LOCATION REHOBETH NMEstablished Series
TAXONOMIC CLASS: Fine, mixed, superactive, mesic Chromic Gypsitorrerts
TYPICAL PEDON: Rehobeth silty clay loam--in rangeland on a convex surface of 1 percent slope at an elevation of 6,710 feet. (Colors are for dry soils unless otherwise noted.)
A--0 to 2 inches; reddish brown (2.5YR 4/3) silty clay loam, reddish brown (2.5YR 4/3) moist; moderate very fine granular structure; soft, very friable, sticky and plastic; few very fine roots; few vertical cracks 0.4 inch wide; gypsum greater than 5.0 percent; SAR 4.3; EC 0.4; carbonates are disseminated; strongly effervescent; moderately alkaline (pH 8.4); abrupt smooth boundary. (1 to 4 inches thick)
Bw--2 to 5 inches; reddish brown (2.5YR 4/3) silty clay loam, reddish brown (2.5YR 4/3) moist; strong very fine granular structure; hard, very firm, moderately sticky and moderately plastic; few very fine roots; common very fine irregular pores; few vertical cracks 0.5 inch wide; gypsum greater than 5.0 percent; SAR 3.1; EC 0.4; carbonates are disseminated; slightly effervescent; moderately alkaline (pH 8.4); abrupt wavy boundary. (0 to 4 inches thick)
Bss--5 to 12 inches; reddish brown (2.5YR 4/3) clay, reddish brown (2.5YR 4/3) moist; strong medium and coarse wedge shaped aggregates; extremely hard, extremely firm, very sticky and very plastic; common very fine and few fine roots; few common very fine and fine irregular pores; many pressure faces; many intersecting slickensides; few vertical cracks 0.5 inch wide; gypsum greater than 5.0 percent; SAR 4.09; EC 0.5; slightly effervescent; moderately alkaline (pH 8.2); abrupt irregular boundary. (7 to 42 inches)
Bssny1--12 to 18 inches; reddish brown (2.5YR 4/3) clay, dark reddish brown (2.5YR 3/3) moist; strong medium and wedge shaped aggregates; extremely hard, extremely firm, very sticky and very plastic; common very fine and few fine roots; few very fine irregular pores; many intersecting slickensides; few vertical cracks; few very fine masses and crystals of gypsum and sodium sulfate; gypsum greater than 5.0 percent; SAR 11.3; EC 0.5; slightly effervescent; moderately alkaline (pH 8.2); abrupt irregular boundary.
Bssny2--18 to 32 inches; reddish brown (2.5YR 5/4) clay, reddish brown (2.5YR 4/4) moist; strong medium and coarse wedge shaped aggregates; very hard, very firm; very sticky and very plastic; few very fine, fine, and medium roots; few very fine irregular pores; common intersecting slickensides; few vertical cracks; many fine and medium masses and crystals of gypsum and sodium sulfate; gypsum greater than 5.0 percent; SAR 12.8; EC 1.6; slightly effervescent; moderately alkaline (pH 8.2); clear wavy boundary. (The combined thickness of the Bssny horizons is 20 to 50 inches)
Bssny3--32 to 80 inches; reddish brown (2.5YR 5/4) clay, reddish brown (2.5YR 4/4) moist; strong coarse wedge shaped aggregates; very hard, very firm, very sticky and very plastic; few very fine roots; few very fine irregular pores; common intersecting slickensides; many masses and crystals of gypsum and sodium sulfate; gypsum 1.3 percent; SAR 14; EC 6.6; slightly effervescent; moderately alkaline (pH 8.2). (20 to 40 inches thick)
TYPE LOCATION: McKinley County, New Mexico; about 2.3 miles north of Ft. Wingate, New Mexico; Church Rock Quadrangle; T. 15 N., R. 16 W.; 108 degrees 32 minutes 11 seconds west longitude, 35 degrees 30 minutes 12 seconds north latitude.
RANGE IN CHARACTERISTICS:
Soil Moisture: Intermittently moist in some part of the soil moisture control section November through April and July through October. The period of maximum precipitation is July through October. The soil is driest during May and June. Ustic aridic moisture regime.
Soil temperature: 48 to 56 degrees F
Particle-size control section: 40 to 55 percent clay
Depth to the gypsic horizon (with sodium sulfate accumulations): 12 to 80 inches with 5 to 10 percent gypsum, gypsum content decreases in the underlying horizon
Calcium Carbonate equivalent: 1 to 5 percent
Reaction: Moderately alkaline
Vertic properties: slight gilgai: microrelief ranges up to 2 inches; cracks: 0.5 to 1 inches in width range from 2 to 30 inches vertically; pressure faces and intersecting slickensides: few to many below 2 inches
Rock fragments: 0 to 1 percent sandstone and siliceous pebbles
A horizon
Value: 4 dry or moist
Chroma: 3 dry or moist
Salinity: EC of 0-2 mmhos/cm
Sodicity: SAR of 2-5
Bw horizon
Salinity: EC of 0-2 mmhos/cm
Sodicity: SAR of 2-5
Bssy horizon
Calcium carbonate equivalent: 1 to 10 percent
Gypsum and sodium sulfate: Few to common clusters of crystals
Percent gypsum: 5 to 10 percent
Salinity: EC of 0-2 mmhos/cm
Sodicity: SAR of 2-5
Bssny horizons
Value: 4 or 5 dry, 3 or 4 moist
Calcium carbonate equivalent: 1 to 10 percent
Percent gypsum: 5 to 10 percent
Salinity: EC of 2-8 mmhos/cm
Sodicity: SAR of 5-14
COMPETING SERIES: This is the Berryhill (NM) series. Berryhill soils have 10YR or 2.5Y Hues.
GEOGRAPHIC SETTING: The Rehobeth soils formed in alluvium and stream alluvium derived from gypsiferous shale and are on flood plains on valley floors. Slopes are 0 to 1 percent. Elevations range from 6600 to 6800 feet. The mean annual temperature is 46 to 54 degrees F., and the mean annual precipitation is 10 to 13 inches. The frost free period is 100 to 140 days.
GEOGRAPHICALLY ASSOCIATED SOILS: These are the Berryhill, Casamero, Penistaja, and Tintero soils on fan terraces; and the Ojocal soils on flood plains. The Casamero soils are shallow to shale. The Penistaja and Tintero soils are fine-loamy. The Ojocal soils lack vertic properties and a gypsic horizon.
DRAINAGE AND PERMEABILITY: Well drained, high runoff, and very slow permeability.
USE AND VEGETATION: This series is used for rangeland. The present vegetation is black greasewood and alkali sacaton.
DISTRIBUTION AND EXTENT: West central New Mexico; MLRA 35, LRR-D. This series is of small extent.
MLRA SOIL SURVEY REGIONAL OFFICE (MO) RESPONSIBLE: Phoenix, Arizona.
SERIES ESTABLISHED: McKinley County Area, New Mexico; McKinley County and Parts of Cibola and San Juan Counties, 2001.
REMARKS: Diagnostic horizons and features recognized in this pedon are:
Ochric epipedon: The zone from 0 to 2 inches. (A horizon)
Gypsic horizon: The zone from 12 to 80 inches. (Bssny1 and Bssny2)
Vertic properties: Gilgai microrelief ranges up to 2 inches. Cracks are 0.5 to 2 inches in width and range 2 to 30 inches vertically or more. Pressure faces and intersecting slickensides are few to many below 2 inches.
Classified according to Soil Taxonomy Second Edition, 1999.
ADDITIONAL DATA:
This pedon had tests run for SAR, calcium carbonate, and percent gypsum by Inter-Mountain Laboratories in Farmington, New Mexico. Electrical conductivities were performed on the field lab EC meter.