LOCATION BRIDGE AZEstablished Series
TAXONOMIC CLASS: Fine-loamy, mixed, superactive, thermic Typic Haplocalcids
TYPICAL PEDON: Bridge cobbly loam, rangeland. (Colors are for dry soil unless otherwise noted.)
A1--0 to 2 inches; pinkish gray (7.5YR 6/2) cobbly loam, brown (7.5YR 5/4) moist; weak fine granular structure; soft, friable, slightly sticky, slightly plastic; few fine roots; common very fine pores; few fine irregular pores; strongly effervescent; moderately alkaline (pH 8.2); clear smooth boundary. (2 to 4 inches thick)
A2--2 to 6 inches; pinkish gray (7.5YR 6/2) gravelly light clay loam, brown (7.5YR 5/2) moist; weak fine and medium granular structure; slightly hard, friable, sticky, plastic; few fine roots; common and very fine irregular pores; violently effervescent; moderately alkaline (pH 8.2); clear wavy boundary. (3 to 7 inches thick)
Bw--6 to 17 inches; pinkish gray (7.5YR 6/2) light sandy clay loam, brown (7.5YR 5/4) moist; structureless, massive; slightly hard, friable, sticky, plastic; few fine medium and coarse roots; common very fine irregular pores; violently effervescent; moderately alkaline (pH 8.4); gradual wavy boundary. (9 to 12 inches thick)
Bk--17 to 24 inches; pinkish gray (7.5YR 6/2) gravelly heavy sandy loam, brown (7.5YR 5/4) moist structureless, massive; hard, friable, slightly sticky, slightly plastic; few fine roots; few very fine irregular pores; common, large irregular lime masses; violently effervescent; moderately alkaline (pH 8.4); gradual wavy boundary. (6 to 15 inches thick)
2Cr--24 to 40 inches; weathered tuff and ash.
TYPE LOCATION: Yavapai County, Arizona; SE1/4 sec. 20, T.14N., R.6E., Long Valley Survey Area, Arizona.
RANGE IN CHARACTERISTICS:
Depth to underlying ash or tuff: 20 to 38 inches
Organic matter: less than 1 percent
Mean annual soil temperature: 59 degrees to 65 degrees F.
Soil moisture: usually dry between depths of 7 and 20 inches. Typic aridic moisture regime.
Rock fragments: less than 35 percent coarse fragments
Effervescence: Nearly all of the soil is strongly to violently effervescent throughout, but a few pedons are noneffervescent in the A horizon.
A1 horizon
Hue: 10YR or 7.5YR
Value: 5 through 7 dry and 3 through 5 moist
Chroma of 2 through 4.
Texture: gravelly sandy loam, stony loam, very gravelly loam, or cobbly loam.
B horizons
Hue: 10YR or 7.5YR,
Value: 5 through 8 dry and 4 through 6 moist
Chroma: 2 through 4
Texture: gravelly or cobbly sandy loam, gravelly or cobbly loam, gravelly or cobbly sandy clay loam, gravelly clay loam.
Clay content: 18 to 35 percent
Cr horizon
The proportions of weathered tuff and ash in the C3 horizon is variable.
COMPETING SERIES: These are the Chutum (AZ), Deltajo (NM), Laverkin (UT), Sotim (NM), Turney (NM) and Weedpatch (CA) series. Chutum, Laverkin, Sotim, Turney and Weedpatch soils are very deep. Deltajo soils are moderately deep to sandstone and siltstone and have hues redder than 5YR. In addition, Weedpatch soils are in the San Joaquin Valley (MLRA 17) receive mostly winter precipitation and are usually dry from April through November.
GEOGRAPHIC SETTING: Bridge soils are on hillslopes at elevations ranging from 3,500 to 4,000 feet. Slopes are dominantly 2 to 20 percent and range from 0 to 30 percent. Bridge soils formed in slope alluvium in part from basalt and limestone and in part from volcanic ash and tuff. Mean annual precipitation is about 12 inches, mean annual temperature is about 60 degrees F., mean January temperature is about 41 degrees F., and mean July temperature is about 78 degrees F.
GEOGRAPHICALLY ASSOCIATED SOILS: These are the Guest, Hantz, House Mountain, Mescal, Penthouse, and Retriever soils. Guest and Hantz soils have fine texture and lack calcic horizons. House Mountain and Retriever soils are shallow. Mescal soils have 5YR hue and lack calcic horizons. Penthouse soils contain more than 1 percent organic matter and have argillic horizons of fine texture.
DRAINAGE AND PERMEABILITY: Well drained. Surface runoff is medium. Permeability is moderate.
USE AND VEGETATION: Used for winter range from livestock and big game. The vegetation is juniper, canotia, mesquite, algerita, cacti, yucca, snakeweed, sand dropseed, sideoats grama, and fluffgrass.
DISTRIBUTION AND EXTENT: Central and southern Arizona. The series is of small extent. MLRA 38.
MLRA SOIL SURVEY REGIONAL OFFICE (MO) RESPONSIBLE: Phoenix, Arizona
SERIES ESTABLISHED: Beaver Creek Area, Yavapai County, Arizona, 1965.
REMARKS: Diagnostic horizons and features recognized in this pedon are:
Ochric epipedon - The zone from 0 to 6 inches (A horizons)
Calcic horizon - The zone from 17 to 24 inches (Bk horizon)
Classified according to Soil Taxonomy Second Edition, 1999