LOCATION BROWNSBURG PAEstablished Series
TAXONOMIC CLASS: Coarse-loamy, mixed, active, mesic Typic Hapludalfs
TYPICAL PEDON - Brownsburg silt loam, 3 to 8 percent slopes, in a cropped field on an upper side slopes of summits, at an elevation of 480 feet. (Colors are for moist soil.)
Ap--0 to 10 inches; brown to dark brown (10YR 4/3) silt loam; weak fine and medium subangular blocky structure parting to weak medium granular; friable, nonsticky and nonplastic; common fine roots throughout; common fine and medium discontinuous tubular pores; 2 percent channers of sandstone; neutral; abrupt smooth boundary. (8 to 12 inches thick.)
Bt1--10 to 18 inches; brown to dark brown (10YR 4/3) silt loam; weak fine subangular blocky structure; friable, slightly sticky and slightly plastic; common fine roots throughout; common very fine and fine discontinuous tubular pores; very few faint brown and dark brown (7.5YR 4/4) discontinuous clay films on faces of peds and in pores; fine cylindrical worm casts; 2 percent channers of sandstone; strongly acid; gradual wavy boundary
Bt2--18 to 30 inches; brown to dark brown (7.5YR 4/4) silt loam; moderate fine and medium subangular blocky structure; firm, slightly sticky and slightly plastic; few fine roots throughout; common fine discontinuous tubular pores; very few faint brown and dark brown (7.5YR 4/4) discontinuous clay films on faces of peds and in pores; 2 percent channers of sandstone; moderately acid; abrupt wavy boundary. (The combined thickness of the Bt horizons is 12 to 24 inches.)
2Btb--30 to 44 inches; dark reddish brown (2.5YR 3/4) very channery loam; moderate medium subangular blocky structure; firm, nonsticky and nonplastic; few fine discontinuous tubular pores; few fine faint brown and dark brown (7.5YR 4/4) discontinuous clay films on faces of peds and in pores; 45 percent channers of shale; moderately acid; clear wavy boundary. (10 to 16 inches thick.)
2Cr--44 to 56 inches; dark reddish brown (2.5YR 3/4) extremely channery silt loam; massive; very firm, nonsticky and nonplastic; many very fine and fine discontinuous tubular pores; very few faint dark reddish brown (2.5YR 3/4) patchy clay films on rock fragments; 80 percent channers and 10 percent pebbles of shale; slightly acid; clear smooth boundary. (8 to 12 inches thick.)
R--56 inches; extremely hard, weak red (10R 4/4) moderately weathered and fractured shale bedrock.
TYPE LOCATION: Brownsburg silt loam, 3 to 8 percent slopes, in a cropped field, in Buck County, Makefield Township, 0.6 of mile south-southwest of Brownsburg, 3300 feet southwest on Brownsburg Road from intersection of Brownsburg Road and Pennsylvania Route 32, then 880 feet east on field lane from Brownsburg Road, then 100 feet south; USGS Lambertville topographic quadrangle; Lat. 40 degrees 18 minutes 37 seconds N. and Long. 75 degrees 55 minutes 29 degrees W.
RANGE IN CHARACTERISTICS: Solum thickness ranges from 30 to 60 inches. Depth to Bedrock is 40 to 60 inches. Depth to redox depletions or iron concentrations is deeper than 35 inches. Content of clay in the control section is 10 to 17 percent. Rock fragments range from 0 to 2 percent in the surface, 0 to 5 percent in the upper part of solum, 15 to 50 percent in the lower part of solum and 30 to 90 percent in the substratum. Content of rock fragments in the control section is 5 to 15 percent. Kind of rock fragments are sedimentary and metamorphic shale, siltstone and sandstone, gravel and cobbles. In unlimed areas, reaction ranges from strongly acid to moderately acid in the solum and moderately acid to slightly acid in the substratum.
The Ap horizon has hue of 5YR to 10YR, value of 3 or 4, and chroma of 3 or 4. It is very fine sandy loam, loam, or silt loam in the fine earth fraction. Structure is weak or moderate, fine or medium, granular or subangular blocky. Consistence is very friable or friable.
The BE horizon (if it occurs) has hue of 5YR or 7.5YR, value of 5, and chroma of 4 to 6. It is very fine sandy loam, loam, or silt loam in the fine earth fraction. Structure is moderate medium subangular blocky. Consistence is friable or firm.
The Bt horizon has hue of 5YR to 7.5YR, value of 4 or 5, and chroma of 4. It is silt loam or loam in the fine earth fraction. Structure is weak or moderate, fine or medium subangular blocky. Consistence is friable or firm.
The 2Btb horizon has hue of 2.5YR to 7.5YR, value of 4 or 5, and chroma of 2 to 6. It is silt loam, silty clay loam, or loam in the fine earth fraction. Structure is moderate medium or coarse subangular blocky. Consistence is firm.
The 2C horizon (if it occurs) has hue of 2.5YR or 5YR, value of 3 or 4, and chroma of 3 or 4. It is silt loam or loam in the fine earth fraction. Structure is massive. Consistence is firm or very firm.
The 2Cr horizon has hue of 2.5YR or 5YR, value of 3 or 4, and chroma of 3 or 4. It is silt loam or loam in the fine earth fraction. Structure is massive. Consistence is firm or very firm.
COMPETING SERIES: The Alvin, Boyer, Burnsville, Council, Dryden, Eleva, Elmdale, Hillsdale, Lamont, Lapeer, Mecan, Oshtemo, Perrin and Wyocena soils are in the same family. Alvin soils contain more than 50 percent fine sand and very fine sand in the control section. Boyer and Perrin soils are underlain by sand and gravel within 60 inches. Burnsville soils contain textures of sand and coarse sand within depth of 60 inches. Council soils formed in loamy deposits derived from loess deposits. Dryden, Lapeer and Perrin soils contain free carbonates at depths of 20 to 40 inches. Eleva soils have a paralytic contact between 20 to 40 inches. Elmdale soils have redox depletions of chroma 2 or less in the lower part of the subsoil. Hillsdale soils contains less than 50 percent fine sand and very fine sand and averages less than 18 percent clay in the control section. Lamont soils do not have free carbonates within depths of 60 inches. Mecan soils have hues redder than 7.5YR in the upper part of the series control section. Oshtemo and Wyocena soils contain more than 85 percent sand in the lower part of the solum. Oshtemo soils are not clearly differentiated, since it allows a loamy substratum phase. With the recent revision in the series control section, this phase will become a proposed series at a later date.
GEOGRAPHIC SETTING: Brownsburg soils are on hills in the Northern piedmont Province. The soils are on summits and back slopes. They are formed in a thin mantle of loess and in the underlying material weathered from red metamorphic shale and siltstone residuum. Slope ranges from 0 to 15 percent. Mean annual precipitation is 42 to 45 inches. The mean annual air temperature is 45 to 63 degrees F. The frost-free days range from 155 to 190.
GEOGRAPHICALLY ASSOCIATED SOILS: These are Duncannon, Steinsbury, Lansdale, Lawrenceville, Penn, Bedington, Chalfont, Doylestown, Alton, Pope, Reaville, Fountainville and Klinesville soils are on nearby landscapes. Duncannon and Lawrenceville soils have less than 18 percent sands that are coarser than very fine sand in the control section. Alton, Klinesville, Pope and Steinsburg soils lack the argillic horizon. Reaville and Fountainville soils have redox depletions of chroma 2 or less in the upper argillic horizon. Klinesville soils are less than 20 inches to bedrock. Chalfont and Doylestown soils have redox depletions of chroma 2 or less directly below the surface layer. Bedington and Penn soils which do not have the thin loess mantle. Lansdale soils contain more sand and coarse fragments. Fountainville soils have a loess mantle less than 24 inches.
DRAINAGE AND PERMEABILITY: Well drained. Surface runoff is slow to rapid. Permeability is moderate.
USE AND VEGETATION: Approximately 40 percent of the Brownsburg soils are in cropland, 30 percent are in pasture or hayland and 30 percent are in woodland or idle reverting to woodland. Wooded areas are mixed hardwoods.
DISTRIBUTION AND EXTENT: Pennsylvania. The series is of moderate extent.
MLRA SOIL SURVEY REGIONAL OFFICE (MO) RESPONSIBLE: Morgantown, West Virginia
PROPOSED SERIES: Bucks County, Pennsylvania, 1993.
REMARKS: Diagnostic horizons and features in this pedon include: Ochric epipedon - the zone from the surface to a depth of 10 inches (Ap horizon).
Argillic horizon - the zone from 10 to 44 inches (Bt1, Bt2, and 2Btb horizons).
Soils were previously mapped as an inclusion with Pope, Duncannon, Readington, Bedington, Penn, Lawrenceville, and Doylestown series.
ADDITIONAL DATA: Partial reference samples from pedon 93PA017005 from Bucks County, Pennsylvania.