LOCATION MELADO TX
Established Series
DWM/JAC
10/2012
MELADO SERIES
The Melado series consists of very deep, well drained soils that formed in clayey alluvium. Melado soils are on alluvial flats of the Presidio Bolson. Slopes range from 0 to 12 percent. The mean annual precipitation is about 10 inches and the mean annual air temperature is about 72 degrees F.
TAXONOMIC CLASS: Fine, smectitic, hyperthermic Sodic Ustic Haplocambids
TYPICAL PEDON: Melado silty clay, on a southwest facing, 1.0 percent slope in rangeland. (Colors are for dry soil unless otherwise stated.)
An--0 to 4 inches; yellowish brown (10YR 5/4) silty clay, brown (10YR 5/3) moist; weak medium platy structure parting to weak medium subangular blocky; hard, very firm, very sticky and very plastic; strong effervescence; moderately alkaline; gradual smooth boundary. (2 to 5 inches thick)
Bnyz1--4 to 10 inches; brown (10YR 5/3) silty clay, brown (10YR 4/3) moist; weak medium platy and weak coarse prismatic structure parting to weak fine and medium subangular blocky; hard, very firm, very sticky and very plastic; 1 percent gypsum crystals; 1 percent fine threadlike white (10YR 8/1) salt masses; strong effervescence; moderately alkaline; gradual smooth boundary.
Bnyz2--10 to 22 inches; brown (10YR 5/3) silty clay, brown (10YR 4/3) moist; weak coarse prismatic structure parting to weak fine subangular blocky; hard, very firm, very sticky and very plastic; 6 percent gypsum crystals; 5 percent fine threadlike white (10YR 8/1) salt masses; strong effervescence; moderately alkaline; gradual smooth boundary.
Bnyz3--22 to 35 inches; brown (10YR 5/3) silty clay, brown (10YR 4/3) moist; weak coarse prismatic structure parting to weak coarse and medium subangular blocky; hard, very firm, very sticky and very plastic; 5 percent gypsum crystals; 2 percent fine threadlike white (10YR 8/1) salt masses; strong effervescence; moderately alkaline; gradual smooth boundary.
Bnyz4--35 to 44 inches; brown (10YR 5/3) silty clay, brown (10YR 4/3), moist; weak coarse prismatic structure parting to weak medium subangular blocky; hard, very firm; very sticky and very plastic; 4 percent gypsum crystals; 3 percent fine threadlike white (10YR 8/1) salt crystals; strong effervescence; moderately alkaline; gradual smooth boundary. (Combined thickness of the Byz horizon is 14 to 79 inches)
BCnyz--44 to 61 inches; light yellowish brown (10YR 6/4) clay loam, yellowish brown (10YR 5/4), moist; weak medium subangular blocky structure; hard, firm, moderately sticky and moderately plastic; 3 percent gypsum crystals; 2 percent fine threadlike white (10YR 8/1) salt masses; common thin bedding planes; strong effervescence; strongly alkaline; clear wavy boundary. (7 to 21 inches thick)
Cnyz--61 to 87 inches; brown (10YR 5/3) clay, brown (10YR 4/3) moist; moderate medium subangular blocky structure; hard, very firm, very sticky and very plastic; 5 percent fine irregular white (10YR 8/1) gypsum masses; 1 percent fine irregular white (10YR 8/1) gypsum crystals; common thin bedding planes; strong effervescence; strongly alkaline.
TYPE LOCATION: Presidio County, TX; in Presidio, from the junction of U.S. Highway 67 and FM 170 north of Presidio, 9.6 miles northwest on FM 170 to unpaved ranch road; 1.3 miles northeast on unpaved ranch road; 600 feet north in rangeland. USGS Quadrangle: Arroyo Melado, Texas. Latitude: 29 degrees, 40 minutes, 19.19 seconds North, Longitude: 104 degrees, 28 minutes, 49.27 seconds West; NAD83. UTM coordinates: Easting 550283 meters, Northing 3282554 meters; Zone 13.
RANGE IN CHARACTERISTICS:
Soil Moisture: An Ustic aridic soil moisture regime.
Mean annual soil temperature: 72 to 83 degrees F
Particle-size control section (weighted average)
Clay content: 35 to 50 percent
Rock fragments: 0 to 5 percent
An horizon
Hue: 7.5YR, 10YR
Value: 4 to 6 dry, 4 to 5 moist
Chroma: 3 to 4, dry or moist
Texture: silt loam, silty clay loam, silty clay, clay
Clay content: 25 to 45 percent
Rock fragments: 0 to 5 percent
Visible gypsum: 0 to 5 percent
Salt accumulations: 0 to 1 percent, a few areas will have heavy salt crust accumulations on the surface.
Salinity: 0 to 25 dS/m
Sodicity: 0 to 13 SAR
Effervescence: slight to violent
Reaction: moderately alkaline
Bnyz horizon
Hue: 7.5YR, 10YR
Value: 4 to 7 dry, 4 to 5 moist
Chroma: 3 to 4, dry or moist
Texture: silty clay loam, silty clay, clay
Clay content: 35 to 50 percent
Rock fragments: 0 to 5 percent
Visible gypsum: 0 to 6 percent
Salt accumulations: 1 to 5 percent
Salinity: 4 to 26 dS/m
Sodicity: 13 to 30 SAR
Effervescence: slight to violent
Reaction: moderately alkaline
BCnyz or CBnyz horizon (where present)
Hue: 7.5YR, 10YR
Value: 5 to 6 dry, 4 to 5 moist
Chroma: 3 to 4, dry or moist
Texture: clay loam, silty clay, clay
Clay content: 35 to 40 percent
Rock fragments: 0 to 5 percent
Visible gypsum: 1 to 18 percent
Salt accumulations: 1 to 5 percent
Salinity: 8 to 20 dS/m
Salinity: 13 to 40 SAR
Effervescence: slight to strong
Reaction: moderately or strongly alkaline
Cnyz or 2Cny horizons
Hue: 7.5YR, 10YR
Value: 5 to 6 dry, 4 to 5 moist
Chroma: 3 to 4, dry or moist
Texture: clay loam, silty clay, clay
Clay content: 30 to 45 percent
Rock fragments: 0 to 33 percent
Visible gypsum: 1 to 6 percent
Salt accumulations: 0 to 2 percent
Salinity: 8 to 20 dS/m
Sodicity: 13 to 60 SAR
Effervescence: slight to strong
Reaction: moderately or strongly alkaline
COMPETING SERIES: There are no competing series in the same family.
GEOGRAPHIC SETTING: Melado soils are on alluvial flats of the Presidio Bolson at elevations of 1,800 to 3,995 feet. Slope ranges from 0 to 12 percent. These soils formed in clayey alluvium. Mean annual precipitation ranges from 10 to 13 inches. Most precipitation occurs as high intensity rain during afternoon thunderstorms from June to September. The mean annual air temperature is 68 to 72 degrees F. The frost-free period is 240 to 280 days.
GEOGRAPHICALLY ASSOCIATED SOILS: These are the
Changas (T-TX) series,
Corazones (TX), and
Pantera (TX) series. Changas soils have densic bedrock within 20 inches of the surface and occur on fan remnants. Corazones soils have a calcic horizon and occur on fan remnants. Pantera soils are in a sandy-skeletal textural family and occur in drainageways.
DRAINAGE AND PERMEABILITY: Well drained. Permeability is slow. Runoff is medium on slopes less than 1 percent, high on 1 to 5 percent, and very high on 5 to 12 percent.
USE AND VEGETATION: Used for livestock grazing, wildlife habitat, and recreation. Desert Shrubland vegetative zone. Native vegetation consists of fourwing saltbush, mound saltbush, and alkali sacaton.
DISTRIBUTION AND EXTENT: West Texas. MLRA 42. The series is of minor extent.
MLRA SOIL SURVEY REGIONAL OFFICE (MO) RESPONSIBLE: Phoenix, Arizona
SERIES ESTABLISHED: Presidio County, Texas, 2012. The name is from an arroyo.
REMARKS: Diagnostic horizons and features recognized in this pedon are:
Particle-size control section - the zone from 10 to 40 inches (Byz2, Byz3, Byz4 horizons)
Ochric epipedon - the zone from 0 to 4 inches (A horizon)
Cambic horizon - the zone from 4 to 44 inches (Byz1, Byz2, Byz3, Byz4 horizons)
Classified according to Soil Taxonomy, Second Edition, 1999; Keys to Soil Taxonomy, Eleventh Edition, 2010
Revised for the correlation of Presidio County, Texas ; Oct, 2012, WWJ
ADDITIONAL DATA: Data from TAMU Soil Characterization Lab(#S04TX377-002) is available for this type location pedon S04-TX377-326.
National Cooperative Soil Survey
U.S.A.