.
DRAINAGE AND PERMEABILITY: Well drained. Runoff is low to medium. Permeability is moderate, and the saturated hydraulic conductivity is moderately high.
USE AND VEGETATION: Most areas are in pasture or hayland, although some areas are used for row crops. Native vegetation is hardwood timber dominated by oak and hickory.
DISTRIBUTION AND EXTENT: The Springfield Plain region (MLRA 116B) of southwest Missouri and the Ozark Highland region (MLRA 116A) of southcentral Missouri and northern Arkansas . The series is of large extent.
MLRA SOIL SURVEY REGIONAL OFFICE (MO) RESPONSIBLE: Morgantown, West Virginia
SERIES ESTABLISHED: Polk County, Missouri soil survey; 1995.
REMARKS: Diagnostic horizons and features recognized in this series are:
Ochric epipedon - the zone from the surface to a depth of 7 inches (Ap horizon).
Argillic horizon - the zone from 7 to 80 inches (Bt, 2Bt and 3Bt horizons).
ADDITIONAL DATA: Missouri University soil characterization laboratory data number M9016706