LOCATION ZELLA OK+KSEstablished Series
TAXONOMIC CLASS: Fine, smectitic, mesic Torrertic Argiustolls
TYPICAL PEDON: Zella silty clay loam, on a nearly level plain, 0.5 percent slope in cropland, at an elevation of about 3,000 feet. (Colors are for dry soil unless otherwise stated.)
Ap1--0 to 4 inches; brown (10YR 4/3) silty clay loam, dark brown (10YR 3/3) moist; weak fine granular structure; hard, friable; common fine roots; few 30 cm deep trans-horizon cracks extend through the horizon; slightly alkaline; abrupt smooth boundary.
Ap2--4 to 7 inches; dark grayish brown (10YR 4/2) silty clay, very dark grayish brown (10YR 3/2) moist; moderate medium angular blocky structure; extremely hard, firm; common medium roots; few fine tubular pores; neutral; abrupt smooth boundary. (combined thickness of Ap horizons 5 to 12 inches thick)
Bt1--7 to 13 inches; dark grayish brown (10YR 4/2) silty clay, very dark grayish brown (10YR 3/2) moist; moderate medium prismatic structure parting to moderate medium angular blocky; extremely hard, very firm; few fine and medium roots in cracks; many distinct clay films on vertical ped surfaces; common continuous cracks up to 2 cm wide; moderately alkaline; clear smooth boundary. (5 to 10 inches thick)
Bt2--13 to 19 inches; brown (10YR 5/3) silty clay loam, brown (10YR 4/3) moist; moderate medium prismatic structure parting to moderate medium angular blocky; extremely hard, very firm; few fine roots; many distinct clay films on vertical ped surfaces; common continuous cracks up to 2 cm wide; slightly effervescent; moderately alkaline; clear smooth boundary. (5 to 10 inches thick)
Btk1--19 to 25 inches; brown (10YR 5/3) silty clay loam, brown (10YR 4/3) moist; moderate medium prismatic structure parting to moderate medium angular blocky; extremely hard, extremely firm; few fine roots; many distinct clay films on vertical ped surfaces; about 3 percent visible calcium carbonate in the form of threads and masses; strongly effervescent; moderately alkaline; gradual smooth boundary. (5 to 10 inches thick)
Btk2--25 to 38 inches; pale brown (10YR 6/3) silty clay loam, brown (10YR 5/3) moist; moderate medium prismatic structure parting to moderate medium angular blocky; hard, firm; many distinct clay films on verticalped surfaces; about 8 percent visible calcium carbonate in the form of threads and masses; violently effervescent; moderately alkaline; gradual wavy boundary. (8 to 15 inches thick)
Bk--38 to 53 inches; very pale brown (10YR 7/3) silty clay loam, pale brown (10YR 6/3) moist; weak medium prismatic structure parting to weak fine subangular blocky; slightly hard, friable; about 3 percent visible calcium carbonate in the form of threads and masses; violently effervescent; strongly alkaline; gradual wavy boundary. (8 to 20 inches thick)
2Btk1--53 to 63 inches; light brown (7.5YR 6/4) silt loam, brown (7.5YR 5/4) moist; weak medium prismatic structure parting to weak fine subangular blocky; slightly hard, firm; few fine and very fine tubular pores; many distinct clay films on ped surfaces; about 2 percent visible calcium carbonate in the form of threads and concretions; moderately effervescent; slightly alkaline; gradual wavy boundary. (8 to 15 inches thick)
2Btk2--63 to 80 inches; brown (7.5YR 5/4) loam, brown (7.5YR 4/4) moist; weak medium prismatic structure parting to weak fine subangular blocky; slightly hard, firm; few fine and very fine tubular pores; many distinct clay films on ped surfaces; about 2 percent visible calcium carbonate in the form of threads and concretions; moderately effervescent; slightly alkaline.
TYPE LOCATION: Texas County, Oklahoma; from the intersection of U.S. Highway 64 and State Highway 94 in Hooker, 5.75 miles south on State Highway 94, 2 miles east on county road, 1,000 feet south on county road, 200 feet east in cropland; 1,000 feet south and 200 feet east of the northeast corner, sec. 31, T. 4 N., R. 18 E; Latitude: 36 degrees, 46 minutes, 24 seconds N; Longitude: 101 degrees, 10 minutes, 03 seconds W; Hooker, Oklahoma, USGS quad; NAD 27.
RANGE IN CHARACTERISTICS:
Soil moisture: An ustic moisture regime bordering on aridic. The soil moisture control section is dry in some or all parts for more than 180 but less than 205 days, cumulative, in normal years. July through August and December through February are the driest months. These soils are intermittently moist in September through November and March through June.
Mean annual soil temperature: 57 to 59 degrees F.
Thickness of the mollic epipedon: 9 to 20 inches
Depth to secondary calcium carbonate: 10 to 24 inches
Depth to calcic horizon: greater than 80 inches.
Solum thickness: more than 80 inches.
Particle-size control section: 35 to 42 percent silicate clay.
Note: a clay decrease of more than 20 percent (relative) from the maximum clay content occurs within 40 inches and the matrix has chroma of 4 or less.
A horizon:
Hue: 10YR
Value: 3 or 4 and 2 or 3 moist
Chroma: 2 or 3
Texture: loam, silt loam, silty clay loam or silty clay
Effervescence: none
Reaction: neutral or slightly alkaline
Bt horizon:
Hue: 10YR
Value: 4 or 5 and 3 or 4 moist
Chroma: 2 or 3
Texture: silty clay loam, silty clay, clay loam, or clay
Effervescence: none or slight
Reaction: slightly or moderately alkaline
Btk horizon:
Hue:10YR
Value: 5 to 7 and 4 to 6 moist
Chroma: 2 or 3
Texture: silt loam, silty clay loam, or clay loam
Effervescence: strong or violent
Reaction: moderately or strongly alkaline
Bk horizon:
Hue: 10YR
Value: 5 to 7 and 4 to 6 moist
Chroma: 3 or 4
Texture: silt loam, silty clay loam, loam, or clay loam
Effervescence: strong or violent
Reaction: moderately or strongly alkaline
2Btk horizon:
Hue: 7.5YR or 10YR
Value: 5 to 7 and 4 to 6 moist
Chroma: 3 or 4
Texture: silt loam, silty clay loam, loam, or clay loam
Effervescence: strong or violent
Reaction: slightly to strongly alkaline
COMPETING SERIES: These are the Denver,
Englewood,
Kutch, Perryton, and
Pleasant series. Similar soils include the Belfon, Forgan, Hugoton,
Richfield, and
Sherm series.
Denver, Englewood, Kutch, and Pleasant series: have mean annual temperature less than 13 degrees C. In addition Englewood series have a mollic epipedon more than 20 inches thick. Also Kutch series are moderately deep to a paralithic contact.
Perryton series: have a calcic horizon.
Belfon and Forgan: have a fine-loamy particle-size control section.
Darrouzett: have mixed mineralogy and visible secondary calcium carbonate generally occurs deeper in the solum.
Hugoton: have a fine-silty particle-size control section.
Richfield: have linear extensibility less than 6.0 cm between the soil surface and 40 inches and lower mean annual temperature.
Sherm: have a calcic horizon within 60 inches and the clay content does not decrease by 20 percent (relative) from maximum clay within 60 inches.
GEOGRAPHIC SETTING:
Parent material: loamy, eolian loess deposits of Holocene age.
Landform: nearly level plain.
Slopes: 0 to 1 percent
Elevation: 2,900 to 3,700 feet.
Mean annual air temperature: 55 to 57 degrees F.
Mean annual precipitation: 16 to 21 inches.
Frost-free period: 162 to 203 days.
Thornthwaite annual P-E Index Values: 25 to 34.
GEOGRAPHICALLY ASSOCIATED SOILS: These include the Belfon, Bigbow,
Canina, Dalhart, Forgan, Hugoton, and
Vorhees soils.
Belfon soils are on nearly level landscape positions similar to Zella soils.
Bigbow, Canina, Forgan, and Hugoton soils are on nearly level to very gently sloping plains, low hills, and ridges.
Dalhart and Vorhees soils are on very gently sloping to gently sloping plains, low hills, and ridges.
DRAINAGE AND PERMEABILITY: Well drained. Moderately slow permeability. Runoff is negligible on 0 to 1 percent slopes.
USE AND VEGETATION: Mainly cultivated to corn, winter wheat, and grain sorghum. A considerable acreage is irrigated. Climax vegetation is dominantly short grasses with a few midgrasses and includes blue grama and buffalograss, with lesser amounts of vine-mesquite, western wheatgrass, sideoats grama, silver bluestem, wild alfalfa, and prairie clover. This soil has been correlated to the Hardland (R077AY040OK) and Loamy Upland (R077XY015KS) range site in MLRA-77A.
DISTRIBUTION AND EXTENT: Southern High Plains, Northern Part (MLRA 77A in LRR H) of Southwest Kansas and the Oklahoma Panhandle. The series is of moderate extent.
MLRA SOIL SURVEY REGIONAL OFFICE (MO) RESPONSIBLE: Temple, Texas
SERIES ESTABLISHED: MLRA-77 update of Stevens County, Kansas; 2005.
REMARKS: These soils were previously included in the Richfield series.
Diagnostic horizons and features recognized in this pedon are:
Mollic epipedon: 0 to 16 inches (Ap1, Ap2, and Bt1 horizons)
Argillic horizon: 7 to 38 inches (Bt1, Bt2, Btk1, and Btk2 horizons)
Cambic horizon: 38 to 53 inches (Bk horizon)
Lithologic discontinuity: 53 to 80 inches (2Btk1 & 2Btk2)
Torrertic properties - cracks within 50 inches of the mineral soil surface for some time during normal years and a linear extensibility of 6.0 cm or more between the surface and a depth of 40 inches.
ADDITIONAL DATA: National Soil Survey Laboratory - S84OK-139-005, S92OK-139-002, S92OK-139-003 (Texas County, Oklahoma); 92KS-129-001 (Morton County, Kansas).
TAXONOMIC VERSION: Keys to Soil Taxonomy, Tenth Edition, 2006.