LOCATION KAPLAN LA

Established Series
Rev. KEM-RM
02/2015

KAPLAN SERIES

The Kaplan series consists of very deep, somewhat poorly drained soils on abandoned meander scrolls on flat coastal plains. Slope ranges from 0 to 3 percent. Mean annual precipitation is about 1500 mm (59 in) and the mean annual air temperature is 20 degrees C (68 degrees F).

TAXONOMIC CLASS: Fine, smectitic, thermic Aeric Chromic Vertic Epiaqualfs

TYPICAL PEDON: Kaplan silt loam--cropland, on a nearly level ridge; elevation is 4 m (13 ft). (Colors are for moist soil unless otherwise stated)

Ap1--0 to 10 cm (0 to 4 in); dark grayish brown (10YR 4/2) silt loam; weak fine granular structure; friable; common fine and medium roots; slightly acid; abrupt smooth boundary.

Ap2--10 to 25 cm (4 to 10 in); dark grayish brown (10YR 4/2) silt loam; weak medium granular structure; friable; few fine roots; few fine distinct dark yellowish brown (10YR 4/4) iron concentrations; few prominent reddish brown (5YR 4/4) stains along root channels; neutral; abrupt smooth boundary. (Combined thickness of the Ap horizons is is 20 to 36 cm (8 to 11 in))

Btg1--25 to 41 cm (10 to 16 in); dark gray (10YR 4/1) silty clay loam; moderate medium subangular blocky structure; firm; few fine roots; few faint dark gray clay films on surfaces of peds; common medium iron-manganese concretions; few fine faint grayish brown (10YR 5/2) iron depletions; many yellowish brown (10YR 5/4) stains along root channels; neutral; clear smooth boundary.

Btg2--41 to 56 cm (16 to 22 in); dark grayish brown (10YR 4/2) silty clay; moderate medium subangular blocky structure; firm; few fine roots; common distinct dark gray (10YR 4/1) clay films on surfaces of peds; few fine black iron-manganese concretions; common medium prominent red (2.5YR 4/8) iron concentrations; neutral; gradual wavy boundary. (Combined thickness of the Btg horizons is 15 to 71 cm (6 to 28 in))

Btkg1--56 to 69 cm (22 to 27 in); light yellowish brown (2.5Y 6/4) silty clay ped interiors with gray (10YR 5/1) and dark gray (10YR 4/1) ped surfaces; moderate medium subangular blocky structure; firm; few fine roots; few fine vesicular pores; common faint gray (10YR 5/1) and dark gray (10YR 4/1) clay films on surfaces of peds; few fine black iron-manganese concretions; many medium distinct light brownish gray (2.5Y 6/2) iron depletions; many yellowish brown (10YR 5/6) and common fine prominent red (2.5YR 4/6) iron concentrations; few medium calcium carbonate concretions; moderately alkaline; gradual wavy boundary.

Btkg2--69 to 112 cm (27 to 44 in); light brownish gray (2.5Y 6/2) silty clay; moderate coarse prismatic structure parting to moderate medium subangular blocky; firm; few fine roots; common fine vesicular pores; common distinct gray (10YR 5/1) and dark gray (10YR 4/1) clay films on surfaces of peds; common fine black iron-manganese concretions; common medium prominent olive yellow (2.5Y 6/8) iron concentrations; common medium and coarse calcium carbonate concretions; moderately alkaline; gradual wavy boundary. (Combined thickness of the Btkg horizons is 56 to 79 cm (22 to 32 in))

Btkssg1--112 to 135 cm (44 to 53 in); light brownish gray (2.5Y 6/2) silty clay loam; moderate coarse prismatic structure parting to weak medium subangular blocky; firm; common fine vesicular pores; common distinct gray (10YR 5/1) clay films on vertical surfaces of peds; few medium and coarse black iron-manganese concretions; common fine prominent yellowish red (5YR 5/8) iron concentrations; common medium and coarse calcium carbonate concretions; few distinct slickensides; moderately alkaline; gradual wavy boundary. (Combined thickness of the Btkssg horizons is 73 to 112 cm (29 to 44 in))

Btkssg2--135 to 203 cm (53 to 80 in); gray (5Y 6/1) silty clay loam; moderate coarse subangular blocky structure; firm; common fine vesicular pores; few faint clay films on vertical surfaces of peds; common medium black iron-manganese concretions; many coarse prominent yellowish red (5YR 5/6) iron concentrations; common medium and coarse calcium carbonate concretions; few distinct slickensides; moderately alkaline.

TYPE LOCATION: Cameron Parish, Louisiana; From the intersection of LA Highway 99 and LA Highway 14 in Jefferson Davis Parish, 2.1 miles south on gravel road; 200 feet east of gravel road in cropland; Thornwell, LA USGS topographic quadrangle; Latitude: 30 degrees, 02 minutes, 11 seconds N; Longitude: 92 degrees, 49 minutes, 47 seconds W.; NAD 83.

RANGE IN CHARACTERISTICS:
Particle-size control section (weighted average)
Clay content: 35 to 50

Ap Horizon:
Hue: 10YR
Value: 4
Chroma: 1 to 3
Texture: silt loam
Clay content: 14 to 26 percent
Redox concentrations: amount-none to common, size-fine, contrast-distinct to prominent, location-on surfaces along root channels, shades-brown
Electrical conductivity (mmhos/cm): 0 to 4
Sodium Adsorption Ratio: 0 to 1
Reaction: moderately acid to moderately alkaline

Btg Horizon:
Hue: 10YR or 2.5Y
Value: 4 to 6
Chroma: 1 to 4
Texture: silty clay or silty clay loam
Clay content: 27 to 45 percent
Clay films: location on surfaces of peds, contrast faint or distinct
Redox concentrations: amount few to many, size-fine or medium, contrast-prominent, shades-red or brown
Redox depletions: amount-few, size-fine, contrast-faint, shades-brown
Electrical conductivity (mmhos/cm): 0 to 4
Sodium Adsorption Ratio: 0 to 5
Reaction: moderately acid to moderately alkaline

Btkg Horizon:
Hue: 10YR to 5Y
Value: 5 or 6
Chroma: 1 to 4
Texture: clay, silty clay or silty clay loam
Clay content: 33 to 50 percent
Clay films: location on surfaces of peds, contrast faint or distinct
Redox concentrations: amount-common or many, size-fine, contrast-prominent, shades-red, brown or yellow
Redox depletions: amount-none to many, size-medium, contrast-distinct, shades-gray
Identifiable secondary carbonate: amount-few or common, size-fine to coarse, kind-carbonate concretions
Electrical conductivity (mmhos/cm): 0 to 4
Sodium Adsorption Ratio: 1 to 5
Reaction: neutral to moderately alkaline

Btkssg Horizon:
Hue: 10YR to 5Y
Value: 5 or 6
Chroma: 1 or 2
Texture: clay, silty clay or silty clay loam
Clay content: 30 to 50 percent
Clay films: location on surfaces of peds, contrast distinct
Slickensides/Pressure faces: amount-few to common
Redox concentrations: amount-few to common, size-fine to coarse, contrast-prominent, shades-red or brown
Redox depletions: amount-none to few, size-fine, contrast-distinct, shades-gray
Identifiable secondary carbonate: amount-few to common, size-fine to coarse, kind-carbonate concretions
Electrical conductivity (mmhos/cm): 0 to 4
Sodium Adsorption Ratio: 1 to 5
Reaction: neutral to moderately alkaline

COMPETING SERIES: There are no other series in the same family. Similar soils are the Mebane, Midland (LA), Natalbany (LA), and Tensas (LA)
Mebane soils: have a very-fine control section
Midland soils: do not have subhorizons with 3 or more chroma and are poorly drained
Natalbany soils: do not have subhorizons with 3 or more chroma and are poorly drained
Tensas soils: do not have subhorizons with 3 or more chroma

GEOGRAPHIC SETTING:
Parent material: loamy fluviomarine deposits derived from igneous, metamorphic and sedimentary rock
Landscape: flat coastal plains
Landform: abandoned meander scrolls
Slope: 0 to 3 percent
Mean annual soil temperature: 19.9 to 21.7 degrees C (67 to 70 degrees F)
Mean annual air temperature: 19.3 to 20.1 degrees C (67 to 68 degrees F)
Mean annual precipitation: 1499 to 1651 mm (59 to 65 in)
Frost-free period: 240 to 300 days
Elevation: 1.5 to 15 m (5 to 50 ft)

GEOGRAPHICALLY ASSOCIATED SOILS: These are the similar Crowley, Edgerly and Mowata soils.
Crowley soils: have an albic horizon and are on about the same to slightly lower landscape positions.
Edgerly soils: are poorly drained and have a mollic epipedon
Mowata soils: are on lower landscape positions and are poorly drained

DRAINAGE AND PERMEABILITY: Somewhat poorly drained. Permeability is very slow. Runoff is medium on 0 to 1 percent slopes and high on 1 to 3 percent slopes. An apparent water table fluctuates between a depth of 1.5 to 2.5 ft below the surface during the months of December through April.

USE AND VEGETATION: Used mainly for cropland or pasture. Some areas are used for homesites. Native vegetation is dominantly tall grasses and sedges.

DISTRIBUTION AND EXTENT: Gulf Coastal Prairie of Louisiana and possibly southeast Texas (MLRA 150A, LRR T). The series is of large extent.

MLRA SOIL SURVEY REGIONAL OFFICE (MO) RESPONSIBLE: Temple, Texas

SERIES ESTABLISHED: Cameron Parish, Louisiana; 1984.

REMARKS: These soils were formerly included with the Crowley series. Classification changed 7/99 based on Keys to Soil Taxonomy, Eighth Edition, 1998. Also, mineralogy changed from mixed to smectitic based on LSU soil lab data and mineralogy of associated soils.

Diagnostic Horizons and features recognized in this pedon are:
Ochric epipedon: 0 to 25 cm (0 to 10 in) (Ap1 and Ap2 horizons)
Argillic horizon: 25 to 203 cm (10 to 65 in) (Btg1, Btg2, Btkg1, Btkg2, Btkssg1, Btkssg2 horizons)
Aquic moisture regime and episaturation: in upper argillic horizon
Chromic feature: Value of 4 or more in the ochric epipedon (Ap1 an d Ap2 horizons)
Vertic subgroup: linear extensibility more than 6.0 cm in upper 40 inches and slickensides in argillic horizon

ADDITIONAL DATA: LSU lab data on pedons from Vermilion Parish (S84LA-113-002), Cameron Parish (S85LA-023-004), and Acadia Parish (S96LA-001-006).

Taxonomic Version: Keys to Soil Taxonomy, Twelfth Edition, 2014.

National Cooperative Soil Survey
U.S.A.