LOCATION BROCKTON MAEstablished Series
TAXONOMIC CLASS: Sandy, mixed, mesic Typic Humaquepts
TYPICAL PEDON: Brockton sandy loam - forested, in an extremely stony area. (Colors are for moist soil unless otherwise noted.)
Oe--0 to 3 inches; very dark brown (10YR 2/2) hemic material. (0 to 6 inches thick)
A--3 to 14 inches; black (10YR 2/1) sandy loam, dark grayish brown (10YR 4/2) dry; moderate medium granular structure; very friable; many medium and fine roots; 4 percent gravel and 10 percent stones; common medium prominent red (2.5YR 5/6) masses of iron accumulation; extremely acid; abrupt wavy boundary. (10 to 14 inches thick)
Cg--14 to 20 inches; gray (5Y 6/1) gravelly loamy sand; massive; friable; common roots; 20 percent gravel and cobbles, and 1 percent stones; common medium prominent strong brown (7.5YR 5/8) masses of iron accumulation; very strongly acid; clear irregular boundary. (4 to 12 inches thick)
Cd--20 to 65 inches; gray (5Y 6/1) gravelly loamy sand; weak very coarse prisms; very firm; friable material 1 1/2 to 1/2 inches thick coats prisms; 20 percent gravel and cobbles, and 1 percent stones; many medium and coarse prominent yellowish brown (10YR 5/6) masses of iron accumulation; very strongly acid.
TYPE LOCATION: Plymouth County, Massachusetts; Town of Norwell, 1 mile east of Norwell Village, 1100 feet northwest of the intersection of Rt. 123 and Parker Street, 50 feet north of Parker Street. Lat. 42 degrees 09 minutes 54 seconds N. and long. 70 degrees 46 minutes 28 minutes W., NAD 27.
RANGE IN CHARACTERISTICS: Depth to the dense till ranges from 14 to 24 inches. The A horizon contains 5 to 25 percent gravel, 5 to 15 percent cobbles, and 0 to 25 percent stones. The C horizon has 5 to 25 percent gravel, 5 to 10 percent cobbles, and 0 to 15 percent stones. Reaction of the soil ranges from extremely acid through moderately acid.
The A horizon hue of 10YR, value of 2, and chroma of 1 or 2, or the horizon is neutral. Dry color values are less than 6. Texture of the fine-earth fraction is loam, very fine sandy loam, fine sandy loam, sandy loam, loamy very fine sand, loamy fine sand, or loamy sand, or their mucky analogues. Structure is granular or subangular blocky or the horizon is structureless. Consistence is very friable or loose.
The Cg horizon has hue of 10YR to 5GY, value of 4 to 7, and chroma of 1 or 2, or the horizon is neutral. Redox concentrations are common or many. Texture of the fine-earth fraction is loamy sand or loamy coarse sand. Consistence is friable, very friable, or loose.
The Cd horizon has a color range the same as the Cg horizon. Texture of the fine-earth fraction is loamy sand or loamy coarse sand above a depth of 40 inches, and sandy loam, loamy fine sand, loamy sand or loamy coarse sand below a depth of 40 inches. Consistence is firm or very firm.
COMPETING SERIES: Newton is the only other series presently in the same family. Newton soils are from outside of Region R. They formed in sandy outwash material and do not have dense substrata.
GEOGRAPHIC SETTING: Brockton soils are in depressions, on lower slopes and in drainageways on upland. Slope ranges from 0 to 3 percent. The soils formed in acid, sandy glacial till of Wisconsin age mainly from granite and gneiss. The climate is humid temperate. The mean annual temperature is 45 to 50 degrees F, and the mean annual precipitation is about 42 inches.
GEOGRAPHICALLY ASSOCIATED SOILS: Brockton soils are the very poorly drained member of a drainage sequence which includes the excessively drained Gloucester, the well drained Essex, the moderately well drained Scituate, and the poorly drained Norwell soils. The Hinckley, Windsor, Merrimac, Sudbury, and Deerfield are nearby soils formed in outwash and are all better drained than Brockton soils.
DRAINAGE AND PERMEABILITY: Very poorly drained. Runoff is very slow or ponded and internal drainage is very slow to none. Permeability is moderately rapid in the solum, and slow in the dense substratum.
USE AND VEGETATION: Mostly forested or idle. A few areas are cleared and drained and are used mostly for growing hay or pasture. Alders, sedges, rushes, and cattails are common in idle areas. The common forest trees are red maple, elm, hemlock, tamarack, spruce, balsam fir, and some white pine.
DISTRIBUTION AND EXTENT: Plymouth County, Massachusetts. (MLRAs 144A and 149B) The soils of this series are of moderate extent.
MLRA OFFICE RESPONSIBLE: Amherst, Massachusetts.
SERIES ESTABLISHED: Plymouth County, Massachusetts, 1965.
REMARKS: Diagnostic horizons and features recognized in this pedon are:
a. Umbric epipedon - the zone from the mineral soil surface to a depth of 14 inches (A horizon).
b. Sandy particle-size - the particle-size control section is dominantly sandy but has less than 50 percent very fine sand and less than 35 percent rock fragments.
c. Aquic conditions - as evidenced by an umbric epipedon directly underlain by a horizon with matrix chroma of 1 (Cg horizon).