LOCATION KOLIN LA+MSEstablished Series
TAXONOMIC CLASS: Fine-silty, siliceous, active, thermic Glossaquic Paleudalfs
TYPICAL PEDON: Kolin silt loam - pine plantation. (Colors are for moist soil.)
A--0 to 5 inches; dark grayish brown (10YR 4/2) silt loam; weak fine granular structure; friable; many coarse, medium, and fine roots; slightly acid; clear wavy boundary. (3 to 7 inches thick)
E--5 to 8 inches; pale brown (10YR 6/3) silt loam; weak medium subangular blocky structure; friable; many medium and fine roots; moderately acid; clear smooth boundary. (0 to 6 inches thick)
Bt1--8 to 14 inches; strong brown (7.5YR 5/6) silty clay loam; few fine faint pink redox concentration; moderate medium subangular blocky structure; firm; few fine roots; few fine pores; few distinct clay films on faces of peds; strongly acid; clear wavy boundary.
Bt2--14 to 19 inches; strong brown (7.5YR 5/6) silty clay loam; common fine distinct yellowish red and pink redox concentrations; moderate medium subangular blocky structure; firm; few fine roots; few fine pores; few distinct clay films on faces of peds; gray clay depletions up to 1 mm thick on faces of peds in lower part of horizon; strongly acid; abrupt irregular boundary. (Combined thickness of Bt horizon is 10 to 20 inches.)
Bt/E--19 to 24 inches; strong brown (7.5YR 5/6) silty clay loam (Bt); many coarse faint light brown (7.5YR 6/4) and few fine distinct red (2.5YR 5/6) redox concentrations; strong moderate and coarse subangular blocky structure; firm; few fine roots; few fine pores; light gray (10YR 7/1) albic materials and clay depletions 2 to 10 mm thick surrounding peds make up about 20 percent of horizon (E); few distinct clay films on faces of peds; strongly acid; clear irregular boundary. (5 to 15 inches thick)
2Bt1--24 to 37 inches; strong brown (7.5YR 5/6) silty clay; many coarse prominent red (2.5YR 5/6) masses of oxidized iron and common coarse distinct light gray (10YR 7/2) iron depletions; strong medium subangular blocky structure; very firm; thin continuous clay films on vertical and horizontal faces of peds; very strongly acid; gradual wavy boundary. (10 to 20 inches thick)
2Bt2--37 to 66 inches; red (2.5YR 5/6) clay; common medium prominent light gray (10YR 7/2) iron depletions; moderate medium subangular blocky structure; firm; light yellowish brown (10YR 6/4) silt coats up to 1 mm thick on some peds; thin patchy clay films on faces of peds; slightly acid; gradual wavy boundary. (8 to 30 inches thick)
2Bt3--66 to 80 inches; yellowish red (5YR 5/6) clay; many coarse distinct pinkish gray (5YR 7/2) iron depletions; moderate coarse subangular blocky structure; very firm; thin patchy clay films on faces of peds; slightly acid.
TYPE LOCATION: Rapides Parish, Louisiana; 1.5 miles north of Kolin, Louisiana from the intersection of LA107 and parish road, 66 feet west of ditch embankment; SE 1/4, NE 1/4, sec. 30, T4N, R1E; USGS Libuse 7.5 minute series topographic quadrangle; lat. 31 degrees 17 minutes 45 seconds N. and long. 92 degrees 18 minutes 49 seconds W.
RANGE IN CHARACTERISTICS: Solum thickness ranges from 60 to 100 inches. Depth to 2Bt horizon ranges from 20 to 40 inches.
The A or Ap horizon has value of 3 or 4 and chroma of 1 or 2 or value of 4 with chroma of 3. Where the value is 3, the A horizon is less than 6 inches thick. It is silt loam or loam. Reaction ranges from strongly acid to slightly acid, except in limed areas.
The E horizon, where present, has value of 5 or 6 and chroma of 1 to 4. Reaction ranges from very strongly acid to slightly acid.
A BE horizon is present in some pedons and has hue of 7.5YR or 10YR, value of 5 or 6 and chroma of 6. Redoximorphic concentrations in shades of red, pink, or brown, and clay depletions in shades of gray range from few to many. It is silty clay loam or silt loam with 20 to 35 percent clay. It is very strongly acid to moderately acid.
The Bt horizon has hue of 7.5YR or 10YR, value of 5 or 6 and chroma of 4 to 8. Redoximorphic concentrations in shades of red, pink, or brown, and clay depletions in shades of gray range from few to many within a depth of 30 inches. Texture is silty clay loam or silt loam with 20 to 35 percent clay. Reaction is very strongly acid to moderately acid.
The Bt part of the Bt/E horizon has hue of 7.5YR to 2.5Y, value of 4 or 5, and chroma of 4 to 8; the E parts have hue of 10YR or 2.5Y, value of 5 to 7, and chroma of 1 or 2, and occur as silt coatings and clay depletions that are vertical intrusions between structural units. Redoximorphic concentrations in shades of red, brown, or yellow range from none to common, and iron or clay depletions in shades of gray range from 5 to 20 percent. Texture of the Bt part is silty clay loam or silt loam. Some pedons have an E/B horizon.
The 2Bt has hue of 2.5YR to 2.5Y, value of 4 or 5, and chroma of 4 to 8, or it is variegated with these colors and shades of gray. Some pedons have a thin 2Btg horizon with hue of 2.5YR to 2.5Y, value of 4 or 5, and chroma of 2 at the upper part of the discontinuity. Slickensides or pressure faces are present in the horizon in some pedons. Texture is clay or silty clay. Reaction is very strongly acid through moderately alkaline.
The C horizon, where present, is variegated in shades of red, brown, and gray. Reaction ranges from very strongly acid to moderately alkaline.
COMPETING SERIES: These are the Abita and Glenmora series in the same family. Other series in closely related families are the Beauregard, Elysian, Evangeline, Keithville, Metcalf, Muskogee, and Timpson soils. Abita and Glenmora soils do not have a clayey discontinuity within a depth of 40 inches. In addition, Glenmora soils do not have a Glossic horizon. Beauregard soils have 5 to 30 percent plinthite in the B horizon. Elysian and Timpson soils have less than 18 percent clay in their particle-size control section. Evangeline soils do not have aquic conditions within a depth of 40 inches. Metcalf soils formed in alluvial sediments over Tertiary age clayey deposits that do not have reddish matrix color, and have a semiactive activity class. Muskogee soils do not have intrusions of albic materials within the argillic horizon. Keithville soils contain more than 25 percent total sand in the argillic horizon.
GEOGRAPHIC SETTING: Kolin soils are on uplands and terraces of Pleistocene Age. Slope gradients range from 1 to 8 percent. The soil formed in silty sediments overlying clayey sediments. Near the type location, average annual temperature is about 65 degrees F, and average annual precipitation is about 56 inches.
GEOGRAPHICALLY ASSOCIATED SOILS: These are the competing Beauregard and Glenmora series and the Acadia, Crowley, Gore, Libuse, Lorman, and Wrightsville series. Acadia, Crowley, Gore, Lorman, and Wrightsville soils have fine-textured control sections. Libuse soils have a fragipan.
DRAINAGE AND PERMEABILITY: Somewhat poorly drained; rate of runoff is medium on slopes less than 1 percent, high on slopes less than 5 percent, and very high on slopes of 5 percent or more; moderately slow permeability in the Bt horizon and very slow in the 2Bt horizon. The soil is wet in the layers below 1.5 to 3 feet and above the clayey 2Bt horizon during December through April in normal years.
USE AND VEGETATION: Most of the areas of this soil is in mixed hardwood and pine woodland. A small acreage is used for pasture and cultivated crops.
DISTRIBUTION AND EXTENT: Arkansas, Louisiana, Mississippi, and possibly Oklahoma. Extent is moderate.
MLRA OFFICE RESPONSIBLE: Little Rock, Arkansas
SERIES ESTABLISHED: Rapides Parish, Louisiana, 1972.
REMARKS: The Kolin series was first proposed as fine-silty, siliceous, thermic Glossaquic Paleudalfs and submitted for review in 1972 with change in the definition of "a glossic horizon". With further examination of pedons the concept was changed to a fine-silty, siliceous thermic Haplic Glossudalf. The series was updated in 2004 to change the classification back to a Glossaquic Paleudalf based on changes made to the 9th ed. Keys to Taxonomy which places Paleudalfs higher on the key than Glossudalfs, and on water monitoring data at a site in Bossier Parish, Louisiana. Further study is still needed to verify that the correct mineralogy class for Kolin soils is siliceous. Some data from Bossier Parish indicate that it may be mixed. The series was also updated in 2004 to allow 2.5Y hue in the Glossic horizon and in the 2Bt horizon, and to allow a gray matrix in the parts of the subsoil just below the discontinuity.
Diagnostic horizons and features in this pedon:
Ochric epipedon.......0 to 8 inches (A and E horizons)
Albic horizon................5 to 8 inches (E horizon)
Argillic horizon...8 to 80 inches (Bt1, Bt2, B1E, 2Bt1, 2Bt2, and 2Bt3 horizons)
Glossic horizon..........19 to 24 inches (B/E horizon)