Established Series


The Apache series consists of soils that are very shallow and shallow to basalt bedrock. They are well drained, moderately permeable soils that formed in a thin layer of material weathered from basalt and eolian sediments. Apache soils are on the outer margins of basalt flows and mesas. Slope ranges from 1 to 30 percent. The mean annual precipitation is about 16 inches; the mean annual temperature is about 53 degrees F.

TAXONOMIC CLASS: Loamy, mixed, superactive, mesic Lithic Haplustolls

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

A--0 to 8 inches; dark grayish brown (10YR 4/2) cobbly loam, very dark grayish brown (10YR 3/2) moist; weak medium subangular blocky structure; soft, slightly sticky; many fine and medium roots; common fine and medium tubular pores; many dark mineral grains in the sand and silt size fraction; few small hard calcium carbonate nodules; 15 to 20 percent cobbles, few pebbles, few stones all of basalt; strongly calcareous; moderately alkaline; clear smooth boundary. (3 to 9 inches thick)

Bk1--8 to 12 inches; brown (10YR 5/3) cobbly clay loam, brown (10YR 4/3) moist; moderate fine subangular blocky structure; slightly hard, firm, slightly sticky; common fine and medium roots; common fine tubular pores; many dark mineral grains in the sand and silt size fraction; few small hard calcium carbonate concretions in lower part; 20 to 35 percent rock fragments of basalt, mostly cobbles, few pebbles and stones; strongly calcareous; moderately alkaline; clear wavy boundary. (0 to 8 inches thick)

Bk2--12 to 16 inches; very pale brown (10YR 8/3) cobbly clay loam, very pale brown (10YR 8/2) moist; soft to slightly hard calcium carbonate nodules; many dark ferromagnesian mineral grains in the sand and silt size fraction; 30 to 35 percent rock fragments of basalt, mostly stones, few cobbles and pebbles; underside of rock fragments are coated with calcium carbonate that are laminar in places, coatings range from 2 to 5mm thick and the laminar part from 1 o 2 mm. thick; moderately alkaline; abrupt wavy boundary. (0 to 6 inches thick)

R--16 inches; fractured; hard black basalt coated with white calcium carbonate.

TYPE LOCATION: Union County, New Mexico; 720 feet north of railroad track and 1,664 feet west of intersecting of ranch road with railroad track; NE 1/4 sec. 24, T. 26 N., R. 34 E.

Soil moisture: Ustic moisture regime bordering on Aridic. Moist intermittently April through August. December through February are the driest months.

The surface is covered with 5 to10 percent basalt fragments and hard calcium carbonate nodules usually less than 3 inches in size.

Depth to lithic content: typically 10 to 20 inches but ranges to 4 inches
Calcium carbonate equivalent: 5 to 25 percent, but any horizon containing more than 15 percent is less than 6 inches thick. Carbonates are distributed throughout the soil, both disseminated and segregated.

Particle size control section:
Clay content: 18 to 35 percent
Rock fragment content: 5 to 35 percent mostly pebbles and cobbles

A horizon
Hue: 7.5YR or 10YR
Value: 4 or 5 dry, 2 or 3 moist
Chroma: 2 or 3
Texture of the fine earth fraction: loam, clay loam, or sandy loam
Organic matter: 1 to 5 percent

Bk horizons
Hue: 7.5YR or 10YR
Value: 4 to 8 dry and 2 to 5 moist
Chroma: 1 to 4
Texture of the fine earth fraction: Sandy loam, loam, sandy clay loam or clay loam.
Clay content: 18 to 35 percent.
Calcium carbonate content: 5 to 15 percent

COMPETING SERIES: These are the Altezita (T NM), Hedville (KS), and Sogn (KS) series. Potential competitors were a superactive activity class assigned are the Dalerose ((T CO), Purner (AZ), Santana (NM), and Venezia (AZ) soils.
Altezita and Hedville soils: do not contain secondary carbonates in the series control section, and contain coarse fragments of sandstone in the control section.
Sogn soils: are moist in the soil moisture control section for significantly longer periods of time (udic/ustic), and are derived from Pennsylvanian Limestone.
Dalerose soils: averages 5 to 18 percent clay in the particle size control section.
Purmer soils: have hue of 2.5YR or 5YR.
Santana soils: contain fragments of granite in the series control section.

Venezia soils: do not contain secondary carbonates, and receive winter precipitation.

Landform: commonly on the outer margins of basalt mesas, lava plateaus and in lava flow areas. The topography is nearly level to moderately steep.
Parent material: a thin layer of residuum weathered from basalt, small amounts of eolian material, and other volcanic debris.
Elevation: 5,000 to 8,200 feet
Slope: 1 to 30 percent
Mean annual soil temperature: 46 to 55 degrees F., PE index of 25
Mean summer temperature: 68 to 72 degrees F.
Mean annual Precipitation: 13 to 17 inches.
Frost-free period: 115 to 175 days

GEOGRAPHICALLY ASSOCIATED SOILS: These are the Ayon, Capulin, La Brier, and Torreon series.
The Ayon, Capulin, La Brier, and Torreon soil are greater than 20 inches to bedrock.

DRAINAGE AND PERMEABILITY: Well drained, runoff is high on slopes less than 1 percent and very high on slopes greater than 1 percent; moderate permeability.

USE AND VEGETATION: Use is exclusively for rangeland and wildlife habitat. The principal vegetation is blue grama, little bluestem, sideoats grama, some snakeweed, and cacti.

DISTRIBUTION AND EXTENT: New Mexico, southern Colorado, western Oklahoma, and Arizona. LRR G, MLRA 70; This series is extensive.


SERIES ESTABLISHED: The Mansker Soil Conservation Demonstration Project, northeastern New Mexico, 1938.

REMARKS: Where this series is used in Arizona and western New Mexico the mean annual precipitaion ranges to 12 inches.

Diagnostic horizons and features recognized in this pedon are:

Mollic epipedon: 0 to 8 inches. (A horizon)
Lithic contact: Bedrock at 16 inches.

Taxonomic Version: Second Edition, 1999

National Cooperative Soil Survey