LOCATION PRELO                   NM

Established Series
Rev. PSD/JBC/WWJ
12/2014

PRELO SERIES

The Prelo series consists of deep, moderately well drained soils that formed in fine textured alluvium weathered from shale, siltstone, and consolidated alluvium. Prelo soils are on broad floodplains and alluvial fans and have slopes of 0 to 3 percent. The mean annual precipitation is about 8 to 10 inches and the mean annual air temperature is about 61 degrees F.

TAXONOMIC CLASS: Fine-silty, gypsic, thermic Typic Haplogypsids

TYPICAL PEDON: Prelo silt loam, rangeland. (Colors are for dry soil unless otherwise noted.)

Az--0 to 6 inches (0 to 15 cm); reddish brown (5YR 4/4) silt loam, dark reddish brown (5YR 3/3), moist; 23 percent clay; moderate thick platy over moderate medium subangular blocky structure; moderately hard, firm, very sticky, very plastic; few fine dendritic tubular pores; carbonate and gypsum, finely disseminated throughout; strongly effervescent, 10 percent calcium carbonate equivalent and 3 percent gypsum; neutral, pH 6.9; electrical conductivity 22.0 dS/m (mmhos/cm); strongly saline; gradual smooth boundary.

Byz1--6 to 30 inches (15 to 76 cm); reddish brown (5YR 4/4) gypsiferous silty clay loam, dark reddish brown (5YR 3/4), moist; 28 percent clay; moderate medium subangular blocky structure; slightly hard, friable, very sticky, very plastic; few fine dendritic tubular pores; carbonate, finely disseminated and common medium irregular gypsum crystals throughout; strongly effervescent, 9 percent calcium carbonate equivalent and 24 percent gypsum; slightly alkaline, pH 7.4; electrical conductivity 23.0 dS/m (mmhos/cm); strongly saline; gradual smooth boundary.

Byz2--30 to 50 inches (76 to 127 cm); yellowish red (5YR 4/6) gypsiferous silty clay loam, dark reddish brown (5YR 3/4), moist; 31 percent clay; moderate medium subangular blocky structure; slightly hard, friable, very sticky, very plastic; few fine dendritic tubular pores; carbonate, finely disseminated and common medium irregular gypsum crystals throughout; strongly effervescent, 11 percent calcium carbonate equivalent and 18 percent gypsum; slightly alkaline, pH 7.4; electrical conductivity 20.0 dS/m (mmhos/cm); strongly saline; gradual smooth boundary.

Byz3--50 to 60 inches (127 to 152 cm); yellowish red (5YR 5/6) clay loam, yellowish red (5YR 4/6), moist; 28 percent clay; moderate medium subangular blocky structure; slightly hard, friable, moderately sticky, moderately plastic; carbonate, finely disseminated and common medium irregular gypsum crystals, throughout; strongly effervescent, 6 percent calcium carbonate equivalent and 14 percent gypsum; slightly alkaline, pH 7.6; electrical conductivity 21.0 dS/m (mmhos/cm); strongly saline.

TYPE LOCATION: Otero County, New Mexico; 3.15 miles west of intersection on US Highway 54-70 and the La Luz exit, County Road 83, and 50 feet north of the road; corner of SE1/4 SW1/4 section 4, T.16S., R.10E.

RANGE IN CHARACTERISTICS:

Soil moisture: Typic aridic moisture regime.

Gypsum: 3 to 5 percent (B horizon); 5 to 20 percent (C horizon)

Reaction: slightly alkaline to moderately alkaline

A horizon
Hue: 5YR or 7.5YR
Value: 3 through 5 dry, 3 or 4 moist
Chroma: 3 or 4 moist or dry
Texture: silt loam or silty clay loam but ranges to fine sandy loam or very fine sandy loam

B horizon
Hue: 5YR or 7.5YR
Value: 3 through 5 dry, 3 or 4 moist
Chroma: 4 dry and 3 or 4 moist
Texture: silty clay loam or silt loam; the lower part of the B horizon is clay loam in some pedons
Clay content: 25 to 35 percent.

C horizon
Hue: 5YR or 7.5YR
Value: 3 through 6 dry, 3 or 4 moist
Chroma: 4 dry and 3 or 4 moist
Texture: silty clay loam but in some pedons is clay loam in some parts
Gypsum: occurs as distinct crystals in some pedons. Gypsum content increases with depth; however, no gypsum beds were observed at depths greater than 90 inches.

COMPETING SERIES: These are the Mercey (CA), Mimbres (NM), and Russler (NM) series. Mercey soils are in the Central California Coast Range (MLRA 15) receive mostly winter precipitation and are usually dry from April through November. Mimbres soils lack gypsum within the pedon. Reakor soils have a calcic horizon. Russler soils have a paralithic contact at depths of less than 40 inches.

GEOGRAPHIC SETTING: Prelo soils are on broad floodplains and alluvial toe slopes of pediments that terminate on basin floors. Slopes are 0 to 3 percent. Elevations range from 4,000 to 4,800 feet. The soils formed in moderately fine textured calcareous alluvial deposits weathered primarily from the Permian redbeds in the mountain footslopes. The soils are in warm, semiarid continental climate with an annual precipitation of 8 to 10 inches. The mean annual air temperature is 61 degrees F. The frost free season is about 190 to 210 days.

GEOGRAPHICALLY ASSOCIATED SOILS: These are the Alamogordo, Emot, Ogral and Reeves soils and the competing Largo and Tome soils. Alamogordo soils have gypsic horizons. Emot and Ogral soils have skeletal control sections. Reeves soils have calcic horizons.

DRAINAGE AND PERMEABILITY: Well drained; moderate runoff; moderately slow permeability.

USE AND VEGETATION: The soils are used for irrigated cropland, livestock grazing, wildlife habitat, and urbanization. Native vegetation is mainly alkali sacaton, black grama, vine mesquite, burrograss, creosotebush, mesquite, and tobosa.

DISTRIBUTION AND EXTENT: Otero and Eddy Counties, New Mexico. The series is moderately extensive. MLRA 42.

MLRA SOIL SURVEY REGIONAL OFFICE (MO) RESPONSIBLE: Phoenix, Arizona

SERIES ESTABLISHED: Otero County, New Mexico, 1976.

REMARKS: Diagnostic horizons and features recognized in this pedon are:

Ochric epipedon - The zone from 0 to 4 inches (A horizon)

Cambic horizon - The zone from 4 to 32 inches (Bw, By1, By2 horizons)

Classified according to Soil Taxonomy Second Edition, 1999

ADDITIONAL DATA: NSSL number S93NM 035 003 supports the classification.
The characterization data from Sample S74NM35-7-(1 to 10) shows the epipedon is higher in organic carbon than expected.

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National Cooperative Soil Survey
U.S.A.