The following is a map unit description from the "Soil Survey of Norfolk and Suffolk Counties, Massachusetts (Peragallo, 1989)"
PtB-Pittstown silt loam, 2 to 8 percent slopes. This is a very deep, gently sloping, moderately well drained soil in flat areas or depressions of upland hills in the Boston Basin. Areas of the soil are rounded or oval in shape and range from 6 to 30 acres.
Typically, the surface layer is very dark grayish brown silt loam about 10 inches thick. The subsoil is light olive brown silt loam about 20 inches thick. In the lower part it has distinct mottles. The substratum is firm, mottled, grayish brown silt loam to a depth of 60 inches or more. In a few places the subsoil and the substratum have more clay and are sticky when wet. Fragments of flat, dark gray shale and slate 1 to 15 inches long make up 50 to 75 percent, by volume, of the coarse fragments in the soil.
Included with this soil in mapping are small, more sloping areas of Newport soils. Also included are small areas of Udorthents, loamy, where the Pittstown soil has been cut away or covered with more than 20 inches of loamy fill material. Included areas make up about 20 percent of the map unit.
Soil properties:
Permeability: Moderate in the surface layer and the subsoil and slow in the substratum.
Available water capacity: Moderate.
Soil reaction: Strongly acid or moderately acid throughout.
Depth to bedrock: More than 60 inches.
Depth to the seasonal high water table: 1.5 to 2.5 feet.
Hydrologic group: C.
Most areas of this soil are used as sites for parks or public institutions. Some areas are used as individual homesites. A few areas are used as community vegetable gardens.
This soil is well suited to cultivated crops and pasture. In some years the perched seasonal high water table delays planting in spring or harvesting in fall. Drainage is needed for best crop growth and the most efficient use of machinery. The firm, compact substratum limits the installation of effective drainage systems. Cover crops and crop rotations help to reduce runoff and to control erosion. Proper stocking rates, timely grazing, and restricted use during wet periods help to maintain desirable pasture plant species.
Potential productivity for northern red oak on this soil is moderately high. The soil is easily managed for woodland use. The high productivity of this soil justifies intensive management for either hardwoods or conifers. Plant competition at regeneration is moderate if conifers are grown. Thinning crowded stands to accepted standard stocking levels allows more vigorous growth. Shelterwood cutting, seed-tree cutting, and clearcutting can be used to establish natural regeneration or to provide suitable planting sites. Removing or controlling competing vegetation allows best growth of newly established seedlings. Pruning helps to improve the quality of white pine.
Constructing buildings without basements, above the seasonal high water table, helps to prevent the damage to the interior by the seasonal high water table. Tile drains around foundations help to lower the seasonal high water table. Landscaping designed to drain surface water away from buildings and use of sump pumps in basements also help to prevent the damage to the interior by the seasonal high water table. Constructing roads on well compacted, coarse textured base material helps to protect the pavement from potential frost action.
The seasonal high water table and permeability are the main limitations to use of the soil as sites for septic tank absorption fields. Placing distribution lines in a mound of more suitable fill material helps to overcome these limitations. Erosion is a severe hazard; consequently, a vegetative cover is needed. Hay bale dams and sediment basins also help to reduce runoff and to control erosion if the soil is exposed during construction.
This soil is well suited to lawns, landscaping, and gardens. The seasonal high water table generally limits cultivation and restricts the use of machinery to late spring and early fall.