LOCATION PICTURE NCEstablished Series
TAXONOMIC CLASS: Fine, smectitic, thermic Vertic Argiaquolls
TYPICAL PEDON: Picture loam--woodland. (Colors are for moist soil unless otherwise stated.)
A--0 to 3 inches; very dark gray (10YR 3/1) loam; gray (10YR 5/1) dry; moderate fine granular structure; very friable; slightly sticky, non-plastic; common fine and medium roots; common fine pores; very strongly acid; clear smooth boundary. (2 to 12 inches thick)
AB--3 to 7 inches; very dark grayish brown (10YR 3/2) loam; grayish brown (10YR 5/2) dry; few fine distinct strong brown (7.5YR 4/6) mottles; moderate fine subangular blocky structure; friable; slightly sticky, slightly plastic; few fine and medium roots; common fine pores; common fine distinct black concretions; strongly acid; gradual wavy boundary. (0 to 10 inches thick)
Btg1--7 to 17 inches; very dark grayish brown (10YR 3/2) clay loam, dark gray (10YR 4/1) dry; weak coarse subangular blocky structure; firm; moderately sticky, moderately plastic; few fine and medium roots; few fine pores; few distinct clay films on faces of peds and in pores; common fine and medium distinct black concretions; moderately acid; clear wavy boundary.
Btg2--17 to 24 inches; dark grayish brown (2.5Y 4/2) clay; weak coarse subangular blocky structure; very firm; very sticky, very plastic; few fine roots; common very fine pores; common distinct clay films on faces of peds and in pores; few fine and medium distinct black concretions; slightly acid; clear wavy boundary. (Combined thickness of the Btg horizon is 15 to 30 inches)
BCg--24 to 31 inches; mottled 55 percent dark grayish brown (2.5Y 4/2), 25 percent light olive brown (2.5Y 5/4), and 20 percent strong brown (7.5YR 5/8) clay; weak medium and coarse subangular blocky structure; firm; moderately sticky, moderately plastic; few fine roots; few fine pores; common fine and medium black concretions; 10 percent by volume gravel; neutral; gradual wavy boundary. (0 to 20 inches thick)
Cg--31 to 49 inches; mottled 65 percent dark grayish brown (2.5Y 4/2), 20 percent light olive brown (2.5Y 5/4), and 15 percent strong brown (7.5YR 5/8) sandy loam; massive; friable; slightly sticky, non-plastic; 5 percent by volume gravel; slightly alkaline; gradual wavy boundary. (0 to 20 inches thick)
Cr--49 to 62 inches; weathered, multicolored diabase bedrock that can be dug with difficulty with a spade.
TYPE LOCATION: Granville County, North Carolina; 0.2 mile northwest of Butner on Secondary Road 1103, 0.6 mile southwest on Secondary Road 1111, 200 feet southeast of the road in a wooded area; Creedmoor USGS topographic quadrangle, lat. 36 degrees 07 minutes 18 seconds, long. 78 degrees 44 minutes 57 seconds.
RANGE IN CHARACTERISTICS: Solum thickness ranges from 20 to 50 inches. Depth to paralithic contact with soft, weathered bedrock (Cr) ranges from 40 to 60 inches. Depth to lithic contact with hard, unweathered bedrock (R) is greater than 60 inches. Most pedons have few to many black or dark colored iron-manganese concretions. Content of coarse fragments, mostly gravel size, is less than 35 percent by volume in the A horizon and less than 15 percent in the B and C horizons. Content of mica is none or few. Some pedons have few to common slickensides in the lower B horizon. Soil reaction ranges from very strongly acid to neutral in the A and B horizon and from moderately acid to slightly alkaline in the C horizon.
The A or Ap horizon has hue of 10YR or 2.5Y, value of 2 or 3, and chroma of 1 to 3. Mottles, if they occur, are in shades of brown, yellow, olive, or gray. Texture of the fine-earth fraction of the A horizon is loam, fine sandy loam, or sandy loam.
The AB or BA horizon has hue of 10YR or 2.5Y, value of 2 to 4, and chroma of 1 to 3. Mottles, if they occur, are in shades of brown, yellow, olive, or gray. Texture of the BA or AB horizon is loam, fine sandy loam, sandy loam, clay loam, or sandy clay loam.
The Btg or Btssg horizon has hue of 10YR to 5Y, value of 3 to 6, and chroma of 1 or 2; or hue of N, value of 4 to 7. Mottles, if they occur are in shades of brown, yellow, olive, or gray. Texture of the Btg horizon is clay, sandy clay, clay loam, or silty clay.
The BCg horizon has hue of 10YR to 5Y, value of 3 to 8, and chroma of 1 or 2; or hue of N, value of 4 to 8. Mottled pedons dominantly have chroma of 2 or less. Mottles, if they occur, are in shades of brown, yellow, olive, or gray. Texture of the BCg horizon is clay, sandy clay, silty clay, sandy clay loam, or clay loam.
The BC horizon, where present, has hue of 7.5YR to 5Y, value of 4 to 8, and chroma of 3 to 8, or may be mottled in shades of these colors. Mottles, if they occur, are in shades of brown, yellow, olive, or gray. Texture of the BC horizon is clay, sandy clay, silty clay, sandy clay loam, or clay loam.
The Cg horizon is saprolite, and has hue of 10YR to 5Y, value of 3 to 8, and chroma of 1 or 2; or hue of N, value of 4 to 8. Mottled pedons dominantly have chroma of 2 or less. Mottles, if they occur, are in shades of brown, yellow, olive, or gray. Texture is sandy clay, silty clay, sandy clay loam, clay loam, or sandy loam.
The C horizon, where present, is saprolite and has hue of 7.5YR to 5Y, value of 4 to 8, and chroma of 3 to 8, or may be mottled in shades of these colors. Some pedons have mottles in shades of brown, yellow, olive, or gray. Texture of the C horizon is sandy clay, silty clay, sandy clay loam, clay loam, or sandy loam.
The Cr horizon is weathered, multicolored mafic rock. It is commonly diabase. Fractures between the rocks are more than 4 inches apart and may contain loamy or sandy soil material.
COMPETING SERIES: Bernard, Fiat, and Mayes are the only competing series in the same family. These soils are somewhat poorly drained. In addition, Bernard soils are more than 60 inches to bedrock and have sola greater than 60 inches, Fiat soils are 20 to 40 inches to bedrock, and Mayes soils are more than 60 inches to bedrock.
GEOGRAPHIC SETTING: Picture soils are on upland flats and depressions of Piedmont Uplands. Slopes range from 0 to 3 percent, but are commonly less than 2 percent. These soils formed in materials weathered from mafic rocks, commonly diabase in dikes and sills. The average annual rainfall ranges from 38 to 50 inches, the frost-free season ranges from 184 to 226 days, and the mean annual air temperature ranges from 59 to 71 degrees F.
GEOGRAPHICALLY ASSOCIATED SOILS: These are the Creedmoor, Enon, Iredell and Orange series. Creedmoor soils are moderately well drained to somewhat poorly drained and have mixed mineralogy. They formed in Triassic material adjacent to the mafic dikes and sills that Picture soils formed in. Enon soils are well drained and have mixed mineralogy. Iredell soils are moderately well drained and have montmorillonitic mineralogy. Orange soils are moderately well drained to somewhat poorly drained. All these soils are on higher landscape positions than Picture soils.
DRAINAGE AND PERMEABILITY: Poorly drained; slow runoff; and very slow permeability.
USE AND VEGETATION: Most areas are in pasture or woodland. The tree species are commonly water tolerant hardwoods and pines. Some areas are in corn, cotton, or soybeans.
DISTRIBUTION AND EXTENT: The Piedmont areas of North Carolina and possibly South Carolina, Alabama, Georgia, and Virginia. The series is of small extent.
MLRA SOIL SURVEY REGIONAL OFFICE (MO) RESPONSIBLE: Raleigh, North Carolina
SERIES ESTABLISHED: Granville County, North Carolina; 1993.
REMARKS: The Picture series was originally classified as fine, montmorillonitic, thermic Abruptic Agriaquolls but was changed in 1991 to Typic Argiaquolls based on transects and laboratory data from four pedons. The mineralogy of Picture soils by X-ray diffraction is marginal between mixed and montmorillonitic. However, CEC values per 100 grams of clay exceeds 50 throughout the control section and the CEC/clay ratio ranges from 0.5 to 0.9 for the type location. Available COLE values of the subsoil ranges from 0.10 to 0.15. This data indicates mineralogy would best be placed in a montmorillonitic family. The classification was changed in 1993 to Vertic Argiaquolls based on changes in taxonomic criteria for "Vertic" subgroups issued in the 1992 Keys to Soil Taxonomy.
Diagnostic horizons and soil characteristics recognized in this pedon are:
Mollic epipedon - the zone from the surface of the soil to 17 inches (A, AB, and Btg1 horizon)
Argillic horizon - the zone from 7 to 31 inches (Btg1, Btg2, and BCg horizons)
SIR = NC0216 MLRA = 136
ADDITIONAL DATA: Characterization data is available from the National Soil Survey Laboratory for the type location (S86NC-077-001) and three additional pedons (S86NC-077-002; S86NC-077-003; and S88NC-077-005).
TABULAR SERIES DATA:
SOI-5 Soil Name Slope Airtemp FrFr/Seas Precip Elevation NC0216 PICTURE 0- 3 59- 71 184-226 38- 50 300- 450SOI-5 FloodL FloodH Watertable Kind Months Bedrock Hardness NC0216 NONE 0.5-1.5 PERCHED NOV-APR 40-60 SOFT
SOI-5 Depth Texture 3-Inch No-10 Clay% -CEC- NC0216 0- 7 L FSL SL 0- 1 75-100 7-27 15- 25 NC0216 0- 7 CL SCL 0- 1 75-100 27-40 15- 30 NC0216 0- 7 GR-L GR-FSL GR-SL 0- 5 60- 75 7-27 15- 25 NC0216 7-31 C CL SC 0- 1 75-100 30-60 25- 45 NC0216 31-49 CL SCL SL 0- 1 75-100 15-30 25- 45 NC0216 49-62 WB - - - -
SOI-5 Depth -pH- O.M. Salin Permeab Shnk-Swll NC0216 0- 7 5.1- 7.3 2.-8. 0- 0 0.6- 2.0 LOW NC0216 0- 7 5.1- 7.3 2.-8. 0- 0 0.06- 0.6 MODERATE NC0216 0- 7 5.1- 7.3 2.-8. 0- 0 0.6- 2.0 LOW NC0216 7-31 5.6- 7.8 0.-.5 0- 0 0.0-0.06 VERY HIGH NC0216 31-49 5.6- 7.8 0.-.5 0- 0 0.06- 0.2 MODERATE NC0216 49-62 - - - 0.00- 20