LOCATION TRESS              MN 
Established Series
RCG-AGG
09/2006

TRESS SERIES


The Tress series consists of very deep, somewhat poorly drained soils formed in calcareous glacial till on uplands. Saturated hydraulic conductivity is moderately slow. Slopes range from 0 to 3 percent. Mean annual precipitation is about 56 centimeters (22 inches), and mean annual air temperature is about 6 degrees C (43 degrees F).

TAXONOMIC CLASS: Fine-loamy, mixed, superactive, frigid Aquic Pachic Hapludolls

TYPICAL PEDON: Tress clay loam - on a nearly level slope in a cultivated field. (Colors are for moist soil unless otherwise stated.)

Ap--0 to 25 centimeters (0 to 10 inches); black (10YR 2/1) clay loam, very dark gray (10YR 3/1) dry; moderate fine and very fine subangular blocky structure; firm; common fine roots; about 2 percent rock fragments; neutral; abrupt smooth boundary.

A--25 to 51 centimeters (10 to 20 inches); black (10YR 2/1) clay loam, very dark gray (10YR 3/1) dry; moderate fine and very fine subangular blocky structure; firm; common fine roots; about 2 percent rock fragments; neutral; clear smooth boundary. [Combined thickness of A horizon is 41 to 61 centimeters (16 to 24 inches)].

Bt--51 to 91 centimeters (20 to 36 inches); olive brown (2.5Y 4/3) clay loam; moderate fine and medium subangular blocky structure; firm; common medium prominent dark yellowish brown (10YR 4/6) redox concentrations; few fine roots; common faint very dark grayish brown (10YR 3/2) clay films on faces of peds; about 2 percent rock fragments; neutral; clear smooth boundary. [13 to 51 centimeters (5 to 20 inches thick)]

Bk--91 to 122 centimeters (36 to 48 inches); grayish brown (2.5Y 5/2) clay loam; weak medium subangular blocky structure; firm; many medium prominent dark yellowish brown (10YR 4/4) redox concentrations; common fine masses of carbonates; about 2 percent rock fragments; strongly effervescent; moderately alkaline; gradual smooth boundary. [30 to 91 centimeters (12 to 36 inches)]

BC--122 to 203 centimeters (48 to 80 inches); light olive brown (2.5Y 5/3) clay loam; moderately coarse and extremely coarse prismatic structure parting to moderate medium and coarse angular blocky; firm; common medium distinct gray (2.5Y 5/1) redox depletions and common medium distinct yellowish brown (10YR 5/4) redox concentrations; about 2 percent rock fragments; strongly effervescent; moderately alkaline.

TYPE LOCATION: Lyon County, Minnesota; 671 meters (2201 feet) west and 29 meters (95 feet) north of southeast corner of section 2, T. 110 N., R. 41 W.; USGS Amiret quadrangle; lat. 44 degrees 21 minutes 22 seconds north.; long. 95 degrees 44 minutes 37 seconds W., NAD 83.

RANGE IN CHARACTERISTICS: Depth to calcium carbonate ranges from 51 to 112 centimeters (20 to 44 inches). Thickness of the mollic epipedon ranges from 41 to 61 centimeters (16 to 24 inches). Rock fragments range from 1 to 8 percent throughout, mostly pebble in size.

The A horizon has hue of 10YR, value of 2 or 3, and chroma of 1or 2. It typically is clay loam, but the range includes loam. It is neutral or slightly acid.

The Bt horizon has hue of 10YR or 2.5Y, value of 3 to 5, and chroma of 2 or 3. It is neutral or slightly alkaline. Peds in the Bt horizon have few or common faint clay films.

The Bk horizons have hue of 2.5Y, value of 4 to 6, and chroma of 2 to 4. They are clay loam or loam. They are moderately alkaline and contain both diffuse and segregated carbonates. There are common to many redox features above a depth of 76 centimeters (30 inches).

The C horizon has hue of 2.5Y, value of 4 to 6, and chroma of 2 to 6. It is clay loam or loam. It is slightly alkaline or moderately alkaline. There are common to many redox features.

COMPETING SERIES: There are no competing series in this family.

GEOGRAPHIC SETTING: Tress soils are nearly level on uplands. Slope gradients typically range from 0 to 3 percent. The soils formed in calcareous glacial till. Mean annual air temperature ranges from 3 to 7 degrees C (38 to 45 degrees F), and the mean annual precipitation ranges from 48 to 69 centimeters (19 to 27 inches). Annual frost free days are 120 to 170. Elevation ranges from 271 to 594 meters (890 to 1950 feet) above mean sea level.

GEOGRAPHICALLY ASSOCIATED SOILS: These are the Aastad, Brensall and Parnell soils. The Aastad soils are in slightly concave head slope positions. The Brensall soils are on plane to convex, slightly higher positions. The Parnell soils are in drainways and depressions.

DRAINAGE AND SATURATED HYDRAULIC CONDUCTIVITY: Somewhat poorly drained. Surface runoff is low. Saturated hydraulic conductivity is moderately slow. The apparent seasonal high saturation is at a depth of 46 to 76 centimeters (18 to 30 inches) at some time from March to June in normal years.

USE AND VEGETATION: Most areas are cultivated. The main crops are corn and soybeans. Native vegetation is tall grass prairie.

DISTRIBUTION AND EXTENT: Southwestern Minnesota.

MLRA SOIL SURVEY REGIONAL OFFICE (MO) RESPONSIBLE: St. Paul, Minnesota

SERIES ESTABLISHED: Lincoln County, Minnesota, 2006.

REMARKS: Diagnostic horizons and features recognized in this pedon are: mollic epipedon - the zone from the surface of the soil to a depth of 51 centimeters (20 inches) (Ap, A horizons); cambic horizon - the zone 51 to 91 centimeters (20 to 36 inches) (Bt horizon); calcic horizon - the zone from 91 to 122 centimeters (36 to 48 inches) (Bk horizon).

This soil was included with Aastad soils in the past. The Bt horizon does not meet the clay increase requirements for an argillic horizon.


National Cooperative Soil Survey
U.S.A.