LOCATION YABAMAR            AZ
Established Series
Rev. DWD/CRP/PDC
10/2007

YABAMAR SERIES


The Yabamar series consists of shallow to weathered bedrock, well drained soils that formed in colluvium and residuum from calc-silicate hornfels and similar calcium rich metamorphic rocks. Yabamar soils are on hills and mountains. Slopes range from 60 to 80 percent. The mean annual precipitation is about 20 inches and the mean annual air temperature is about 60 degrees F.

TAXONOMIC CLASS: Loamy-skeletal, mixed, superactive, thermic, shallow Aridic Haplustolls

TYPICAL PEDON: Yabamar extremely cobbly loam - rangeland and wildlife habitat. (Colors are for dry soil unless otherwise noted.)

A1--0 to 2 inches; dark gray (10YR 4/1) extremely cobbly loam, black (10YR 2/1) moist; weak thick platy and subangular blocky structure parting to moderate very fine and fine granular; soft, very friable, slightly sticky and slightly plastic; many very fine roots; common very fine irregular pores; 30 percent gravel, 35 percent cobble and 5 percent stone; slightly effervescent; moderately alkaline (pH 8.2); abrupt smooth boundary.

A2--2 to 7 inches; dark gray (10YR 4/1) very cobbly loam, black (10YR 2/1) moist; moderate very fine and fine subangular blocky and moderate very fine and fine granular structure; soft, very friable, slightly sticky and slightly plastic; common very fine and few fine, medium and coarse roots; common very fine and fine irregular pores; 15 percent gravel, 15 percent cobble and 5 percent stone; strongly effervescent; moderately alkaline (pH 8.2); clear smooth boundary. (Combined thickness of the A horizons is 5 to 12 inches)

2AC--7 to 12 inches; grayish brown (10YR 5/2) very gravelly loam, very dark grayish brown (10YR 3/2) moist; moderate fine subangular blocky structure; slightly hard, friable, slightly sticky and slightly plastic; common very fine and few fine, medium and coarse roots; common very fine and fine irregular pores; 30 percent gravel, 10 percent cobble; violently effervescent; moderately alkaline (pH 8.2); abrupt smooth boundary. (3 to 10 inches thick)

2Cr--12 inches; weathered calc-silicate hornfels.

TYPE LOCATION: Coronado National Memorial; located at a latitude of 31 degrees, 21 minutes, 56 seconds North and longitude of 110 degrees, 14 minutes, 1 second West.

RANGE IN CHARACTERISTICS:

Soil moisture: Intermittently moist in some part of the soil moisture control section during July to September and December to February. Driest during May and June. Aridic ustic soil moisture regime.

Soil Temperature: 59 to 64 degrees F.

Rock fragments: averages 35 to 60 percent

Calcium carbonate equivalent: 5 to 15 percent

Depth to weathered bedrock: 10 to 20 inches

Depth to unweathered bedrock: 20 to 40 inches

Clay content: 12 to 18 percent

Organic matter: 1 to 3 percent in the surface layer

A horizon
Value: 4 or 5 dry, 2 or 3 moist
Chroma: 1 or 2, dry or moist

AC horizon
Value: 5 or 6 dry, 3 or 4 moist

COMPETING SERIES: This is the Bothompeek (AZ) series. Bothompeek soils formed in colluvium and residuum from shale, siltstone and fine grained sandstone, have a lithic contact below the paralithic contact, and are slightly acid to slightly alkaline.

GEOGRAPHIC SETTING: Yabamar soils are on hills and mountains at elevations of 5600 to 7400 feet. Slopes range from 60 to 80 percent. These soils formed in colluvium and residuum from calcium rich metamorphic rock. The mean annual precipitation is 18 to 23 inches and occurs as thunderstorms during July to September and as gentle rains during December to February. The mean annual air temperature is 57 to 62 degrees F. The frost-free period is 160 to 210 days.

GEOGRAPHICALLY ASSOCIATED SOILS: This is the Bothompeek soil. Bothampeek soils are formed from shale, siltstone and fine grained sandstone and are moderately acid to slightly alkaline.

DRAINAGE AND PERMEABILITY: Well drained; rapid runoff; moderate permeability.

USE AND VEGETATION: Used for livestock grazing and wildlife habitat. Vegetation includes Emory oak , birchleaf mountain mahogany, ocotillo, sotol, bull grass, Lehmans lovegrass, plains lovegrass, sideoats grama.

DISTRIBUTION AND EXTENT: Southern Arizona. Yabamar soils are of limited extent. MLRA is 41.

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

SERIES ESTABLISHED: Cochise County, Arizona; Soil survey of Coronado National Memorial; 1996.

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

Mollic epipedon - The zone from 0 to 12 inches (A1, A2, 2AC horizons)

Paralithic contact - The boundary at 12 inches (2Cr horizon)

Classified according to Soil Taxonomy Second Edition, 1999; Keys to Soil Taxonomy Tenth Edition, 2006.


National Cooperative Soil Survey
U.S.A.