LOCATION BELEN                   NM+TX

Established Series
Rev. DSP/CDL/RJA/WWJ
07/2012

BELEN SERIES

The Belen series consists of very deep, well drained soils that formed in clayey alluvium of old oxbow lakes that are underlain by loamy alluvium several feet thick. Slopes are 0 to 1 percent. The mean annual precipitation is about 8 inches, and the mean annual temperature is about 59 degrees F.

TAXONOMIC CLASS: Clayey over loamy, smectitic over mixed, superactive, calcareous, thermic Vertic Torrifluvents

TYPICAL PEDON: Belen clay loam--cultivated. (Colors are for dry soil unless otherwise noted.)

Ap--0 to 7 inches; brown (7.5YR 5/2) clay loam, brown (7.5YR 4/4) moist; weak medium subangular blocky structure; very hard, firm, moderately sticky, moderately plastic; common fine roots; common very fine and few pores; strongly effervescent; strongly alkaline (pH 8.5); abrupt smooth boundary. (0 to 10 inches thick)

C1--7 to 31 inches; reddish gray (5YR 5/2) clay, reddish brown (5YR 4/3) moist; few fine distinct mottles of reddish yellow (7.5YR 6/6) in the lower part; massive with few very weak thin plates; very hard, very firm, very sticky, very plastic; common very fine roots in the upper part; common very fine pores; few intersecting slickensides; strongly effervescent; moderately alkaline (pH 8.4); clear smooth boundary. (14 to 26 inches thick)

2C2--31 to 60 inches; light brown (7.5YR 6/4) fine sandy loam, brown (7.5YR 5/4) moist; common medium faint mottles of reddish yellow (7.5YR 6/6); massive; slightly hard, very friable, common very fine tubular pores; strongly effervescent; strongly alkaline (pH 8.7).

TYPE LOCATION: Valencia County, New Mexico; about 2,800 feet north and 2,000 feet west of headquarters of New Mexico penitentiary farm.

RANGE IN CHARACTERISTICS:

Soil moisture - Intermittently moist in the soil moisture control section during July-August and December-January. Driest during May and June. Typic aridic soil moisture regime.

Soil Temperature: 59 to 72 degrees F.

Reaction: Moderately to very strongly alkaline.

Depth to contrasting layer: 20 to 36 inches.

Calcium carbonate equivalent: Less than 15 percent, carbonates usually disseminated but range to fine soft masses, threads, and thin coatings.

Rock fragments: 5 to 15 percent gravel.

Salinity: nonsaline to strongly saline.

A horizon
Hue: 7.5YR or 10YR
Value: 4 to 6, dry or moist
Chroma: 2 or 3 dry, and 2 through 4 moist
Texture: clay loam, clay

C horizon
Hue: 5YR, 7.5YR, or 10YR
Value: 3 to 6, dry or moist
Chroma: 1 to 4, dry or moist
Texture: silty clay, clay, clay loam
Relict mottles: none in upper part of the C to common in the lower part.
Cracks: 1 to 2 cm. wide to depths of 20 inches or more in most years unless irrigated.

2C horizon
Hue: 7.5YR or 10YR
Value: 5 or 7 dry, 4 or 5 moist
Chroma: 2 to 4, dry or moist
Texture: silt loam to very fine sand with less than 20 percent clay
Relict mottles: few to common

COMPETING SERIES: There are no competing series.

GEOGRAPHIC SETTING: Belen soils are on nearly level flood plains of major streams at elevations of 3,000 to 5,500 feet. Slopes are 0 to 1 percent. The soils formed in clayey alluvium of old oxbow lakes that are underlain by loamy alluvium several feet thick. The climate is semiarid to arid continental. At the type location average annual temperature is 58 to 67 degrees F. and annual precipitation is 8 to 11 inches. Much of the precipitation falls during the summer in heavy thunderstorms of short duration. The Thornthwaite P-E Index is about 14. The frost-free period is 180 to 240 days.

GEOGRAPHICALLY ASSOCIATED SOILS: These are the Agua, Anapra, Armijo, Brazito, Gila, Glendale, and Vinton soils. Agua, Anapra, Brazito, Gila, Glendale, and Vinton soils have texture coarser than clay throughout the control section. Armijo, Brazito, Gila, Glendale, and Vinton soils lack a contrasting horizon in the lower part of the control section.

DRAINAGE AND PERMEABILITY: Well drained; relict mottles indicate that drainage has been restricted in the past. Presently, the water table is deeper than 60 inches. Surface runoff is slow to very slow. Permeability is slow to very slow in the C1 horizon and moderate in the 2C2 horizon.

USE AND VEGETATION: Used for cultivated crops and permanent pasture where irrigated. Alfalfa, small grains, and sorghum are common irrigated crops. The more alkali and saline areas are usually used as unimproved range or pasture. Native vegetation is primarily alkali sacaton, saltgrass, fourwing saltbush, and annuals.

DISTRIBUTION AND EXTENT: Belen soils are in southern New Mexico and are moderately extensive. This soil occurs in LRR-D, MLRA 42.

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

SERIES ESTABLISHED: Valencia County (East Valencia Area), New Mexico, 1970.

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

Ochric epipedon: The zone from 0 to 2 inches (A horizon).

Entisol feature: Lack of diagnostic horizons.

Fluvent feature: Irregular decrease in organic carbon.

Contrasting Particle Size: Absolute difference of more than 25 percent at 31 inches.

Classified according to Soil Taxonomy, Second Edition, 1999; Keys to Soil Taxonomy, Eleventh Edition, 2010

Revised for the correlation of Hudspeth County, Texas (Main Part) and Culberson County, Texas (Main Part); July, 2012, NMS

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National Cooperative Soil Survey
U.S.A.