LOCATION GASCONADE          MO+IA OH 
Established Series
Rev. JCB-RLT
05/2004

GASCONADE SERIES


The Gasconade series consists of shallow and very shallow, somewhat excessively drained, moderately slowly permeable soils formed in thin clayey layers with a considerable amount of coarse fragments from residuum of the underlying limestone bedrock. These soils are on steep dissected upland landscapes and generally are isolated glade areas. Slope gradients range from 2 to 50 percent. Mean annual temperature is 55 degrees F, and mean annual precipitation is 40 inches.

TAXONOMIC CLASS: Clayey-skeletal, mixed, superactive, mesic Lithic Hapludolls

TYPICAL PEDON: Gasconade flaggy clay loam, extremely stony - on an 8 percent southwest-facing slope in a hardwood forest at an elevation of 730 feet. (Colors are for moist soil unless otherwise stated.)

A--0 to 7 inches; very dark brown (10YR 2/2) flaggy clay loam; dark grayish brown (10YR 4/2) dry; moderate fine granular structure; firm; 4 percent by volume limestone channers (2mm to 75 cm) and 16 percent by volume limestone flagstones. About 3 to 10 percent of the surface is covered with stones; neutral; clear smooth boundary. (4 to 10 inches thick)

Bw--7 to 14 inches; dark brown (7.5YR 3/2) very channery clay; moderate medium subangular blocky structure; very firm; by volume about 30 percent limestone flagstones and 30 percent chert channers; slightly alkaline; clear irregular boundary. (0 to 15 inches thick)

R--14 inches; hard limestone bedrock with weathered cracks and partings containing clayey materials in the upper part.

TYPE LOCATION: Henry County, Missouri; about 7 miles south of Tightwad; about 2,190 feet south and 240 feet east of the northwest corner, sec. 26, T. 40 N., R. 24 W.; Valhalla quadrangle, lat. 38 degrees 13 minutes 25 seconds N. and long. 93 degrees 33 minutes 33 seconds W..

RANGE IN CHARACTERISTICS:

Depth to Bedrock: 4 to 20 inches
Note: Clay content in the particle size control section is 35 to 60 percent. Reaction is slightly alkaline to slightly acid.

A horizon
Hue: 10YR
Value: 2 or 3
Chroma: 1 to 3
Fine-earth: silty clay loam, clay loam, silty clay, or clay
Rock fragments: 0 to 70 percent total; 0 to 55 percent gravel, 0 to 30 percent cobbles, channers, or flagstones, 0 to 15 percent stones

Bw horizon
Hue: 7.5YR to 2.5Y
Value: 2 to 4
Chroma: 1 to 4
Fine-earth: clay, silty clay, silty clay loam, or clay loam
Rock fragments: 30 to 80 percent total; 10 to 75 percent gravel, 0 to 35 percent cobbles, channers or flagstones, 0 to 10 percent stones

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

GEOGRAPHIC SETTING: These soils are on steep dissected landscapes and generally in isolated glade areas. Slopes are 2 to 50 percent. Gasconade soils formed in thin clayey layers with a considerable amount of rock fragments from residuum of the underlying limestone bedrock. Depth to bedrock varies greatly within a short distance. Mean annual temperature varies from 50 to 56 degrees F., and the mean annual precipitation varies from 35 to 45 inches.

GEOGRAPHICALLY ASSOCIATED SOILS: These are the Bardley, Caneyville, Clarksville, Crider, Eldon, Gatewood, Goss, Pembroke, and Peridge soils. All of these soils are more than 20 inches to a lithic contact and commonly are at higher elevations in the landscape.

DRAINAGE AND PERMEABILITY: Somewhat excessively drained. Surface runoff is very high. Permeability is moderately slow. The saturated hydraulic conductivity is moderately high in the soil material and very low below the lithic contact.

USE AND VEGETATION: Most areas are in native grasses with a sparse population of cedar and low quality oaks.

DISTRIBUTION AND EXTENT: Missouri, Iowa and Ohio. The series is of large extent.

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

SERIES ESTABLISHED: Crawford County, Missouri, 1905.

REMARKS:Diagnostic horizons and features recognized in this series are:
1) Mollic epipedon - the zone from the surface of the soil to a depth of 14 inches (A and Bw horizons)
2) Lithic contact - 14 inches.


National Cooperative Soil Survey
U.S.A.