LOCATION LIGURTA AZEstablished Series
TAXONOMIC CLASS: Fine-loamy, mixed, superactive, hyperthermic Calcic Haplosalids
TYPICAL PEDON: Ligurta very gravelly loam - desert. (Colors are for dry soil unless otherwise noted.) 90 to 95 percent of the surface is covered with gravel, thin coat of desert varnish on gravel.
Az--0 to 2 inches; very pale brown (10YR 7/4) extremely gravelly loam, dark yellowish brown (10YR 4/4) moist; moderate medium platy structure; slightly hard, very friable, slightly sticky and slightly plastic; few very fine roots; few very fine vesicular pores; 50 percent fine and medium gravel; strongly effervescent; moderately alkaline (pH 8.2); strongly saline; abrupt smooth boundary. (1 to 3 inches thick)
Btz1--2 to 5 inches; reddish yellow (7.5YR 7/6) gravelly clay loam, dark reddish brown (5YR 3/4) moist; moderate and strong fine granular structure; loose, sticky and plastic; few very fine roots; many very fine irregular pores; 15 percent fine gravel; strongly effervescent; moderately alkaline (pH 8.2); strongly saline; clear wavy boundary. (2 to 10 inches thick)
Btkz1--5 to 10 inches; yellowish red (5YR 4/6) gravelly clay loam, dark reddish brown (5YR 3/4) moist; moderate and strong fine granular structure; loose, moderately sticky and moderately plastic; few very fine roots; many very fine irregular pores; few faint clay films on faces of peds and in pores; 20 percent fine and medium gravel; strongly effervescent with common soft calcium carbonate masses; common very fine and fine salt crystals; moderately alkaline (pH 8.2); strongly saline; clear wavy boundary. (5 to 8 inches thick)
Btkz2--10 to 15 inches; yellowish red (5YR 5/6) gravelly clay loam, dark reddish brown (5YR 3/4) moist; weak fine and medium subangular blocky structure; hard, friable, moderately sticky and moderately plastic; many very fine tubular pores; common faint clay films on faces of peds and in pores; 25 percent fine and medium gravel; strongly effervescent with common soft calcium carbonate masses; common very fine and fine salt crystals; moderately alkaline (pH 8.2); strongly saline; clear wavy boundary. (4 to 7 inches thick)
Btkz3--15 to 28 inches; light reddish brown (5YR 6/3) clay loam, reddish brown (5YR 4/3) moist; moderate fine and medium subangular blocky structure; hard, friable, moderately sticky and moderately plastic; many very fine tubular pores; few faint clay films on faces of peds and in pores; 10 percent fine and medium gravel; strongly effervescent with common soft calcium carbonate masses; common very fine and fine salt crystals; moderately alkaline (pH 8.2); strongly saline; clear wavy boundary. (8 to 15 inches thick)
Btkz4--28 to 40 inches; light reddish brown (5YR 6/3) gravelly clay loam, reddish brown (5YR 4/3) moist; moderate fine and medium subangular blocky structure; hard, friable, moderately sticky and moderately plastic; many very fine tubular pores; few faint clay films on faces of peds and in pores; 15 percent fine gravel; strongly effervescent with common soft calcium carbonate masses; common very fine and fine salt crystals; moderately alkaline (pH 8.2); strongly saline; gradual wavy boundary. (7 to 16 inches thick)
Bk--40 to 60 inches; light reddish brown (5YR 6/3) gravelly loam, reddish brown (5YR 4/3) moist; massive; hard, friable, slightly sticky and slightly plastic; few very fine tubular pores; few faint clay films in pores; 15 percent fine gravel; strongly effervescent with common soft calcium carbonate masses; common very fine and fine salt crystals; moderately alkaline (pH 8.2); strongly saline.
TYPE LOCATION: Yuma County, Arizona; about 0.7 miles northeast of White Wing Ranch Headquarters; about 2,000 feet east and 500 feet north of the northeast corner of section 23, T.5S., R.12W.
RANGE IN CHARACTERISTICS:
Soil moisture: Intermittently moist in the soil moisture control section during July - September and December - February. Driest during May and June. Typic aridic soil moisture regime.
Electrical conductivity: 25 to more than 100 dS/m but averages 35 to 50
Rock fragments: less than 35 percent
Az horizon
Hue: 7.5YR, 10YR
Value: 5 through 7 dry, 3 through 6 moist
Chroma: 2 through 4, dry or moist
Texture: extremely gravelly loam, very gravelly loam, extremely gravelly sandy clay loam, extremely gravelly clay loam
Bt horizons
Hue: 10YR through 5YR
Value: 4 through 6 dry, 3 through 5 moist
Chroma: 4 through 6, dry or moist
Texture: gravelly loam, gravelly sandy clay loam, gravelly clay loam, loam, sandy clay loam or clay loam
COMPETING SERIES: There are no competing series.
GEOGRAPHIC SETTING: Ligurta soils are on fan terraces on slopes of 0 to 6 percent. Elevations are 250 to 1,300 feet. These soils formed in fan alluvium weathered from andesite, rhyolite, basalt, granite, gneiss and schist. The mean annual precipitation is 2 to 6 inches and the mean annual air temperature is 72 degrees to 76 degrees F. The frost-free period is 250 to 365 days.
GEOGRAPHICALLY ASSOCIATED SOILS: These are the Cristobal, Harqua, Tremant and Carrizo soils. These soils do not have salic horizons.
DRAINAGE AND PERMEABILITY: Well drained; rapid runoff; moderately slow permeability.
USE AND VEGETATION: Used for livestock grazing and wildlife habitat. The soil is nearly barren of vegetation except in the small drainages. Vegetation in the drainages is creosotebush, plantain, fiddleneck, filaree, turkshead, pencil cholla and saguaro.
DISTRIBUTION AND EXTENT: Southwestern Arizona and southeastern California. Ligurta soils are extensive. MLRA is 40.
MLRA SOIL SURVEY REGIONAL OFFICE (MO) RESPONSIBLE: Phoenix, Arizona
SERIES ESTABLISHED: Yuma County (Yuma-Wellton Area), Arizona; 1978.
REMARKS: Diagnostic horizons and features recognized in this pedon are:
Ochric epipedon - The zone from 0 to 2 inches (Az horizon)
Argillic horizon - The zone from 2 to 40 inches (Btz, Btkz1, Btkz2, Btkz3, Btkz4 horizons)
Salic horizon - The zone from 5 to 60 inches (Btkz1, Btkz2, Btkz3, Btkz4 horizons)
Calcic horizon - The zone from 5 to 60 inches (Btkz1, Btkz2, Btkz3, Btkz4 Bk horizons)