LOCATION LEHMANS AZ+NMEstablished Series
TAXONOMIC CLASS: Clayey, smectitic, thermic Lithic Haplargids
TYPICAL PEDON: Lehmans gravelly clay loam - rangeland. (Colors are for dry soil unless otherwise noted.)
A--0 to 1 inch; brown (7.5YR 5/2) gravelly clay loam, dark brown (7.5YR 3/2) moist; moderate fine granular structure; slightly hard, friable, sticky and plastic; common fine roots; many fine interstitial pores; noneffervescent; moderately alkaline (pH 8.0); abrupt wavy boundary. (1 to 2 inches thick)
Bt1--1 to 8 inches; reddish brown (5YR 5/3) gravelly clay, reddish brown (5YR 4/4) moist; moderate medium and fine subangular blocky structure; very hard, friable, sticky and plastic; common very fine and few coarse roots; few fine tubular and common fine irregular pores; many faint clay films on faces of peds and lining pores; noneffervescent; neutral (pH 7.0); clear wavy boundary. (5 to 12 inches thick)
Bt2--8 to 14 inches; brown (7.5YR 5/4) clay, brown (7.5YR 4/4) moist; weak medium subangular blocky structure; hard, firm, sticky and plastic; common very fine roots; few fine tubular and common fine irregular pores; common faint clay films on faces of peds and lining pores; noneffervescent; neutral (pH 6.6); abrupt wavy boundary. (0 to 6 inches thick)
2R--14 inches; andesite.
TYPE LOCATION: Yavapai County, Arizona, about .5 miles northwest of Castle Hot Springs Post Office; 1,320 feet south and 660 feet east of northwest corner of section 22, T. 8 N., R. 1 W. Latitude 34 degrees, 1 minute 26 seconds N., Longitude 112 degrees, 21 minutes, 27 seconds W., NAD 83.
RANGE IN CHARACTERISTICS:
Soil moisture: Intermittently moist in some part of the soil moisture control section during July-September and December-January. Driest during May and June. Typic aridic soil moisture regime.
Soil temperature: 59 to 72 degrees F.
Rock fragments: averages 10 to 30 percent
Depth to bedrock: 6 to 20 inches; but dominantly 14 to 18 inches
Organic matter content: less than 1 percent
Reaction: neutral to moderately alkaline
A horizon
Hue: 5YR, 7YR, 10YR
Value: 4 through 6 dry, 3 or 4 moist
Chroma: 2, 3, 4, or 6, dry or moist
B horizon
Hue: 2.5YR, 5YR, 7.5YR
Value: 4 or 5 dry, 3, 4, or 5 moist
Chroma: 3 4, or 6, dry or moist
Texture: clay loam, clay (35 to 60 percent clay)
COMPETING SERIES: There are no competing series.
GEOGRAPHIC SETTING: Lehmans soils are on pediments and hills. Slopes range from 5 to 60 percent. These soils formed in slope alluvium from andesite, basalt, rhyolite, tuff, and volcanic breccia. Elevations range from 1700 to 4000 feet. The mean annual precipitation is 8 to 13 inches and occurs mainly as thunderstorms in July and August and as gentle rains in December-February. The mean annual air temperature is 57 to 70 degrees F. The frost-free period is 180 to 280 days.
GEOGRAPHICALLY ASSOCIATED SOILS: These are the Cellar, Continental, House Mountain, and Rimrock soils. Cellar and House Mountain soils lack an argillic horizon. Continental soils are more than 20 inches deep and are clayey. Rimrock soils are more than 20 inches deep and lack an argillic horizon.
DRAINAGE AND PERMEABILITY: Well drained; medium runoff; slow permeability.
USE AND VEGETATION: Used for livestock grazing. Vegetation is mainly paloverde, jojoba, false mesquite, ocotillo, saguaro, barrel and prickly pear cacti, slender grama, sideoats grama, tobosa, curlymesquite and annual forbs.
DISTRIBUTION AND EXTENT: Southern Arizona and southern New Mexico. The Lehmans soils are extensive. Total extent is about 415,000 acres. MLRAs are 40, 41, and 42.
MLRA SOIL SURVEY REGIONAL OFFICE (MO) RESPONSIBLE: Phoenix, Arizona
SERIES ESTABLISHED: Yavapai County, Arizona, Western Part; 1971.
REMARKS: Diagnostic horizons and features recognized in this pedon are:
Ochric epipedon - the zone from 0 to 1 inch (A horizon)
Argillic horizon - the zone from 1 to 14 inches (Bt1, Bt2 horizons)
Lithic contact - the boundary at 14 inches (2R horizon)
Classified according to Soil Taxonomy, Second Edition, 1999; Keys to Soil Taxonomy, Tenth Edition, 2006.