LOCATION HARJO                   OK+TX

Established Series
Rev. ELC:AMS:JLD
08/2017

HARJO SERIES

The Harjo series consists of deep, poorly drained, very slowly permeable soils. They formed in predominantly clayey alluvium of Holocene age. These nearly level soils are on flood plains in concave positions of the Cross Timbers. Slope ranges from 0 to 1 percent. Mean annual air temperature is about 16.1 degrees C (61 degrees F), and mean annual precipitation is about 889 mm (35 in).

TAXONOMIC CLASS: Fine, mixed, superactive, calcareous, thermic Typic Fluvaquents

TYPICAL PEDON: Harjo clay-rangeland, at an elevation of 259 m (850 ft). (Colors are for moist soil unless otherwise stated.)

A1--0 to 25 cm (0 to 10 in); dark red (2.5YR 3/6) clay; weak medium platy in upper part and weak medium subangular blocky structure in lower part; extremely hard, firm; calcareous; strongly effervescent; moderately alkaline; clear smooth boundary.

A2--25 to 91 cm (10 to 36 in); reddish brown (2.5YR 4/4) clay; few fine faint red (2.5YR 4/6) mottles; moderate coarse subangular blocky structure parting to weak fine blocky; extremely hard, firm; calcareous; strongly effervescent; moderately alkaline; gradual smooth boundary. (Combined thickness of the A horizon is 33 to 150 cm [13 to 60 in])

C--91 to 165 cm (36 to 65 in); red (2.5YR 4/6) clay; massive; extremely hard, firm; few thin strata of dark reddish brown (2.5YR 3/4) and weak red (10R 4/4) clay loam; calcareous; strongly effervescent; moderately alkaline.

TYPE LOCATION: Pottawatomie County, Oklahoma, about 3 miles south and 1 mile west of Maud; about 400 feet west and 1100 feet north of the southeast corner of sec. 8, T. 7 N., R. 5 E.

USGS Topographic Quadrangle: Saint Louis, OK
Latitude: 35 degrees, 23 minutes, 23.789 seconds N
Longitude: 96 degrees, 47 minutes, 35.036 seconds W

Decimal Degrees:
Latitude: 35.09000 degrees
Longitude: -96.79300 degrees
Datum: NAD83

UTM Easting: 701185 m
UTM Northing: 3885245 m
UTM Zone: 14N

RANGE IN CHARACTERISTICS:
Soil thickness: greater than 152 cm (60 in)

Particle-size control section (weighted average):
Clay content: 35 to 60 percent

A1 horizon:
Hue: 2.5YR or 5YR
Value: 3 or 4
Chroma: 4 to 6
Mottles: some pedons have mottles in shades of black
Texture: loam, clay loam, or clay
Effervescence: slight to strong
Reaction: slightly alkaline or moderately alkaline

A2 horizon:
Hue: 2.5YR or 5YR
Value: 4
Chroma: 2 to 6
Mottles: some pedons have mottles in shades of red, brown, gray, or black Texture: clay
Effervescence: strong
Reaction: moderately alkaline

C horizon:
Hue: 2.5YR or 5YR
Value: 3 to 5
Chroma: 2 to 6
Mottles: most pedons have mottles in shades of red or brown
Texture: loam, clay loam, or clay
Stratification: stratified with thin strata of clay to loamy very fine sand
Effervescence: strong
Reaction: moderately alkaline

Buried horizons (where present):
Hue: 2.5YR or 5YR
Value: 2 to 4
Chroma: 1 or 2
Mottles: some pedons have mottles in shades of red, brown, or black
Texture: clay loam, silty clay loam, or silty clay
Effervescence: strong
Reaction: moderately alkaline

COMPETING SERIES: There is no series in the same family. Soils in similar families are the Chastain, Fausse, Hayti, Mhoon, Miller, Tuscumbia, and Yorktown series.
Chastain soils: have kaolinitic mineralogy and are noncalcareous
Fausse and Yorktown soils: have very-fine control sections, smectitic mineralogy, and are noncalcareous
Hayti and Mhoon soils: have fine-silty control sections and are noncalcareous Miller soils: have mollic epipedons
Tuscumbia soils: are noncalcareous, have cambic horizons, and have vertic properties

GEOGRAPHIC SETTING:
Parent material: formed in calcareous clayey and loamy sediments of Holocene age
Landscape: alluvial plains
Landform: flood plains
Slope: 0 to 1 percent
Mean annual precipitation: 762 to 1016 mm (30 to 40 in)
Climate: moist subhumid
Thornthwaite annual P-E indices: 44 to 64
Mean annual air temperature: 15.6 to 16.7 degrees C (60 to 62 degrees F)
Frost-free period: 181 to 240 days
Elevation: 244 to 276 m (800 to 900 ft)

GEOGRAPHICALLY ASSOCIATED SOILS: This is the Gracemont series on higher positions.
Gracemont soils: have a coarse-loamy control section

DRAINAGE AND PERMEABILITY:
Drainage: poorly
Permeability: very slow
Runoff: slow
Ponding: water is on the surface or within 30 cm (1 ft) of the surface from October to June

USE AND VEGETATION: About one-third is tame pasture. The remainder is a mixture of willows, ash, salt cedar, sumpweed, cattails, or is nearly barren of vegetation.

DISTRIBUTION AND EXTENT:
General area: Cross Timbers of Oklahoma
Land Resource Region: H-Central Great Plains Winter Wheat and Range
MLRA 84A-North Cross Timbers
Extent: small

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

SERIES ESTABLISHED: Pottawatomie County, Oklahoma; 1974.

REMARKS:
Diagnostic horizons and features in this pedon are:
Ochric epipedon: 0 to 91 cm (0 to 36 in) (A1, A2 horizons)
Fluvaquentic feature: soils with an aquic moisture regime that are saturated with water at some time of the year within 30 cm (12 in) of the soil surface and have an irregular decrease in organic matter content in the 91 to 165 cm (36 to 65 in) zone (C horizon). The high chroma throughout the soil is related to the red parent material. The requirement for low chroma is waived on the assumption the saturated zone is devoid of oxygen and the red colors remain after citrate-dithionate extraction.

Edited 08/2017 (JAD-JLD) Changed to tabular format. Updated pedon description, range in characteristics, and other sections.

ADDITIONAL DATA: none

TAXONOMIC VERSION: Keys to Soil Taxonomy, Twelfth Edition, 2014

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National Cooperative Soil Survey
U.S.A.