LOCATION TOPAZMILL          MO 
Established Series
DFF/SVV/JDP/RLT
03/2004

TOPAZMILL SERIES


The Topazmill series consists of very deep, well drained soils on foot slopes and hill sides of uplands. They formed in loamy slope alluvium and colluvium derived from sandstone. Slopes range from 3 to 35 percent. Mean annual temperature is about 56 degrees F., and mean annual precipitation is about 42 inches.

TAXONOMIC CLASS: Fine-loamy, siliceous, semiactive, mesic Typic Paleudults

TYPICAL PEDON: Topazmill fine sandy loam, 8 to 15 percent slopes, in a fescue pasture at an elevation of 670 feet. (Colors are for moist soil unless otherwise stated.)

Ap--0 to 4 inches; brown (10YR 4/3) fine sandy loam, pale brown (10YR 6/3) dry; weak fine granular structure; very friable; many fine roots throughout; many very fine irregular pores; neutral (pH 6.9); clear smooth boundary. (4 to 10 inches thick)

BA--4 to 8 inches; yellowish brown (10YR 5/6) fine sandy loam; weak fine subangular blocky structure; very friable; common fine roots throughout; many very fine irregular and tubular pores; few fine prominent discontinuous very dark brown (10YR 2/2) organic coatings on faces of peds; neutral (pH 7.0); clear smooth boundary. (0 to 8 inches thick)

Bt1--8 to 17 inches; strong brown (7.5YR 4/6) fine sandy loam; weak fine subangular blocky structure; friable; few fine roots throughout; common very fine tubular pores; few fine distinct discontinuous yellowish red (5YR 5/6) clay films on faces of peds; few fine prominent discontinuous pale brown (10YR 6/3) clay depletions on faces of peds; strongly acid (pH 5.3); gradual smooth boundary.

Bt2--17 to 26 inches; strong brown (7.5YR 5/6) fine sandy loam; weak medium subangular blocky structure; friable; many fine tubular pores; common fine prominent discontinuous yellowish red (5YR 5/6) and common medium prominent red (2.5YR 4/6) clay films on faces of peds; few fine prominent discontinuous pale brown (10YR 6/3) clay depletions on faces of peds; very strongly acid (pH 5.0); clear smooth boundary.

2Bt3--26 to 37 inches; strong brown (7.5YR 5/6) sandy clay loam; moderate medium subangular blocky structure; firm; many fine tubular pores; many coarse prominent discontinuous dark red (2.5YR 3/6) and common medium prominent yellowish brown (10YR 5/4) clay films on faces of peds; few fine prominent discontinuous pale brown (10YR 6/3) clay depletions on faces of peds; very strongly acid (pH 4.9); clear smooth boundary.

2Bt4--37 to 57 inches; mixed dark yellowish brown (10YR 4/4) and strong brown (7.5YR 5/6) clay loam; moderate medium subangular blocky structure; firm; many fine tubular pores; common coarse continuous red (10R 4/6) clay films on faces of peds; many coarse pale brown (10YR 6/3) clay depletions; very strongly acid (pH 4.9); gradual smooth boundary.

2Bt5--57 to 80 inches; red (2.5YR 4/6) clay loam; weak medium subangular blocky structure; firm; many fine tubular and irregular pores; many medium prominent discontinuous strong brown (7.5YR 5/6) and common medium prominent yellowish brown (10YR 5/4) clay films on faces of peds; common medium prominent discontinuous pale brown (10YR 6/3) clay depletions on faces of peds; very strongly acid (pH 4.8); gradual smooth boundary. (combined thickness of the Bt and 2Bt horizon is 62 or more inches)

TYPE LOCATION: Ozark County, Missouri, about 8 miles north of Tecumseh, Missouri; 1,100 feet north and 1,600 feet east of the SW corner of section 3, T. 23 N., R. 12 W.; USGS Sycamore, Missouri quadrangle; UTM coordinates Easting 564980, Northing 4061160.

RANGE IN CHARACTERISTICS:
Depth to bedrock: more than 80 inches
Solum thickness: more than 80 inches
Particle size control section averages: 30 to 50 percent sand 25 to 35 percent clay

A horizon
Hue: 10YR
Value: 3 to 5
Chroma: 2 to 4
Fine earth fraction: loam, fine sandy loam, sandy loam, silt loam
Rock fragments: 0 to 15 percent
Reaction: very strongly acid to neutral

BA horizon
Hue: 7.5YR or 10YR
Value: 4 or 5
Chroma: 2 to 6
Fine earth fraction: fine sandy loam, loam, silt loam, sandy loam
Rock fragments: 0 to 15 percent
Reaction: very strongly acid to neutral

Bt horizon
Hue: 5YR to 10YR
Value: 4 to 6
Chroma: 3 to 6
Fine earth fraction: fine sandy loam, loam, sandy clay loam, clay loam, sandy loam
Rock fragments: 0 to 35 percent
Reaction: very strongly acid to neutral

2Bt horizon
Hue: 10R to 10YR
Value: 4 to 6
Chroma: 3 to 6
Fine earth fraction: fine sandy loam, loam, sandy clay loam, clay loam, sandy loam
Rock fragments: 0 to 65 percent
Reaction: extremely acid to moderately acid

COMPETING SERIES: These are the Cottonbend, Egyptgrove, Fanchon, McClung, Nolichucky, Taterhill, Trimble, and Wyrick series. Cottonbend, Fanchon, Taterhill, and Wyrick soils have more silt and less sand in the particle-size control section. Egyptgrove soils have a Btd horizon. McClung and Trimble sois do not have a lithologic discontinuity. Nolichucky soils have rounded sandstone and quartzite fragments in the series control section.

GEOGRAPHIC SETTING: Topazmill soils are on footslopes and side slopes of uplands. They formed in loamy slope alluvium and colluvium. Slopes range from 3 to 35 percent. Elevations are commonly 550 to 1,200 feet. The mean annual temperature ranges from 54 to 58 degrees F., and the mean annual precipitation ranges from 40 to 45 inches.

GEOGRAPHICALLY ASSOCIATED SOILS: These are the Bender, Coulstone, Relfe, Sandbur, Yelton, and Zanoni series. Bender and Coulstone soils are on side slopes and are loamy skeletal. Relfe soils are sandy-skeletal. Sandbur soils are coarse-loamy. Both of these soils are on floodplains. Yelton soils have a fragpan and are on similar landscape positions. Zanoni soils are coarse-loamy and are on stream terraces.

DRAINAGE AND PERMEABILITY: Well drained. Runoff is low to high. Permeability is moderate, and the saturated hydraulic conductivity is moderately high.

USE AND VEGETATION: These soils are used mainly for pasture and hay production. The native vegetation is mixed hardwoods.

DISTRIBUTION AND EXTENT: The Ozark Highland region (MLRA 116A) of southern Missouri and possibly northern Arkansas. The series is of moderate extent.

MLRA SOIL SURVEY REGIONAL OFFICE (MO) RESPONSIBLE: Morgantown, West Virginia

SERIES ESTABLISHED: Ozark County, Missouri, 2003. The name comes from a small community in the area.

REMARKS: These soils were previously included in the Lecoma and Holstein series in mapping in southern Missouri. These soils are alfisols.

Diagnostic horizons and features recognized in this pedon are:
Ochric epipedon - the zone from the surface of the soil to a depth of 8 inches (Ap and BA horizons)
Argillic horizon - the zone from 8 to 80 inches (Bt and 2Bt horizons)

ADDITIONAL DATA: These soils are mapped primarily in the Roubidoux and upper Gasconade geologic formations.

University of Missouri soil characterization laboratory reference number 94MO15329


National Cooperative Soil Survey
U.S.A.