LOCATION NATIONS                 TX+NM

Established Series
Rev: DGS/RLB
07/2012

NATIONS SERIES

The Nations series consists of moderately deep and well drained soils formed from recent eolian material and sandy and loamy sediments. Permeability is moderately slow above the very slowly permeable petrocalcic horizon and rapid below the petrocalcic horizon. A cemented pan at about 25 inches underlies these soils. These soils are on fan remnants and wide alluvial flats on basins floors between mountain ranges. Slope ranges from 0 to 3 percent. Mean annual precipitation is about 9 inches and mean annual temperature is about 64 degrees F.

TAXONOMIC CLASS: Coarse-loamy, mixed, superactive, thermic Typic Petrocalcids

TYPICAL PEDON: Nations loamy fine sand--rangeland. (Colors are for dry soil unless otherwise stated.)

A--0 to 5 inches; reddish brown (5YR 5/4), crushed, loamy fine sand, reddish brown (5YR 4/4), crushed, moist; single grain; common very fine roots throughout; noneffervescent throughout (HCl, 1 normal); moderately alkaline; abrupt smooth boundary 4 to 8 inches thick)

2Bw1--5 to 16 inches; strong brown (7.5YR 5/6), crushed, fine sandy loam, strong brown (7.5YR 4/6), crushed, moist; massive; common very fine roots throughout; common medium rounded carbonate nodules throughout; strongly effervescent throughout (HCl, 1 normal); moderately alkaline; clear smooth boundary.

2Bw2--16 to 25 inches; light brown (7.5YR 6/4), crushed, fine sandy loam, brown (7.5YR 5/4), crushed, moist; massive; common medium roots throughout; common medium rounded carbonate nodules throughout; strongly effervescent throughout (HCl, 1 normal); moderately alkaline; abrupt smooth boundary. (Combined thickness of the 2Bw horizons is 16 to 32 inches.)

3Bkkm--25 to 36 inches; white (7.5YR 8/1), broken face, white (7.5YR 8/1), broken face, moist; indurated by carbonates; violently effervescent throughout (HCl, 1 normal); gradual wavy boundary. (4 to 15 inches thick)

3Bk--36 to 63 inches; white (7.5YR 8/1), broken face, loamy sand, pink (7.5YR 8/3), broken face, moist; massive; violently effervescent throughout (HCl, 1 normal); moderately alkaline; clear smooth boundary.

4Btkb--63 to 75 inches; reddish yellow (5YR 6/6), crushed, loamy sand, yellowish red (5YR 4/6), crushed, moist; strong coarse prismatic structure; rigid; few distinct patchy clay films on faces of peds and few prominent continuous carbonate coats in root channels and/or pores; common fine platelike iron-manganese concretions throughout; slightly effervescent throughout (HCl, 1 normal); moderately alkaline; clear smooth boundary. (0 to 15 inches thick)

5C--75 to 80 inches; light reddish brown (5YR 6/4), crushed, loamy fine sand, reddish brown (5YR 5/4), crushed, moist; massive; strongly effervescent throughout (HCl, 1 normal); moderately alkaline.

TYPE LOCATION: El Paso County, Texas; approximately 20 miles northeast of El Paso; 9.2 miles north of U.S. Highways 62 and 180; 106 degrees, 11 minutes, 04 seconds west longitude and 32 degrees, 57 minutes, 19 seconds north latitude. UTM zone 13, 388049E, 3535924N; NAD 27.

RANGE IN CHARACTERISTICS:

Soil Moisture: Intermittently moist in some part of the soil moisture control section during July through September and December through April. Driest during May and June. 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 69 degrees F.

Depth to Bw horizon: 4 to 10 inches

Depth to petrocalcic horizon: 20 to 40 inches

Depth to secondary carbonates: 4 to 20 inches

A horizon
Hue: 5YR, 7.5YR, 10YR
Value: 5 or 6 dry, 4 or 5 moist
Chroma: 4 to 6, dry or moist
Other features: The surface layer consists of recent eolian sand.

Bw horizon
Hue: 5YR, 7.5YR, 10YR
Value: 5 to 7 dry, 4 to 6 moist
Chroma: 4 to 6, dry or moist
Other features: The Bw horizons are weakly to strongly consolidated with bulk density of 1.91 .

Bkkm horizon
Hue: 7.5YR, 10YR
Value: 7 or 8, dry or moist
Chroma: 1 to 3, dry or moist

C horizon
Hue: 5YR, 7.5YR, 10YR
Value: 5 to 7 dry, 4 to 6 moist
Chroma: 4 to 6, dry or moist

COMPETING SERIES: This is the Harrisburg (UT) series. Harrisburg soils do not have massive 2Bw horizons, mean annual soil temperature that ranges from 59 to 63 degrees F. and have 2.5YR hue in the BW horizon.

GEOGRAPHIC SETTING: Nations soils are in nearly level to gently sloping wide basins between mountain ranges. Surfaces are plane with few to common brush coppice sand dunes. Slopes are mostly less than 3 percent. The regolith consists of very thick sandy to loamy bolson sediments many hundred feet deep. Elevations range from 3,000 to 4,200 feet. The climate is arid with average annual rainfall of 8 to 11 inches. Precipitation falls mostly during the months of July through September. The driest months are March and April. Precipitation during the months of January, February, and March is less than 13 percent of the total. The mean annual air temperature ranges from 62 degrees to 67 degrees F. The frost-free period is 200 to 240 days.

GEOGRAPHICALLY ASSOCIATED SOILS: These are the Copia, Hueco, and Wink soils. Copia soils do not have petrocalcic horizons and are on sand sheets on basin floors. Hueco soils have an argillic horizon above the petrocalcic horizon and are on basin floors. Wink soils are calcareous throughout and do not have petrocalcic horizons and are on basin floors.

DRAINAGE AND PERMEABILITY: Well drained; very slow runoff; permeability is moderately slow above the very slowly permeable petrocalcic horizon and rapid below the petrocalcic horizon.

USE AND VEGETATION: Used for livestock grazing. Vegetation is of the desert shrub type consisting of broom snakeweed, mesa dropseed, and spike dropseed.

DISTRIBUTION AND EXTENT: Trans-Pecos of Texas and southern New Mexico in MLRA 42. The series is of moderate extent.

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

SERIES ESTABLISHED: El Paso County, Texas; 2001.

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

Particle-size control section: The zone from 10 to 25 inches. (2Bw1 and 2Bw2 horizons)

Ochric epipedon - 0 to 5 inches (A horizon)

Petrocalcic horizon - 25 to 36 inches (2Bkm horizon)

Nations soils were formerly included in the Hueco series, which do not have massive 2Bw horizons.

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.