LOCATION DELNORTE                TX+AZ NM

Established Series
Rev. ERB/DGS
11/2014

DELNORTE SERIES

The Delnorte series consists of soils that are very shallow and shallow to a petrocalcic horizon. They are well drained soils that are, moderately rapidly permeable above and below a very slowly permeable petrocalcic horizon. They formed in calcareous loamy materials containing igneous gravel. These soils are on nearly level hilly uplands, fan piedmonts, and fan remnants. Slope ranges from 0 to 30 percent.

TAXONOMIC CLASS: Loamy-skeletal, mixed, superactive, thermic, shallow Calcic Petrocalcids

TYPICAL PEDON: Delnorte very gravelly loam--rangeland. (Colors are for dry conditions unless otherwise noted.)

A--0 to 8 inches; pinkish gray (7.5YR 6/2) very gravelly loam, brown (7.5YR 4/3) moist; weak granular structure; slightly hard, friable; 55 percent angular and subrounded igneous gravel that are coated with calcium carbonate; coarse fragments are mostly less than 2 inches in diameter; few rounded cobbles; few fine roots; strongly effervescent; moderately alkaline; abrupt wavy boundary (4 to 14 inches thick)

Bkk--8 to 12 inches; pinkish gray (7.5YR 6/2) extremely gravelly loam, brown (7.5YR 5/2) moist; weak fine and medium granular and subangular blocky structure; very hard, friable; many fine roots; 80 percent moderately to strongly cemented calcium carbonate; 75 percent angular and subrounded igneous gravel that are coated with calcium carbonates; violently effervescent; moderately alkaline; abrupt wavy boundary (2 to 6 inches thick)

Bkkm--12 to 20 inches; very pale brown (10YR 8/2) indurated caliche; upper 5 inches is laminar, containing few brownish bands, few fractures; in the lower part of the caliche is massive and is less hard with depth and contains imbedded igneous gravel (7 to 30 inches thick)

BCk--20 to 80 inches; very pale brown (10YR 7/3) extremely gravelly fine sand, pale brown (10YR 6/3) moist; single grain; loose; 80 percent subrounded limestone and igneous gravel mostly less than 2 inches in diameter, that are coated with calcium carbonate, strongly effervescent, moderately alkaline.

TYPE LOCATION: El Paso County, Texas; From the junction of Interstate 10 and Trans-mountain Road at Canutillo Texas; 2.4 miles east on Trans-mountain Road 100 feet south in range (Latitude: 31 degrees, 54 minutes, 18 seconds North; Longitude: 106 degrees, 32 minutes, 20 seconds West).

RANGE IN CHARACTERISTICS:

Soil Moisture: The moisture control section is usually dry in all parts more than three-fourths of the time that the soil temperature exceeds 41 degrees F. Typic aridic soil moisture regime.

Mean annual soil temperature: 63 to 72 degrees F.

Depth to petrocalcic horizon: 5 to 20 inches

Petrocalcic thickness: 7 to 30 inches

Clay content: 5 to 25 percent

Coarse fragments: 35 to 85 percent

Calcium carbonate equivalent: 5 to 40 percent

Reaction: moderately alkaline (pH 7.9 to 8.4)

A horizon
Hue: 7.5YR, 10YR
Value: 3 to 6 dry, 3 to 5 moist
Chroma: 2 to 4, dry or moist
Clay content: 5 to 25 percent
Coarse fragments content: mostly granite and other igneous fragments, 25 to 75 percent angular gravel and cobble size

Bk and Bkk horizons
Hue: 7.5YR, 10YR
Value: 4 to 8 dry, 3 to 7 moist
Chroma: 2 to 4, dry or moist
Clay content range: 5 to 25 percent
Texture: loam, fine sandy loam, sandy loam, coarse sandy loam
Coarse fragment content: mostly granite and other igneous fragments, 25 to 85 percent

Bkkm horizon
Contains indurated or strongly cemented hardpan plates. The upper 0.5 to 2 inches is laminar in some pedons. The upper part is indurated or strongly cemented grading to weakly cemented in the lower part.
Thickness: The petrocalcic horizon is 7 to 30 inches thick

BCk horizon
Hue: 7.5YR, 10YR
Value: 5 to 8 dry, 4 to 7 moist
Chroma: 2 or 3, dry or moist
Texture: sandy loam, loamy fine sand, fine sand
Coarse fragment content: igneous fragments and strongly cemented caliche fragments, 35 to 85 percent, gravel size
Clay content: 5 to 18 percent

COMPETING SERIES: These are the Kimrose (AZ), Missile (NM), Pedregosa (AZ), Winkel (UT), and Yurm (NV) series. Missile, Kimrose, and Pedregosa soils are in an ustic aridic moisture regime. Winkel soils have bedrock at 20 to 40 inches. Winkel and Yurm are located in the Mohave Desert and are moist in the soil moisture control section for less than 20 days cumulative between July and September.

GEOGRAPHIC SETTING: Delnorte soils formed in calcareous loamy alluvium. They are on hilly uplands, fan piedmonts, and fan remnants. Slope ranges from 0 to 45 percent. The elevation is 2,000 to 4,200 feet. The mean annual precipitation is 7 to 12 inches. Precipitation falls mostly during the months of July through September. The driest months are March and April. The mean annual air temperature is 60 to 70 degrees F. The frost-free period is 190 to 280 days.

GEOGRAPHICALLY ASSOCIATED SOILS: These are the Brewster, Canutio, Crotalus, and Sotol series. Brewster soils are very shallow and shallow over granite or rhyolite and are on hills and mountains. Canutio soils have no diagnostic horizon other than an ochric epipedon and are on fan piedmonts. Crotalus soils are very deep and are on mountain flanks and bases on higher positions. Sotol soils are moderately deep to monzonite and are on mountain flanks and bases on higher positions.

DRAINAGE AND PERMEABILITY: Well drained to excessively drained. Runoff is high on slopes less than 1 percent and very high on slopes greater than 1 percent. Permeability is moderately rapid above and below the very slowly permeable petrocalcic horizon.

USE AND VEGETATION: Used for livestock grazing and urban development. Rangeland is of low carrying capacity. Desert shrub and desert grassland with dominant vegetation of creosotebush and lechuguilla, scattered ocotillo; grasses are chino grama and fluffgrass.

DISTRIBUTION AND EXTENT: West Texas, Southern New Mexico, and Arizona (MLRAs 42, 41, and 40). The series is of moderate extent.

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

SERIES ESTABLISHED: Ward County, Texas; 1969.

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

Ochric epipedon - the zone from 0 to 8 inches (A horizon)

Calcic horizon - the zone from 0 to 12 inches (A and Bk horizons)

Petrocalcic horizon - the zone from 12 to 20 inches (Bkm horizon)

Classified according to Soil Taxonomy Second Edition, 1999; Keys to Soil Taxonomy, Twelfth Edition, 2014.

Updated competing series section 3/17/2008, CEM

Revised for the correlation of AZ661, 12/2008, WWJ

Revised for the correlation of Graham County, AZ, Southwestern Part; March, 2011, WWJ

Revised for the correlation of White Sands Missile Range, New Mexico; October, 2014, NMS

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National Cooperative Soil Survey
U.S.A.