LOCATION SUNRAY TX+OKEstablished Series
TAXONOMIC CLASS: Fine-silty, mixed, superactive, mesic Calcidic Paleustolls
TYPICAL PEDON: Sunray loam, on a gently sloping plain, 4 percent slope in range. (Colors are for dry soil unless otherwise stated.)
A--0 to 20 cm (0 to 8 inches), brown (7.5YR 4/3) loam, dark brown (7.5YR 3/3) moist; moderate medium subangular blocky structure; slightly hard, friable; many fine and very fine roots; violently effervescent strongly alkaline; clear smooth boundary. (18 to 36 cm thick)
Btk1--20 to 36 cm (8 to 14 inches), brown (7.5YR 5/4) clay loam, brown (7.5YR 4/4) moist; moderate coarse prismatic parting to moderate medium subangular blocky structure; slightly hard, friable; many fine and very fine roots; common worm casts; few faint clay films on ped surfaces; estimated 18 percent calcium carbonate by volume in the form of masses and nodules; violently effervescent; strongly alkaline; gradual wavy boundary. (13 to 30 cm thick)
Btk2--36 to 56 cm (14 to 22 inches), strong brown (7.5YR 5/6) clay loam, strong brown (7.5YR 4/6) moist; moderate coarse prismatic parting to strong medium subangular blocky structure; hard, firm; common fine and very fine roots; few distinct clay films on ped surfaces; estimated 28 percent calcium carbonate by volume in the form of masses and nodules; violently effervescent; strongly alkaline; gradual wavy boundary. (15 to 30 cm thick)
Btk3--56 to 91 (22 to 36 inches), strong brown (7.5YR 5/6) loam, strong brown (7.5YR 4/6) moist; strong coarse prismatic parting to strong medium subangular blocky structure; hard, firm; common fine and very fine roots; many distinct clay films on ped surfaces; estimated 31 percent calcium carbonate by volume in the form of films, filaments, masses, and nodules; violently effervescent; strongly alkaline; gradual wavy boundary. (25 to 50 cm thick)
Btk4--91 to 145 cm (36 to 57 inches), strong brown (7.5YR 5/6) clay loam, strong brown (7.5YR 4/6) moist; strong coarse prismatic parting to strong medium subangular blocky structure; very hard, very firm; few very fine roots; many distinct clay films on ped surfaces; estimated 21 percent calcium carbonate by volume in the form of films, filaments, masses, and nodules; violently effervescent; very strongly alkaline; gradual wavy boundary. (25 to 60 cm thick)
Btk5--145 to 173 cm (57 to 68 inches), strong brown (7.5YR 5/6) clay loam, strong brown (7.5YR 4/6) moist; moderate medium subangular blocky structure; hard, friable; few very fine roots; few distinct clay films on ped surfaces; estimated 12 percent calcium carbonate by volume in the form of masses and nodules; violently effervescent; very strongly alkaline; diffuse irregular boundary. (25 to 50 cm thick)
Btk6--173 to 203 cm (68 to 80 inches), strong brown (7.5YR 5/6) clay loam, strong brown (7.5YR 4/6) moist; moderate medium subangular blocky structure; hard, friable; few very fine roots; few distinct clay films on ped surfaces; estimated 10 percent calcium carbonate by volume in the form of masses and nodules; violently effervescent; very strongly alkaline.
TYPE LOCATION: Hansford County, Texas; from the intersection of State Highway 207 and Farm Road 520 approximately 9.3 kilometers (5.8 miles) southwest of Spearman; 8.5 kilometers (5.3 miles) west on Farm Road 520; 1 kilometer (0.6 mile) north on county road; 322 meters (1056 feet) east in range. Latitude: 36 degrees, 07 minutes, 58.1 seconds N; 101 degrees, 20 minutes, 20.4 seconds W; Hansford Texas USGS quad; NAD 83.
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: 13 to 15 degrees C (55 to 59 degrees F).
Depth to secondary carbonates: 0 to 25 cm (0 to 10 in).
Depth to calcic horizon: 13 to 60 cm (5 to 24 in).
Thickness of the mollic epipedon: 20 to 50 cm (7 to 20 in).
Solum thickness: More than 203 cm (80 in).
Particle-size control section: 18 to 35 percent silicate clay with the sand fraction dominated by very fine sands.
A horizon:
Hue: 7.5YR or 10YR
Value: 4 or 5, 3 or less moist
Chroma: 2 or 3
Texture: loam, clay loam, silty clay loam
Effervescence: strong or violent
Reaction: moderately alkaline or strongly alkaline
Upper Btk horizons:
Hue: 7.5YR to 10YR
Value: 4 to 6, 3 to 5 moist
Chroma: 3 to 6
Texture: loam, clay loam, silty clay loam
Visible secondary calcium carbonate: 10 to 49 percent by volume as films, filaments, masses, nodules, and finely disseminated carbonates.
Effervescence: strong or violent
Reaction: moderately or strongly alkaline
Lower Btk horizons:
Hue: 2.5YR to 7.5YR
Value: 5 to 7, 4 to 6 moist
Chroma: 4 to 6
Texture: clay loam, silty clay loam, sandy clay loam
Visible secondary calcium carbonate: 10 to 49 percent by volume as films, filaments, masses, nodules, and finely disseminated carbonates.
Effervescence: violent
Reaction: strongly alkaline or very strongly alkaline
Btkk horizon (where present):
Hue: 2.5YR to 7.5YR
Value: 7 or 8
Chroma: 1 to 6
Texture: clay loam, silty clay loam, sandy clay loam
Visible secondary calcium carbonate: 10 to 49 percent by volume as films, filaments, masses, nodules, and finely disseminated carbonates.
Effervescence: violent
Reaction: strongly alkaline or very strongly alkaline
COMPETING SERIES: There are no other series in this family. Similar soils include the
Canina,
Capps,
Conlen,
Kerrick,
Mansker,
Oslo,
Plack,
Spurlock,
Texline, and
Vorhees series.
Canina series: have an ochric epipedon.
Capps and Vorhees series: have cambic horizons.
Conlen and Spurlock series: have coarse-loamy particle size control section and carbonatic mineralogy.
Kerrick series: have a petrocalcic horizon between 50 and 100 cm.
Mansker series: have soil temperatures of more than 15 degrees C (59 degrees F) and carbonatic mineralogy.
Oslo series: have a calcic horizon between 60 and 100 cm.
Plack series: have a petrocalcic horizon between 20 and 50 cm.
Texline series: have a fine-loamy particle size control section.
GEOGRAPHIC SETTING:
Parent material: Loamy, calcareous eolian sediments of Pleistocene age.
Landform: eolian plain or draws.
Slopes: 0 to 5 percent
Elevation: 916 to 1,448 meters (3,000 to 4,750 ft)
Mean annual air temperature: 12 to 14 degrees C (54 to 57 degrees F)
Mean annual precipitation: 432 to 559 mm (17 to 22 in)
Frost-free period: 170 to 200 days
Thornthwaite annual P-E Index Values: 25 to 36
GEOGRAPHICALLY ASSOCIATED SOILS:
These are the similar
Capps,
Conlen,
Kerrick,
Oslo,
Plack,
Spurlock, and
Texline series and the
Dallam,
Dalhart,
Darrouzett,
Dumas,
Gruver, and
Sherm series.
Capps and Oslo soils are on slightly lower landscape positions.
Conlen, Kerrick, Plack, Spurlock, and Texline soils are on similar landscape positions.
Dallam, Dalhart, and Dumas soils are on higher landscape positions have calcic horizons at depths of more than 60 cm.
Darrouzett, Gruver, and Sherm soils are on higher landscape positions and have more than 35 percent silicate clay in the particle-size control section.
DRAINAGE AND PERMEABILITY: Well drained and moderate permeability. Runoff is negligible on 0 to 1 percent slopes, very low on 1 to 5 percent slopes.
USE AND VEGETATION: Primarily used for rangeland. Where cultivated, the principal crops are grain sorghum, small grains, and forage crops. Climax vegetation is mainly mid and short grasses and includes blue grama, sideoats grama, and buffalograss, with lesser amounts of vine-mesquite, western wheatgrass, tobosa, silver bluestem, and prairieclover with a light to moderate overstory of catclaw and yucca. This soil has been correlated to the Limey Upland (R-077AY006TX) ecological site in MLRA-77A.
DISTRIBUTION AND EXTENT: Southern High Plains, Northern Part (MLRA 77A in LRR H) of the Texas and Oklahoma panhandles and possibly northeastern New Mexico The series is of moderate extent.
MLRA OFFICE RESPONSIBLE: Temple, Texas
SERIES ESTABLISHED: Sherman County, Texas; 1970.
REMARKS: These soils were formerly included in the Mansker series. Series revised during the MLRA-77 Update Soil Survey; Hansford County, Texas; 2006.
Diagnostic horizons and features recognized in this pedon are:
Mollic epipedon - 0 to 20 cm. (A horizon)
Argillic horizon - 20 to 203 cm. (Btk horizons)
Calcic horizon - 20 to 145 cm. (Btk1, Btk2, Btk3, Btk4 horizons)
ADDITIONAL DATA: NSSL data available on mechanical analysis and mineralogy - Sample numbers: S03TX-195-002 (Hansford County, Texas); S94TX-341-002 (Moore County, Texas).
TAXONOMIC VERSION: Keys to Soil Taxonomy, Tenth Edition, 2006.