LOCATION TILK MOEstablished Series
TAXONOMIC CLASS: Loamy-skeletal, siliceous, active, mesic Ultic Hapludalfs
TYPICAL PEDON: Tilk very gravelly coarse sandy loam - on a floodplain with a 1 percent slope in a forested area at an elevation of 590 feet. (Colors are for moist soil unless otherwise stated; the surface texture phase is based on mixing of the A horizon to 8 inches.)
A1--0 to 2 inches; very dark grayish brown (10YR 3/2) very gravelly coarse sandy loam, pale brown (10YR 6/3) dry; moderate fine granular structure; very friable; many very fine and fine roots and few medium roots; 10 percent chert cobbles and 50 percent chert gravel; moderately acid (pH 5.6); abrupt smooth boundary.
A2--2 to 8 inches; dark brown (10YR 3/3) very gravelly loam, pale brown (10YR 6/3) dry; moderate very fine granular structure; friable; many very fine roots and common fine and medium and few coarse roots; 10 percent chert cobbles and 39 percent chert gravel; strongly acid (pH 5.1); clear smooth boundary. (Combined thickness of the A horizon is 3 to 10 inches)
E--8 to 16 inches; brown (10YR 4/3) extremely gravelly loam; weak fine subangular blocky structure parting to moderate fine granular; friable; common very fine to coarse roots; 2 percent chert stones, 15 percent chert cobbles, and 45 percent chert gravel; very strongly acid (pH 4.9); clear smooth boundary. (0 to 8 inches thick)
Bt1--16 to 24 inches; brown (7.5YR 4/4) very cobbly loam; moderate very fine subangular blocky structure; friable; common very fine and fine roots and few medium and coarse; common distinct dark yellowish brown (10YR 4/6) clay films; 2 percent chert stones, 15 percent chert cobbles, and 23 percent chert gravel; very strongly acid (pH 4.9); clear smooth boundary.
Bt2--24 to 36 inches; strong brown (7.5YR 4/6) extremely gravelly loam; moderate fine subangular blocky structure; friable; few very fine to coarse roots; few distinct dark yellowish brown (10YR 4/6) clay films; 5 percent chert stones, 20 percent chert cobbles and 48 percent chert gravel; very strongly acid (pH 4.9); gradual wavy boundary. (Combined thickness of the Bt horizon is 15 to 40 inches)
2BC--36 to 47 inches; dark yellowish brown (10YR 4/4) extremely gravelly coarse sandy loam; weak fine subangular blocky structure; friable; few fine and medium roots; many prominent dark brown (7.5YR 3/4) clay films on rock fragments; 15 percent chert stones, 5 percent chert cobbles and 50 percent chert gravel; strongly acid; gradual wavy boundary. ( 0 to 15 inches thick)
2C--47 to 70 inches; dark yellowish brown (10YR 4/4) extremely gravelly coarse sandy loam; massive; friable; few very fine roots; 10 percent chert stones, 15 percent chert cobbles, and 45 percent chert gravel; strongly acid.
TYPE LOCATION: Madison County, Missouri; 650 feet south and 2,400 feet east of the southwest corner of section 35, T. 33 N., R. 5 E.; Rhodes Mt. USGS quadrangle; latitude 37 degrees 30 minutes 31 seconds N., longitude 90 degrees 27 minutes 49 seconds W..
RANGE IN CHARACTERISTICS: The thickness of the solum is 36 to 70 inches. The particle size control section averages 35 to 65 percent rock fragments and 40 to 60 percent fine and coarser sand, but the amount varies widely in individual horizons. Depth to the top of the argillic horizon is 7 to 16 inches.
A horizon
Hue: 10YR or 7.5YR
Value: 2 to 4
Chroma: 2 to 4
Fine earth: coarse sandy loam, sandy loam, or loam
Rock fragments: 25 to 75 percent
Reaction: strongly acid to slightly acid
E, AB, or BA horizon
Hue: 10YR or 7.5YR
Value: 4
Chroma: 3 or 4
Fine earth: loam or sandy loam
Rock fragments: 35 to 65 percent
Reaction: very strongly acid to moderately acid
Bt horizons
Hue: 10YR or 7.5YR
Value: 3 to 5
Chroma: 3 to 6
Fine earth: silt loam, loam, sandy loam, fine sandy loam, or sandy clay loam
Rock fragments: 35 to 75 percent
Reaction very strongly acid to slightly acid
2Bt horizon (where present)
Hue: 10YR or 7.5YR
Value: 4 or 5
Chroma: 4 or 6
Fine earth: sandy loam, sandy clay loam
Rock fragments: 35 to 80 percent
Reaction: moderately acid to strongly acid
2BC and 2C horizons
Hue: 10YR or 7.5YR
Value: 3 or 4
Chroma: 4 or 6
Fine earth: coarse sandy loam, loam, sandy loam, loamy coarse sand
Rock fragments: 45 to 90 percent
Reaction: very strongly acid to moderately acid
COMPETING SERIES: This is the Waben series. Waben soils have less sand and more silt in the particle size control section
GEOGRAPHIC SETTING: Tilk soils are on nearly level to gently sloping floodplains, alluvial fans, and low stream terraces. They formed in loamy and sandy alluvium containing a large amount of rock fragments. Slopes range from 0 to 5 percent. Mean annual temperature is about 54 to 57 degrees F., and mean annual precipitation is about 43 inches.
GEOGRAPHICALLY ASSOCIATED SOILS: These are the Freeburg, Nolin, Possumtrot, Racoon, Relfe, and Secesh series. Freeburg soils are somewhat poorly drained, fine-silty, and are on higher terraces. Nolin soils are well drained, fine-silty, and are on lower floodplains. Possumtrot soils are well drained, coarse-loamy, and are on similar landscape positions. Racoon soils are poorly drained, are fine family, and are on higher terrace positions. Relfe soils are excessively drained, sandy-skeletal, and are on lower floodplain positions. Secesh soils are well drained, fine-loamy, and are on similar landscape positions.
DRAINAGE AND PERMEABILITY: Somewhat excessively drained. Runoff is negligible to very low. Permeability is moderately rapid. The saturated hydraulic conductivity is high. These soils are subject to rare to occasional flooding.
USE AND VEGETATION: Most areas are cleared and used for pasture. The narrow valleys remain in forest. Native vegetation was hardwood forest.
DISTRIBUTION AND EXTENT: The Ozark Highlands (MLRA 116A) region of southern Missouri. The series is of moderate extent.
MLRA SOIL SURVEY REGIONAL OFFICE (MO) RESPONSIBLE: Morgantown, West Virginia
SERIES ESTABLISHED: Madison County, Missouri, 1998.
REMARKS: Diagnostic horizons and features recognized in this pedon are: Ochric epipedon - the zone from the surface of the soil to a depth of 16 inches (A1, A2, and E horizons).
Argillic horizon - the zone from 16 to 36 inches (Bt1 and Bt2 horizons).
Ultic feature - a base saturation by sum of cations of less than 60 percent at a depth of 66 inches.
These soils were previously included with Midco and Waben soils.
ADDITIONAL DATA: Missouri University soil characterization lab number M9312316.