LOCATION PIKECITY AREstablished Series
TAXONOMIC CLASS: Fine-loamy, siliceous, semiactive, thermic Typic Hapludults
TYPICAL PEDON: Pikecity silt loam, 1 to 6 percent slopes, in forest. (Colors are for moist soil unless otherwise stated.)
A--0 to 8 cm (0 to 3 in); dark brown (10YR 3/3) silt loam; weak fine granular structure; very friable; many fine to coarse roots throughout; common fine and medium pores; few prominent patchy black (10YR 2/1) stains on faces of peds; 10 percent rounded sandstone gravel; strongly acid; abrupt smooth boundary.
BA--8 to 15 cm (3 to 6 in); strong brown (7.5YR 5/6) silt loam; weak fine subangular blocky structure; friable; common fine to coarse roots throughout; common fine pores; 10 percent rounded sandstone gravel; very strongly acid; clear smooth boundary.
Bt1--15 to 56 cm (6 to 22 in); red (2.5YR 4/6) clay loam; moderate medium and coarse subangular blocky structure; firm; common fine roots and common medium roots throughout; common fine pores; common faint discontinuous red (2.5YR 5/6) clay films on faces of peds and in pores; about 5 percent by volume rounded sandstone gravel; extremely acid; clear wavy boundary.
Bt2--56 to 79 cm (22 to 31 in); red (2.5YR 4/6) gravelly clay loam; moderate medium and coarse subangular blocky structure; firm; common fine roots, common medium roots, and common coarse roots throughout; common fine pores; common faint discontinuous red (2.5YR 5/6) clay films on faces of peds and in pores; about 15 percent by volume rounded sandstone gravel; extremely acid; gradual wavy boundary.
Bt3--79 to 122 cm (31 to 48 in); red (2.5YR 4/6) gravelly clay; moderate medium and coarse subangular blocky structure; firm; common fine and medium roots throughout; common fine pores; common faint discontinuous red (2.5YR 5/6) clay films on faces of peds and in pores; about 20 percent by volume rounded sandstone gravel and about 5 percent rounded sandstone cobbles; extremely acid; clear wavy boundary.
Bt4--122 to 203 cm (48 to 80 in); light gray (10YR 7/1), yellowish brown (10YR 5/8), and dark yellowish brown (10YR3/6) cobbly clay loam; moderate medium subangular blocky structure; firm; common faint patchy red (2.5YR 4/6) clay films on faces of peds and in pores; about 35 percent by volume rounded sandstone gravel and about 15 percent subrounded sandstone cobbles; extremely acid.
TYPE LOCATION: Pike County, Arkansas; about 1.5 miles west of Narrows Dam. SE14, NE1/4, SW1/4 Section. 14, T.7 S., R.26 W.; NARROWS DAM USGS topographic quadrangle; Latitude: 34 degrees, 8 minutes, 49 seconds North; Longitude: 93 degrees, 44 minutes, 49 seconds West.
RANGE IN CHARACTERISTICS: Solum thickness is more than 183 cm (72 in). Depth to horizons containing more than 35 percent by volume gravel begin at a depth of 76 cm (30 in) or deeper. Depth to horizon(s) containing more than 40 percent clay begin at a depths of 76 cn (30 in) or deeper. Reaction ranges from slightly acid to strongly acid in the A and BA horizons and strongly acid to extremely acid in the Bt and BC horizons. Coarse fragments range from 0 to 35 percent by volume in the A, E, BE, and upper Bt horizons and 15 to 60 percent in the lower Bt horizons and BC horizon.
A or Ap horizon:
Hue: 10YR
Value: 3 or 4
Chroma: 2 through 4
or Hue: 7.5YR
Value: 4
Chroma: 4
Texture: silt loam.
E horizon (where present):
Hue: 10YR
Value: 4 to 6
Chroma: 3 or 4
Texture: fine sandy loam, sandy loam, loam or silt loam or their gravelly analogs.
BA horizon:
Hue: 7.5YR
Value: 4 to 6
Chroma: 5 or 6
or Hue: 10YR
Value: 4 or 5
Chroma: 4 to 8
Texture: very fine sandy loam, loam or silt loam or their gravelly analogs.
Bt1 horizon:
Hue: 7.5YR
Value: 4 or 5
Chroma: 6 or 8
or Hue: 5YR
Value: 4 or 5
Chroma: 4 to 8
or Hue: 2.5YR
Value: 4 or 5
Chroma: 6 or 8
Texture: loam, clay loam, sandy clay loam, or their gravelly analogs.
Bt2 horizon:
Same colors as the Bt1 horizon
or Hue: 10R
Value: 3
Chroma: 6
Texture: sandy clay loam, clay loam, clay, or their gravelly analogs.
Bt3 horizon:
Same colors as the Bt2 horizon. Some pedons may not have a dominant matrix color, but are variegated in various shades of brown, red, and gray.
Texture: loam, sandy clay loam, clay loam, clay, or their gravelly, very gravelly or cobbly analogs.
Bt4 horizon:
Hue: 7.5YR
Value: 4 or 5
Chroma: 6 or 8
or Hue: 5YR
Value: 4 or 5
Chroma: 4 to 8
or Hue: 2.5YR
Value: 4 or 5
Chroma: 6 or 8
In many pedons, these horizons are variegated in various shades of brown, red , and gray.
Texture is loam, clay loam, sandy clay loam, or their gravelly, very gravelly, or cobbly analogs.
BC horizon (where present):
Hue: 7.5YR
Value: 4 or 5
Chroma: 6 or 8
or Hue: 5YR
Value: 4 or 5
Chroma: 4 to 8
or Hue: 2.5YR
Value: 4 or 5
Chroma: 6 or 8
In some pedons, these horizons are variegated in various shades of brown, red , and gray.
Texture: gravelly loam, gravelly clay loam, gravelly sandy clay loam, or their very gravelly, cobbly, or very cobbly analogs.
COMPETING SERIES: There are no competing series in this family.
GEOGRAPHIC SETTING: Pikecity soils are on marine terraces of the Cretaceous Western Gulf Coastal Plain, MLRA 135B. They formed in loamy and gravelly marine sediments. Slopes range from 1 to 15 percent. Mean annual precipitation ranges from 1143 to1397 cm (45 to 55 in). Mean annual temperature ranges from 17 to 23 degrees C (63 degrees to 75 degrees F). Thornthwaite annual P-E indices are greater than 64.
GEOGRAPHICALLY ASSOCIATED SOILS: These are the
Nathan,
Peanutrock and
Tiak series.
Nathan soils have a fine-loamy control section and have mixed mineralogy.
Peanutrock soils have a loamy-skeletal control section.
Tiak soils have a fine control section.
DRAINAGE AND PERMEABILITY: Pikecity soils are well drained. Runoff is low to medium and permeability is moderate.
USE AND VEGETATION: Used mainly for native pasture and woodland. The vegetation is primarily southern red oak, sweetgum, American sycamore, white oak, and loblolly pine.
DISTRIBUTION AND EXTENT: Cretaceous Western Gulf Coastal Plain of southwest Arkansas and possibly southeast Oklahoma. The series is of moderate extent.
MLRA SOIL SURVEY REGIONAL OFFICE (MO) RESPONSIBLE: Morgantown, West Virginia
SERIES ESTABLISHED: Pike County, Arkansas; 2006
REMARKS: Diagnostic horizons and features recognized in this pedon are:
Ochric epipedon: Surface to 8 cm (0 to 3 in)
Argillic horizon: 15 to 203 cm (6 to 80 in)
These soils were formerly included in the Pikeville series.
ADDITIONAL DATA: Characterization of the typical pedon by the University of Arkansas Soil Characterization Laboratory; S98AR-109-01.
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