LOCATION COSAD                   NY+MI WI

Established Series


The Cosad series consists of very deep, somewhat poorly drained soils formed in sandy deposits that overlie clayey lacustrine sediments. They are nearly level soils on lake plains. Slope ranges from 0 to 8 percent. Mean annual temperature is 48 degrees F. and mean annual precipitation is 40 inches.

TAXONOMIC CLASS: Sandy over clayey, mixed, superactive, nonacid, mesic Aquic Udorthents

TYPICAL PEDON: Cosad loamy fine sand, on a 1 percent slope in a cultivated field. (Colors are for moist soil unless otherwise noted.)

Ap -- 0 to 9 inches; very dark brown (10YR 2/2) loamy fine sand, grayish brown (10YR 5/2) dry; weak medium and coarse granular structure; very friable; many roots; moderately acid; abrupt wavy boundary. (6 to 12 inches thick.)

Bw1 -- 9 to 21 inches; pale brown (10YR 6/3) loamy fine sand; very weak medium and thick platy structure; very friable; few roots; common coarse distinct yellowish brown (10YR 5/6) soft masses of iron accumulation, and fine and medium faint light gray (10YR 7/2) and very pale brown (10YR 7/3) areas of iron depletion; slightly acid; clear wavy boundary.

Bw2 -- 21 to 30 inches; brown (7.5YR 5/4) loamy fine sand; very weak very thick platy structure; very friable; few roots; common fine and medium distinct strong brown (7.5YR 5/6) soft masses of iron accumulation; neutral; abrupt wavy boundary. (Combined thickness of the Bw horizons is 9 to 34 inches.)

2C -- 30 to 72 inches; reddish brown (5YR 4/3) silty clay; moderate very thick plate-like divisions with horizontal faces along depositional varves; faces of plates coated with light gray (5YR 7/1) silt; very firm, sticky; few roots; few fine pores; common medium prominent strong brown (7.5YR 5/6) soft masses of iron accumulation, and distinct gray (5Y 5/1) areas of iron depletion; moderately alkaline, strongly effervescent.

TYPE LOCATION: Seneca County, New York; Town of Waterloo. One hundred feet north of Steele Road and 100 feet west of Maney Road in wooded area that had been cleared and cultivated at one time. Geneva North, NY topographic quadrangle; Latitude 42 degrees, 55 minutes, 6 seconds N. and Longitude 76 degrees, 55 minutes, 50 seconds W., NAD 1927.

RANGE IN CHARACTERISTICS: The thickness of the solum ranges from 18 to 40 inches and usually corresponds to the thickness of the sandy upper deposit. Depth to bedrock is greater than 60 inches. The soil contains few or no rock fragments. Soil reaction ranges from strongly acid through slightly acid in the A horizon, strongly acid through neutral in the upper part of the B horizon, moderately acid through slightly alkaline in the lower part of the B horizon, and from neutral through moderately alkaline in the 2C horizon which is usually calcareous.

The Ap or A horizons have hue of 7.5YR through 2.5Y, value of 2 or 3, 5 or 6 dry, and chroma of 1 or 2, or they are neutral in color. Texture is fine sandy loam, loamy fine sand, loamy sand or sand. They have weak or moderate granular structure and very friable or friable consistence.

The B horizon has hue of 5YR through 2.5Y, value of 4 through 6, and chroma of 2 through 4. It has few to common redoximorphic concentrations and depletions. Depletions are chroma 2 or less above a depth of 18 inches. Texture is loamy fine sand to sand. The B horizon is structureless has weak, very fine through coarse subangular blocky or medium through very thick platy structure.

Some pedons have a 2BC horizon with colors similar to the 2C horizon. Texture is clay loam, silty clay loam, silty clay, or clay. It is massive or has weak coarse or medium prismatic structure.

The 2C horizon has hue of 2.5YR through 5GY, value of 3 through 6, and chroma of 1 through 4. It is silty clay loam, silty clay or clay. The 2C horizon is massive, or has weak or moderate medium through very thick plate-like divisions as depositional varves. Below depths of 40 inches thin lamina of silt and very fine sand are common.

COMPETING SERIES: The Claverack series is the only soil in the same family. Claverack soils are better drained and lack mottles with chroma of 2 or less above a depth of 18 inches.

The Cheektowaga, Junius, Stafford, Swanton, and Wareham series are similar soils in related families. Junius, Stafford, and Wareham soils lack contrasting clayey textures within depths of 20 to 40 inches. Cheektowaga soils have mollic epipedons. The Swanton soils have coarse-loamy over clayey particle size control sections.

GEOGRAPHIC SETTING: The Cosad soils are in nearly level low-lying or slight depressional areas of lake plains. These soils developed in sandy lake or deltaic sediments that overlie clayey lacustrine sediments. Slope ranges from 0 to 8 percent. The climate is humid and cool temperate. Mean annual temperature ranges from 45 degrees to 52 degrees F., mean annual precipitation ranges from 26 to 50 inches, and the frost-free season ranges from 120 to 180 days.

GEOGRAPHICALLY ASSOCIATED SOILS: The Cosad soils are in a drainage sequence with the moderately well drained Claverack soils and the poorly drained and very poorly drained Cheektowaga soils. Other close associates are the Elnora, Galen, Lamson, Madalin, Minoa, and Rhinebeck soils. Elnora, Galen, Lamson, and Minoa lack the clayey substrata. In addition, Elnora and Galen are on better drained landscapes. Madalin and Rhinebeck soils formed in clayey lacustrine sediments like the substratum in Cosad but lack the sandy textures in the solum.

DRAINAGE AND SATURATED HYDRAULIC CONDUCTIVITY: Somewhat poorly drained. The potential for surface runoff is negligible, high, or very high. Saturated hydraulic conductivity of the mineral surface layer and the sandy mantle is high to very high, and the fine textured lower subsoil or substratum is low to moderately high.

USE AND VEGETATION: Most areas have been cleared, however, many areas are idle and are reverting to shrubs, grasses, sedges, and weeds. Locally, drained areas are used intensively to grow vegetable crops, or silage corn and hay. Native vegetation is red maple, elm, and similar wetness-tolerant species.

DISTRIBUTION AND EXTENT: Erie and Ontario Plains, and Champlain, Mohawk, and Hudson Valleys of New York, and Wisconsin and Michigan; MLRA's 101, 142, 144A, and 95A. The series is moderately extensive.


SERIES ESTABLISHED: Seneca County, New York, 1966.

REMARKS: In some places, where the sandy mantle is of minimal thickness, cambic horizons have developed in the upper part of the clayey material. Such pedons provisionally classify as sandy over clayey, mixed, mesic Aquic Eutrochrepts and have been correlated as taxadjunts of the Cosad series.

Diagnostic horizons and other features recognized in the typical pedon:
1. Ochric epipedon - the zone from the surface to a depth of 9 inches. (Ap horizon)
2. Aquic subgroup - saturated with water with in 60 inches of the soil surface as evidenced by low chroma mottles in the subsoil and substratum. (Bw and 2C horizons)
3. Superactive CEC class - S85NY031-01
4. Non-cambic pedogenic horizon - the zone from 9 to 30 inches (Bw horizons).

National Cooperative Soil Survey