LOCATION SILOAM             NC+VA
Established Series
RJL-DCC/Rev. JAK
03/2006

SILOAM SERIES


MLRA(s): 136 (mesic part)
MLRA SOIL SURVEY REGIONAL OFFICE (MO) RESPONSIBLE: Raleigh, North Carolina
Depth Class: Shallow to soft bedrock and moderately deep to hard bedrock
Drainage Class (Agricultural): Well drained
Internal Free Water Occurrence: Very deep
Flooding Frequency and Duration: None
Ponding Frequency and Duration: None
Index Surface Runoff: Medium to very high
Permeability: Moderately slow
Shrink-Swell Potential: Moderate
Landscape: Piedmont upland
Landform: Hill, interfluve, ridge
Geomorphic Component: Crest, side slope, nose slope, head slope
Hillslope Profile Position: Summit, shoulder, backslope
Parent Material: Residuum weathered from mafic metamorphic or igneous rock
Slope: 2 to 60 percent
Elevation (type location): 940 feet
Frost Free Period (type location): 174 days
Mean Annual Air Temperature (type location): 57 degrees F.
Mean Annual Precipitation (type location): 46 inches

TAXONOMIC CLASS: Loamy, mixed, superactive, mesic, shallow Typic Hapludalfs

TYPICAL PEDON: Siloam fine sandy loam (in an area of Siloam-Redbrush complex, 6 to 15 percent slope), on a convex 7 percent slope in hayland. (Colors are for moist soil unless otherwise indicated.)

Ap--0 to 20 centimeters (0.0 to 7.9 inches); dark yellowish brown (10YR 3/4) fine sandy loam, dark yellowish brown (10YR 4/4), dry; weak medium granular structure; friable, nonsticky, nonplastic; many fine roots throughout; common fine tubular pores; 15 percent fine mica flakes throughout; 10 percent 2- to 75-millimeter quartz fragments; neutral, pH 7.0, Hellige-Truog; 15 percent coarse distinct dark yellowish brown (10YR 4/4) bodies of B horizon soil material throughout; clear wavy boundary. (2 to 10 inches thick)

Bt--20 to 33 centimeters (7.9 to 13.0 inches); dark yellowish brown (10YR 4/6) sandy clay loam; moderate coarse angular blocky structure; friable, moderately sticky, moderately plastic; common fine roots throughout; few fine tubular pores; 10 percent discontinuous distinct yellowish brown (10YR 5/4) clay films on vertical faces of peds; 10 percent fine distinct irregular yellowish brown (10YR 5/8) masses of oxidized iron between peds; 15 percent fine mica flakes throughout; 5 percent 2- to 75-millimeter gneiss fragments and 5 percent 2- to 75-millimeter quartz fragments; neutral, pH 7.0, Hellige-Truog; 15 percent moderate-continuity distinct dark brown (10YR 3/3) fillings of A horizon soil material in old root channels and between peds; clear irregular boundary. (3 to 15 inches thick)

Bt/C--33 to 38 centimeters (13.0 to 15.0 inches); 80 percent dark yellowish brown (10YR 4/6) sandy clay loam; moderate coarse angular blocky structure; friable, moderately sticky, moderately plastic; common fine roots throughout; few fine tubular pores; 10 percent discontinuous distinct yellowish brown (10YR 5/4) clay films on vertical faces of peds; 10 percent fine distinct irregular yellowish brown (10YR 5/8) masses of oxidized iron between peds; 15 percent fine mica flakes throughout; 5 percent 2- to 75-millimeter quartz fragments and 5 percent 2- to 75-millimeter gneiss fragments; neutral, pH 7.0, Hellige-Truog; coarse soil peds part along relic rock fractures; 15 percent moderate-continuity distinct dark brown (10YR 3/3) fillings of A horizon soil material in old root channels and between peds (Bt part); 20 percent pockets of massive; friable; green, brown, gray, white, and black loamy saprolite (C part); abrupt irregular boundary. (0 to 10 inches thick)

Cr--38 to 66 centimeters (15.0 to 26.0 inches); soft gneiss bedrock, fractured at intervals of 4 to less than 18 inches; weakly cemented; moderate excavation difficulty; abrupt irregular boundary.

R--66 centimeters (26.0 inches); hard gneiss bedrock, fractured at intervals of 4 to less than 18 inches; very strongly cemented; very high excavation difficulty.

TYPE LOCATION: Surry County, North Carolina; from the intersection of Secondary Roads 1003 and 2085, southeast 0.8 mile on Secondary Road 1003, east 0.6 mile of Secondary Road 1003, in fescue hayland; Siloam USGS topographic quadrangle; lat. 36 degrees 18 minutes 10 seconds N. and long. 80 degrees 34 minutes 19 seconds W.

RANGE IN CHARACTERISTICS:
Depth to top of Argillic horizon: 1 to 10 inches
Depth to base of Argillic horizon: 10 to 20 inches
Depth to bedrock: 10 to 20 inches to soft bedrock, 20 to 40 inches to hard bedrock
Rock Fragment Content: 0 to 35 percent, by volume throughout; mostly quartz or gneiss gravel, cobbles, and stones
Soil Reaction: Strongly acid to slightly acid in the upper horizons and moderately acid to mildly alkaline in the lower horizons
Mica Content: 0 to 20 percent, by volume throughout
Other Features: 0 to 20 percent, by volume throughout dark manganese concretions or nodules

RANGE OF INDIVIDUAL HORIZONS:
Ap horizon or A horizon (if it occurs):
Color--hue of 7.5YR to 5Y, value of 3 to 5, chroma of 2 to 6
Texture (fine-earth fraction)--sandy loam, fine sandy loam, or loam. Eroded phases include sandy clay loam or clay loam.

E horizon (if it occurs):
Color--hue of 7.5YR to 2.5Y, value of 4 to 6, chroma of 3 to 6
Texture (fine-earth fraction)--sandy loam, fine sandy loam, or loam

Bt horizon:
Color--hue of 5YR to 2.5Y, value of 4 to 6, chroma of 4 to 8
Texture (fine-earth fraction)--loam, sandy clay loam, clay loam, or clay
Non-redoximorphic mottles (if they occur)--masses in shades of black, green, gray, or white, mostly saprolite.

Bt/C horizon:
Bt part--same properties as Bt horizon
C part--same properties as C horizon
C horizon (if it occurs):
Color--hue of 5YR to 5Y, value of 4 to 6 chroma of 4 to 8, or variegated shade of these colors
Texture (fine-earth fraction)--sandy loam, fine sandy loam, or loam saprolite

C/B horizon (if it occurs):
C part--same properties as C horizon
B part--same properties as Bt horizon
Some pedons have seams of clayey soil material filling relict rock fractures and old root channels.

Cr horizon:
Bedrock kind--intermediate or mafic crystalline rock or igneous rock
Bedrock hardness--extremely weakly cemented to moderately cemented
Fracture interval--greater than 4 inches
Excavation difficulty--low to high

R horizon:
Bedrock kind--intermediate or mafic crystalline rock or igneous rock
Bedrock hardness--strongly cemented to indurated
Fracture interval--greater than 4 inches
Excavation difficulty--very high or extremely high

COMPETING SERIES: None

GEOGRAPHIC SETTING:
Landscape: Piedmont upland
Landform: Hill, interfluve, ridge
Geomorphic Component: Crest, side slope, nose slope, head slope
Hillslope Profile Position: Summit, shoulder, backslope
Parent Material: Residuum weathered from mafic metamorphic or igneous rock high in ferromagnesian minerals
Slope: 2 to 60 percent
Elevation: 300 to 1,400 feet
Mean Annual Air Temperature: 52 to 57 degrees
Mean Annual Precipitation: 40 to 55 inches
Frost Free Period: 160 to 205 days

GEOGRAPHICALLY ASSOCIATED SOILS:
Halifax soils--are greater than 60 inches to bedrock; on similar landforms
Haymarket soils--are greater than 60 inches to bedrock; on similar landforms
Jackland soils--have iron depletions in the upper part of the subsoil; on lower-lying landforms
Mirerock soils--have hard bedrock at 40 to 60 inches; on similar landforms
Redbrush soils--have hard bedrock at 20 to 40 inches; on similar landforms
Spriggs soils--have a fine-loamy particle-size control section clay; on similar landforms

DRAINAGE AND PERMEABILITY:
Depth Class: Shallow ( 10 to 20 inches) to soft bedrock
Drainage Class (Agricultural): Well drained
Internal Free Water Occurrence: Very deep
Flooding Frequency and Duration: None
Ponding Frequency and Duration: None
Index Surface Runoff: Medium to very high
Permeability: Moderately slow
Shrink-Swell Potential: Moderate
USE AND VEGETATION:
Major Uses: Predominantly hayland and pasture, and to a lesser extent woodland and cultivated crops
Dominant Vegetation: Where cultivated--corn, small grain, soybeans, tobacco, and lespedeza. Where wooded--shortleaf pine, Virginia pine, eastern red cedar, blackjack oak, and post oak.

DISTRIBUTION AND EXTENT:
Distribution: North Carolina and Virginia
Extent: Small

MLRA SOIL SURVEY REGIONAL OFFICE (MO) RESPONSIBLE: Raleigh, North Carolina

SERIES ESTABLISHED: Surry County, North Carolina; 2003.

REMARKS: Siloam soils were previously mapped as Wilkes soils. The April 1997 relocation of the mesic/thermic line in North Carolina and Virginia necessitated the establishment of a mesic counterpart.

Diagnostic horizons and soil characteristics recognized in this pedon:
Ochric epipedon--the zone from the surface to 10 inches (Ap horizon)
Argillic horizon--the zone from 10 to 15 inches (Bt horizon)
Paralithic contact--the contact at 15 inches (Cr horizon)
Paralithic materials--the zone from 15 to 26 inches (Cr horizon)
Other soil features identified with this pedon:
Presence of hard bedrock at 26 inches (R horizon)
Series control section--the zone from 0 to 25 inches

ADDITIONAL DATA:
Laboratory Data: No laboratory data available.
Database Information:
Typical Pedon Data Mapunit ID--82678
User Pedon ID--Siloam-OSD Surry County, NC

TABULAR SERIES DATA:

Slope Airtemp FrFr/Seas Precip Elevation
2-60 52-57 160-205 40-55 300-1400 

FloodL FloodH Watertable Kind Months Bedrock Hardness NONE >6.0 - - 10-20 SOFT

Depth Texture 3-Inch No-10 Clay% -CEC- 0-8 SL FSL L 0-10 75-100 5-20 4-6 0-8 SCL CL L 0-10 75-100 20-35 4-12 0-8 GR-SL GR-L GR-FSL 5-15 50-75 5-20 4-10 8-15 CL C SCL L 0-10 50-100 10-45 6-18 15-26 WB - - - - 26 UWB - - - -

Depth -pH- O.M. Salin Permeab Shnk-Swll 0-8 5.1-6.5 0.5-2 0.0 2.0-6.0 LOW 0-8 5.1-6.5 0.5-1 0.0 0.6-2.0 MODERATE 0-8 5.1-6.5 0.5-2 0.0 2.0-6.0 LOW 8-15 5.6-7.8 0-0.5 0.0 0.2-0.6 MODERATE 15-26 - - 0.0 0.06-0.2 - 26 - - 0.0 <0.06 -


National Cooperative Soil Survey
U.S.A.