LOCATION CABOT                   VT+MA ME NH

Established Series
Rev. SHG-ANA-RFL
04/2015

CABOT SERIES


The Cabot series consists of poorly drained soils that formed in loamy lodgment till on glaciated uplands and lowlands. They are shallow to a dense substratum and very deep to bedrock. Estimated saturated hydraulic conductivity is moderately high or high in the mineral solum and low, moderately low, or moderately high in the dense substratum. Slope ranges from 0 to 25 percent. Mean annual precipitation is about 1180 mm, and mean annual temperature is about 6 degrees C.

TAXONOMIC CLASS: Loamy, mixed, active, nonacid, frigid, shallow Typic Humaquepts

TYPICAL PEDON: Cabot silt loam, on a southeast facing 5 percent slope, in a very stony wooded area. (Colors are for moist soils unless otherwise noted.)

Oi--0 to 3 cm; peat. (O horizon thickness is 0 to 19 cm.)

A--3 to 23 cm; very dark gray (5Y 3/1) silt loam, dark grayish brown (2.5Y 4/2) dry; weak medium subangular blocky structure; friable; common fine and medium roots; 5 percent rock fragments; strongly acid (pH 5.3); abrupt wavy boundary. (0 to 23 cm thick)

Bg--23 to 36 cm; dark olive gray (5Y 3/2) silt loam; weak medium subangular blocky structure; friable; few fine roots; common fine faint dark grayish brown (2.5Y 4/2) iron depletions in the matrix; 10 percent rock fragments; strongly acid (pH 5.5); clear wavy boundary. (8 to 38 cm thick)

BCg--36 to 43 cm; dark olive gray (5Y 3/2) channery silt loam; massive; friable; many fine prominent dark yellowish brown (10YR 3/4 and 10YR 4/6) masses of iron accumulation in the matrix; 15 percent rock fragments; strongly acid (pH 5.5); clear wavy boundary. (0 to 8 cm thick)

Cdg1--43 to 56 cm; dark olive gray (5Y 3/2) channery fine sandy loam; massive; firm; many fine prominent dark yellowish brown (10YR 3/4 and 10YR 4/6) masses of iron accumulation in the matrix; 20 percent rock fragments; strongly acid (pH 5.5); gradual wavy boundary.

Cdg2--56 to 165 cm; dark gray (N 4/0) channery silt loam; massive; firm; many fine prominent dark yellowish brown (10YR 3/4 and 10YR 4/6) masses of iron accumulation in the matrix; 20 percent rock fragments; moderately acid (pH 5.6).

TYPE LOCATION: Washington County, Vermont; Town of East Montpelier; located about 2,060 meters south of the Calais town line and 90 meters east of Chapels Pond; USGS Montpelier, VT topographic quadrangle; lat. 44 degrees 18 minutes 54.31 seconds N. and long. 72 degrees 31 minutes 2.60 seconds W., NAD 83.

RANGE IN CHARACTERISTICS: The thickness of the mineral solum is less than 50 cm. Depth to bedrock is greater than 165 cm. Rock fragments range from 5 to 35 percent in the solum and 5 to 50 percent in the substratum. The rock fragments consist mainly of schist, slate, phyllite, granite, quartzite, shale, or limestone. Reaction ranges from strongly acid to neutral in the A and B horizons, and moderately acid to mildly alkaline in the C horizon. Carbonates are present in some pedons below a depth of 100 cm.

The O horizons, where present, consist of peat, mucky peat, and/or muck.

The A horizon, or Ap horizon where present, has hue of 10YR to 5Y, value of 2 to 3, and chroma of 1 or 2. It is silt loam, loam, very fine sandy loam, or fine sandy loam in the fine earth fraction. Some pedons have ABg horizons up to 18cm thick.

The Bg horizon is neutral or has hue of 10YR to 5Y, or 5GY, value of 2 to 5, and chroma of 0 to 2. It is silt loam, loam, very fine sandy loam, fine sandy loam, or sandy loam in the fine earth fraction.

The BCg horizon has hue of 10YR to 5Y, value of 3 to 5 and chroma of 1 or 2. It is silt loam, loam, very fine sandy loam, or fine sandy loam in the fine earth fraction.

The Cdg horizon is neutral or has hue of 10YR to 5Y, or 5GY, value of 2 to 5, and chroma of 0 to 2. It is silt loam, loam, very fine sandy loam, fine sandy loam, or sandy loam in the fine earth fraction. The Cdg horizon has plates of geogenic origin or is massive. It is firm to extremely firm. Some pedons have a Cd horizon with dominant chroma higher than 2.

COMPETING SERIES: There are no other series in the same family. The Brayton, Monarda, Pillsbury, and Ridgebury soils are in related families. Brayton, Monarda, Pillsbury, and Ridgebury soils have dominant chroma higher than 2 in a subhorizon of the B or BC horizon within a depth of 75 cm. Ridgebury soils also have a mesic soil temperature regime.

GEOGRAPHIC SETTING: Cabot soils are on nearly level to moderately steep slopes on hills and mountains. They are on concave backslopes and footslopes, on toeslopes, and in depressions and drainageways. Less frequently, Cabot soils occur on broad till plains. The soils formed in loamy lodgment till of Wisconsin age derived mainly from schistose rocks and impure limestone. Slope ranges from 0 to 25 percent. Tree-tip pit and mound topography is common in unplowed areas. The mean annual precipitation is 790 to 1640 mm, and the mean annual temperature is 2 to 7 degrees C. The frost free period is 70 to 135 days. Elevation ranges from about 100 to 650 meters above mean sea level.

GEOGRAPHICALLY ASSOCIATED SOILS: These are the Brayton, Buckland, Colonel, Marlow, Peacham, Peru, Sunapee, Tunbridge, and Vershire soils. Brayton soils are in positions similar to Cabot soils and have a higher dominant chroma in the B or BC horizon. Buckland and Vershire soils typically occur in areas where the underlying bedrock contains impure limestone. They are better drained and are on convex slopes above the nearby Cabot soils. Colonel, Marlow, Peru, Sunapee, and Tunbridge soils typically occur in areas where the underlying bedrock is schist, gneiss, or granite. They are better drained and are on convex slopes above the nearby Cabot soils. Peacham soils are very poorly drained and occur throughout the extent of Cabot soils.

DRAINAGE AND SATURATED HYDRAULIC CONDUCTIVITY: Poorly drained. Estimated saturated hydraulic conductivity is moderately high or high in the solum and low, moderately low, or moderately high in the dense substratum.

USE AND VEGETATION: Most areas are wooded. The common trees are red spruce, white spruce, balsam fir, tamarack, hemlock, white cedar, white pine, red maple, sugar maple, yellow birch, paper birch, and elm. Some areas have been cleared and are primarily used for hay and pasture. A few cleared areas are used for cultivated crops.

DISTRIBUTION AND EXTENT: Vermont, New Hampshire, the northern part of Massachusetts, and Maine; MLRAs 142, 143, and 144B. The series is extensive.

MLRA SOIL SURVEY REGIONAL OFFICE (MO) RESPONSIBLE: Amherst, Massachusetts.

SERIES ESTABLISHED: Essex County, Vermont, 1948.

REMARKS: The horizons and features diagnostic for the typical pedon are:
Umbric epipedon - the zone from 3 to 23 cm (A horizon).
Cambic horizon - the zone from 23 to 43 cm (Bg and BCg horizons).
Redoximorphic features - iron depletions in the zone from 23 to 36 cm (Bg horizon); chroma of 2 or less and redox concentrations in the zone from 36 to 43 cm (BCg horizon).
Densic materials - the zone from 43 to 165 cm (Cdg1 and Cdg2 horizons).

ADDITIONAL DATA: Characterization data for Cabot and similar soils is available through the National Cooperative Soil Survey Soil Characterization Database: http://ncsslabdatamart.sc.egov.usda.gov/


National Cooperative Soil Survey
U.S.A.