LOCATION STELLAR            NM+AZ 
Established Series
Rev. LHG/JBC/RLB
05/2007

STELLAR SERIES


The Stellar series consists of very deep, well drained soils that formed in sediments derived from such rocks as rhyolite, andesite, shale, and monzonite. Stellar soils are on basin floors and on toe-slopes of alluvial fans. Slopes are 0 to 5 percent. The mean annual precipitation is about 9 inches and the mean annual air temperature is about 67 degrees F.

TAXONOMIC CLASS: Fine, mixed, superactive, thermic Ustic Calciargids

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

A--0 to 3 inches; pinkish gray (7.5YR 6/2) clay loam, brown (7.5YR 4/3) moist; desiccation cracks 1/2-1 cm wide at surface become narrower with depth and form prisms 5-10 cm in diameter; prisms have moderate medium platy structure in upper part grading to weak coarse platy in lower part; slightly hard, friable, moderately sticky and moderately plastic; many roots; few tubular insect burrows 1-2 mm diameter; slightly effervescent; slightly alkaline; abrupt smooth boundary. (1 to 5 inches thick)

Bt1--3 to 7 inches; reddish brown (5YR 5/4) clay, reddish brown (5YR 4/4) moist; weak medium subangular blocky structure; hard, firm, moderately sticky and moderately plastic; common roots; few tubular insect burrows 2 mm in diameter; noneffervescent; slightly alkaline; clear smooth boundary. (3 to 9 inches thick)

Bt2--7 to 14 inches; reddish brown (5YR 4/4) clay, dark reddish brown (5YR 3/4) moist; moderate medium prismatic structure that parts to weak medium subangular blocky; very hard, firm, moderately sticky and moderately plastic; few roots; few calcium carbonate nodules less than 1 mm in diameter; effervescent; slightly alkaline; clear smooth boundary. (3 to 9 inches thick)

Bt3--14 to 19 inches; reddish brown (5YR 5/4) clay, reddish brown (5YR 4/4) moist; moderate medium prismatic structure that parts to weak medium subangular blocky; very hard, firm, moderately sticky and moderately plastic; few roots; few calcium carbonate nodules less than 1 mm in diameter; slightly effervescent; slightly alkaline; clear smooth boundary. (3 to 9 inches thick)

Btk--19 to 23 inches; reddish brown (5YR 5/4) clay, reddish brown (5YR 4/4) moist; some parts slightly redder and of higher chroma; moderate medium prismatic structure that parts to weak medium subangular blocky; very hard, firm, moderately sticky and moderately plastic; few roots; few calcium carbonate nodules less than 2 mm in diameter; effervescent; moderately alkaline; clear smooth boundary. (3 to 10 inches thick)

Bk1--23 to 28 inches; about equal parts of pinkish white (7.5YR 8/2) and light reddish brown (5YR 6/4) clay loam, pink (7.5YR 7/4) and reddish brown (5YR 4/4) moist; with 20 percent light brown (7.5YR 6/4); weak medium and fine subangular blocky structure; hard, friable, moderately sticky and moderately plastic; few roots; common calcium carbonate nodules and cylindroids; effervescent; moderately alkaline; clear wavy boundary. (0 to 7 inches thick)

Bk2--28 to 37 inches; pink (7.5YR 8/4) and light brown (7.5YR 6/4) clay loam, light brown (7.5YR 6/4) and brown (7.5YR 5/4) moist; weak medium subangular blocky structure; hard, friable, moderately sticky and moderately plastic; few roots; many calcium carbonate nodules and cylindroids; effervescent; moderately alkaline; clear wavy boundary. (6 to 10 inches thick)

Bk3--37 to 49 inches; light brown (7.5YR 6/4) sandy clay loam, brown (7.5YR 5/4) moist; massive; hard, friable, moderately sticky and slightly plastic; few roots; many calcium carbonate nodules and cylindroids; few fine tubular pores; effervescent; moderately alkaline; abrupt wavy boundary. (8 to 16 inches thick)

Bk4--49 to 59 inches; pinkish white (7.5YR 8/2) sandy clay loam, pink (7.5YR 7/4) moist; massive; hard, friable, moderately sticky and slightly plastic; common fine tubular pores; many calcium carbonate nodules and cylindroids; effervescent; moderately alkaline.

TYPE LOCATION: Dona Ana County, New Mexico; 400 feet West of the Jornada Road; SW 1/4 of section 4, T.21 S., R.2 E.

RANGE IN CHARACTERISTICS:

Soil moisture: Intermittently moist in some part of the soil moisture control section during December through April and July through September. Driest during May and June. This soil receives additional run in moisture from higher surrounding area ustic aridic soil moisture regime. Ustic aridic moisture regime.

Soil temperature: 61 to 72 degrees F.

Depth to calcic horizon: 20 to 40 inches

A horizon
Hue: 5YR to 10YR
Value: 4 to 6 dry, 3 to 5 moist
Chroma: 2 to 8, dry or moist
Texture: sandy loam, loam, sandy clay loam, silty clay loam, clay loam

Bt horizon
Hue: 2.5YR to 7.5YR
Value: 4 to 6 dry, 3 to 5 moist
Chroma: 3 to 8, dry or moist
Texture: clay, sandy clay, clay loam (35 to 50 percent clay)
Structure: prismatic, subangular blocky, or blocky, and ranges from weak to moderate
Effervescence: The upper part of the horizon ranges from noneffervescent to slightly effervescent

Bk horizon
Value: 6 to 9 dry, 5 to 8 moist; few darker spots in places
Chroma: 1 to 4, dry or moist
Texture: clay loam, silty clay loam, sandy clay loam
Calcium carbonate equivalent: more than 15 percent
Cementation: some pedons are strongly cemented but not continuously indurated

COMPETING SERIES: This is Bernardino (AZ), Forrest (AZ) and Penthouse (AZ) series.
Bernardino, Penthouse and Forrest soils are in the 12 to 16 inch precipitation zone.
Bernardino soils have calcic horizon at 5 to 20 inches, calcium carbonate equivalent averages 15 to 40 percent and decreases with increasing depth
Forrest and Penthouse soils contain 15 to 35 percent rock fragment in the particle size control section.

GEOGRAPHIC SETTING: The Stellar soils are on basin-floor positions and on toe-slopes of alluvial fans. Slopes range from 2 percent to level or nearly level. The soils formed in sediments of late or mid-Pleistocene age, and are derived from such rocks as rhyolite, andesite, shale, and monzonite. Elevations range from 2,600 to 5,800 feet. Mean annual air temperature ranges from about 59 to 70 degrees F. Mean annual precipitation ranges from 7 to 11 inches.

GEOGRAPHICALLY ASSOCIATED SOILS: These are the Algerita, Berino, Dona Ana, Headquarters, and Reakor soils. Algerita and Reakor soils do not have an argillic horizon. Berino, Dona Ana, and Headquarters soils have a fine-loamy control section.

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

USE AND VEGETATION: Used for livestock grazing and wildlife habitat. Vegetation is primarily tobosa. In some areas there is burrograss and scattered snakeweed, Yucca elata, mesquite, and tarbush. In places, grassy strips alternate with barren areas, several feet to a few tens of feet wide.

DISTRIBUTION AND EXTENT: Southern New Mexico and Arizona. The series is moderately extensive. MLRAs 41 and 42.

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

SERIES ESTABLISHED: Desert Soil-Geomorphology Project, Dona Ana County, New Mexico; 1971.

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

Ochric epipedon - The zone from 0 to 3 inches (A horizon)

Argillic horizon - The zone from 3 to 23 inches (Bt1, Bt2, Bt3 and Btk horizons)

Calcic horizon - The zone from 23 to 59 inches (Bk1, Bk2, Bk3 and Bk4 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.

Mean annual precipitation that ranges from 7 to 11 inches is too dry to qualify as Ustic aridic. The generally accepted range of precipitation in the Ustic aridic moisture regime is 12 to 16 inches. The issue is does the additional moisture contributed by run-on change the soil moisture regime? The dilemma is how to quantify the additions and losses. Determining the soil moisture regime is subjective at best. Attempting to account for run-on adds even more subjectivity to the process. For the purpose of assigning soil moisture regimes in this survey area, the guidelines consistent with what has been done in the adjoining MLRA 41 area should be followed.

ADDITIONAL DATA: Data from pedon S61 (65) NM-7-3 (L.H. Gile and R.B. Grossman. 1979. The Desert Project Soil Monograph. Document PB80-135304. National Technical Information Service, Springfield, VA.) support the classification. The typical pedon is the sampled pedon.


National Cooperative Soil Survey
U.S.A.