LOCATION THORNDIKE ME+NHEstablished Series
TAXONOMIC CLASS: Loamy-skeletal, isotic, frigid Lithic Haplorthods
TYPICAL PEDON: Thorndike channery silt loam, on a 10 percent southwest-facing slope in a very stony wooded area. (Colors are for moist soil.)
Oa--0 to 3 inches; black (10YR 2/1) sapric material; moderate very fine granular structure; very friable; many very fine and fine, common medium and few coarse roots; extremely acid; abrupt wavy boundary. (0 to 3 inches thick)
E--3 to 4 inches; pinkish gray (7.5YR 6/2) channery silt loam; weak very fine granular structure; very friable; few very fine roots; 30 percent channers; extremely acid; abrupt broken boundary. (0 to 3 inches thick)
Bh--4 to 6 inches; yellowish red (5YR 4/6) channery silt loam; weak fine granular structure; very friable; common very fine, few fine and medium roots; 30 percent channers; very strongly acid; abrupt broken boundary. (0 to 4 inches thick)
Bs1--6 to 8 inches; brown (7.5YR 5/4) channery silt loam; weak fine granular structure; friable; few very fine, fine, and medium roots; 30 percent channers; very strongly acid; clear wavy boundary.
Bs2--8 to 18 inches; dark yellowish brown (10YR 4/6) very channery silt loam; weak fine granular structure; friable; few very fine and fine roots; 40 percent channers; very strongly acid; clear wavy boundary. (Combined thickness of the Bs horizon is 3 to 15 inches thick)
R--18 inches; fractured bedrock.
TYPE LOCATION: Piscataquis County, Maine; Town of Sangerville; northeast of Center Pond; USGS Sangerville topographic quadrangle; lat. 45 degrees 08 minutes 03 seconds N. and long. 69 degrees 17 minutes and 57 seconds W., NAD 27.
RANGE IN CHARACTERISTICS: Thickness of the solum ranges from 10 to 20 inches and corresponds to the depth to bedrock. Rock fragments are dominantly slate, phyllite, or shale and the weighted average ranges from 35 to 80 percent of the mineral soil by volume. Stones and boulders cover from 0 to 3 percent of the surface. The soil is silt loam or loam in the fine-earth fraction. Reaction ranges from extremely acid to moderately acid, unless limed.
The Ap horizon, where present, is 6 to 10 inches thick and has hue of 10YR, value of 3 to 5, and chroma of 2 to 6. Most undisturbed areas have thin O horizons that overlie the E horizon, but a few pedons have a 1 to 2 inch thick A horizon over the E horizon. It has weak or moderate very fine, fine or medium granular structure. Consistence is very friable or friable. The A horizon, where present, has a hue of 10YR, value of 3 or 4, and chroma of 1 to 3.
The E horizon has a hue of 7.5YR or 10YR, value of 5 to 7, and chroma of 1 or 2. It has weak or moderate very fine, fine or medium granular structure. Consistence is very friable or friable.
The Bh horizon has hue of 5YR or 7.5YR, value of 3 to 5, and chroma of 2 to 6. It has weak or moderate very fine, fine or medium granular structure. Consistence is very friable or friable.
The Bhs horizon, where present, has hue of 5YR or 7.5YR value of 3 and chroma of 2 or 3. It has weak or moderate very fine, fine or medium granular structure. Consistence is very friable or friable.
The Bs horizon has hue of 5YR to 10YR, value of 4 to 6, and chroma of 4 to 8. It has weak or moderate very fine, fine or medium granular, or subangular blocky structure. Consistence is very friable or friable.
The BC horizon, where present, has hue of 2.5Y, with value and chroma of 4 to 6. It has weak or moderate very fine, fine or medium granular, or subangular blocky structure. Consistence is very friable or friable. It ranges up to 9 inches thick.
The bedrock is generally slate, phyllite, or calcareous metasedimentary rock that is fractured in the upper part.
COMPETING SERIES: The Canaan and Killington series are members of the same family. Canaan soils range from gravelly fine sandy loam to very gravelly sandy loam throughout. Rock fragments are dominantly granite. Killington soils are derived from gneiss and schist and do not have channery rock fragments.
GEOGRAPHIC SETTING: Thorndike soils are on hills and mountains. Slope ranges from 0 to 45 percent. The soils formed in a thin mantle of glacial till derived principally from slate, phyllite, or shale. The climate is humid and cool temperate. The mean annual air temperature ranges from 38 to 45 degrees F., and the mean annual precipitation ranges from 36 to 46 inches. The frost-free season ranges from 100 to 150 days. Elevation ranges from 200 to 2500 feet above mean sea level.
GEOGRAPHICALLY ASSOCIATED SOILS: These are the Bangor, Burnham, Dixmont, Monarda, Penquis, and Plaisted soils. These soils all are deeper than 20 inches to bedrock, and they all have less than 35 percent by volume of rock fragments and are located on lower positions in the nearby landscape.
DRAINAGE AND PERMEABILITY: Somewhat excessively drained. Surface runoff is slow to rapid, depending on slope and bedrock exposure. Permeability is moderate.
USE AND VEGETATION: Mostly forest. Common tree species include red spruce, white spruce, balsam fir, sugar maple, white birch, yellow birch, eastern white pine, and some white cedar. Some areas are cleared and used for growing hay, pasture, or cultivated crops.
DISTRIBUTION AND EXTENT: Maine. (MLRA 143 and 144B) The series is of large extent.
MLRA OFFICE RESPONSIBLE: Amherst, Massachusetts
SERIES ESTABLISHED: Waldo County, Maine, 1940.
REMARKS: 1. The classification is updated from Loamy-skeletal, mixed, frigid Lithic Haplorthods to Loamy-skeletal, isotic, frigid Lithic Haplorthods. Competing series section revised accordingly, 3/2006.
Previous remarks per revision 2/2000
2. This revision reflects a change in the type location from Somerset County, ME to Piscataquis County, ME to better reflect actual field conditions. 3. In Penobscot county, Maine and Aroostook County, Maine Soil Surveys, soils mapped Thorndike include both shallow and moderately deep soils. 4. Diagnostic horizons and features recognized in this pedon are:
a. Albic horizon - the zone from 3 to 4 inches (E horizon).
b. Spodic horizon - the zone from 4 to 8 inches (Bh and Bs1 horizons). c. Lithic feature - the occurrence of bedrock at a depth of 18 inches.