LOCATION ONATE              NM 
Established Series
Rev. LHG/CEM/PDC
12/2006

ONATE SERIES


The Onate series consists of very deep, well drained soils that formed in alluvium derived dominantly from igneous rocks and mixed sources. Onate soils are on alluvial fans and fan piedmonts with slopes of 4 to 15 percent. The mean annual precipitation is about 11 inches and the mean annual air temperature is about 60 degrees F.

TAXONOMIC CLASS: Coarse-loamy, mixed, superactive, thermic Aridic Argiustolls

TYPICAL PEDON: Onate gravelly sandy loam - rangeland. (Colors are for dry soil unless otherwise noted.)

A--0 to 2 inches; brown (7.5YR 5/2) gravelly loamy sand, dark brown (7.5YR 3/2) moist; weak medium platy structure; soft, very friable, nonsticky and nonplastic; few fine and very fine roots; 15 percent gravel; slightly alkaline; abrupt smooth boundary. (1 to 4 inches thick)

BAt--2 to 8 inches; brown (7.5YR 4/2) gravelly sandy loam, very dark brown (7.5YR 2/2) moist; weak coarse subangular blocky structure; hard and very hard, very friable, nonsticky and nonplastic; common fine and very fine roots beneath grass clumps; sand grains and gravel coated with oriented clay; 15 percent gravel; slightly alkaline; clear wavy boundary. (4 to 9 inches thick)

Bt1--8 to 16 inches; brown (7.5YR 4/2) gravelly sandy loam, very dark brown (7.5YR 2.5/2) moist; weak coarse subangular blocky structure; very hard, friable, nonsticky and nonplastic; few fine and very fine roots; sand grains and gravel coated with oriented clay; 20 percent gravel; slightly alkaline; clear wavy boundary. (6 to 10 inches thick)

Bt2--16 to 24 inches; brown (7.5YR 4/2) gravelly sandy loam, very dark brown (7.5YR 2.5/2) moist; weak coarse subangular blocky structure; very hard, friable, nonsticky and nonplastic; few fine and very fine roots; sand grains and pebbles coated with oriented clay; 20 percent gravel; slightly alkaline; clear wavy boundary. (6 to 10 inches thick)

Bt3--24 to 30 inches; brown (7.5YR 4/2) gravelly sandy loam, very dark brown (7.5YR 2.5/2) moist; weak coarse subangular blocky structure; very hard, friable, nonsticky and nonplastic; few fine and very fine roots; sand grains and gravel coated with oriented clay; 20 percent gravel; slightly alkaline; clear wavy boundary. (5 to 9 inches thick)

Bt4--30 to 38 inches; brown (7.5YR 4/2) gravelly loamy sand, dark brown (7.5YR 3/2) moist; weak coarse subangular blocky structure; hard, very friable, nonsticky and nonplastic; few fine roots; sand grains and gravel coated with oriented clay; 20 percent gravel; slightly alkaline; clear wavy boundary. (0 to 10 inches thick)

BCt--38 to 48 inches; brown (7.5YR 5/3) gravelly sand, dark brown (7.5YR 3/3) moist; massive; soft and slightly hard, very friable, nonsticky and nonplastic; few fine roots; sand grains and gravel coated with oriented clay; 20 percent gravel; slightly alkaline; clear wavy boundary. (0 to 12 inches thick)

Ck1--48 to 57 inches; brown (7.5YR 5/3) gravelly sand, dark brown (7.5YR 3/3) moist; massive; soft, very friable, nonsticky and nonplastic; few fine roots; 20 percent gravel; the fine earth is slightly effervescent in places; thin discontinuous calcium carbonate coatings on some gravel; slightly alkaline; clear wavy boundary. (4 to 12 inches thick)

Ck2-- 57 to 64 inches; brown (7.5YR 5/3) gravelly sand, dark brown (7.5YR 3/3) moist; massive; soft, very friable, nonsticky and nonplastic; few fine roots; 20 percent gravel; the fine earth is slightly effervescent in places; thin discontinuous calcium carbonate coatings on some gravel; slightly alkaline.

TYPE LOCATION: Dona Ana County, New Mexico; about 1300 feet east of road in north bank of gully; SE 1/4, SW 1/4, NE 1/4 of section 36, T.21 S., R.3 E; 106 degrees 35 minutes 6 seconds west longitude and 32 degrees 26 minutes 20 seconds north latitude.

RANGE IN CHARACTERISTICS:

Soil Moisture: Intermittently moist in some part of the soil moisture control section during December through April and for more than 20 days cumulative during July through September. Driest during May and June. Ustic aridic soil moisture regime.

Soil Temperature: 62 to 68 degrees F.

Clay content: averages less than 18 percent clay

Rock fragments: Averages 5 to 35 percent

Organic matter: more than 1 percent in the surface

Calcium carbonate: The A and Bt horizons of these soils are typically noncalcareous, but the lower parts of some Bt horizons may effervesce

A horizon
Hue: 7.5YR, 10YR
Value: 3 through 5 dry, 1 through 3 moist
Chroma: 1 through 3, dry or moist

Bt horizon
Hue: 10YR through 5YR
Value: 3 through 6 dry, 1 through 4 moist
Chroma: 1 through 4, dry or moist

C horizon
Hue: 7.5YR, 10YR
Value: 4 through 6 dry, 3 through 5 moist
Chroma: 2 through 4, dry or moist

COMPETING SERIES: There are no competing series.

GEOGRAPHIC SETTING: Onate soils are on slightly concave positions on alluvial fans and fan-piedmonts. Slopes range from 4 to 15 percent. Elevations range from 5,000 to 6,000 feet. The mean annual precipitation ranges from 10 to 13 inches. The mean annual air temperature ranges from 57 to 63 degrees F. The frost-free period is about 170 to 200 days.

GEOGRAPHICALLY ASSOCIATED SOILS: These are the Aladdin, Earp, Hap, Hawkeye, and Monza soils. Earp and Monza soils are loamy-skeletal. Aladdin and Hawkeye soils do not have argillic horizons. Hap soils are fine-loamy.

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

USE AND VEGETATION: Used for livestock grazing and wildlife habitat. Vegetation consists of blue grama, three-awn, Mormon tea, mesquite, snakeweed and soaptree yucca.

DISTRIBUTION AND EXTENT: Southern New Mexico. The series is inextensive. MLRA is 42.

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

SERIES ESTABLISHED: Dona Ana County, New Mexico (Desert Project); 1997.

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

Mollic epipedon - The zone from 0 to 16 inches (A, BAt, Bt1 horizons)

Argillic horizon - The zone from 2 to 30 inches (BAt, Bt1, Bt2, Bt3 horizons)

This series represents an identified soil within the Desert Soil-Geomorphology Project, Las Cruces, New Mexico. The project was a study of soils and geomorphology in an arid and semi-arid environment. The series is extensively referenced in many documents, publications and thesis. Revision outside the project area is discouraged in order to preserve the historical concept for research.

ADDITIONAL DATA: Data for a similar pedon (S59NM-7-1) have been presented (L.H. Gile and R.B. Grossman. 1979. The Desert Project Soil Monograph. Document PB80-135304. National Technical Information Service, Springfield, VA.


National Cooperative Soil Survey
U.S.A.