LOCATION ZILDITLOI AZ+NMEstablished Series
TAXONOMIC CLASS: Mixed, frigid Typic Ustipsamments
TYPICAL PEDON: Zilditloi loamy sand, stony -- on a backslope of an escarpment sloping 86 percent to the southeast at 8,200 feet elevation -- woodland. (Colors are for dry soil unless otherwise noted.)
A--0 to 7 inches; brown (10YR 5/3) loamy sand, brown (10YR 4/3) moist; weak medium platy structure parting to weak medium granular; soft, very friable, nonsticky and nonplastic; common medium and many very fine roots; 5 percent channers, 5 percent flagstones, and 1 percent stones; slightly alkaline; clear wavy boundary. (2 to 7 inches thick)
C1--7 to 31 inches; very pale brown (10YR 7/3) sand, pale brown (10YR 6/3) moist; massive; soft, very friable, nonsticky and nonplastic; few coarse and very fine roots; vertical to angled cracks that are 0.5 to 1.5 inches wide and filled with pinkish gray (7.5YR 6/2) calcareous loamy sand; calcium carbonate segregated on sand grains and root surfaces in the cracks; slightly alkaline; clear wavy boundary. (12 to 28 inches thick)
C2--31 to 70 inches; very pale brown (10YR 7/3) sand, pale brown (10YR 6/3) moist; massive; hard, friable, nonsticky and nonplastic; few coarse and very fine roots concentrated in, but not restricted to cracks; 10 percent soft sandstone fragments; vertical to angled cracks that are 0.5 to 1.5 inches wide and filled with pinkish gray (7.5YR 6/2) calcareous loamy sand; calcium carbonate segregated on sand grains and root surfaces in the cracks; slightly alkaline.
TYPE LOCATION: Apache County, Arizona; on the Navajo Indian Reservation about 14.5 miles south of Red Rock; 1,350 feet east and 2,050 feet north of the southwest corner of sec. 31, T.35N., R.31E.; Latitude 36 degrees 23 minutes 44 seconds N and Longitude 109 degrees 2 minutes 59 seconds W.
RANGE IN CHARACTERISTICS:
Soil moisture - The soil moisture control section is moist in all parts from January to May and intermittently moist in some part from July to September. The soil is driest during June. Typic ustic soil moisture regime.
Soil temperature: 42 to 45 degrees F.
Silicate clay content: 2 to 8 percent
Rock fragments: less than 5 percent in the particle-size control section. Ranges to 15 percent in the surface and consists of up to 5 percent channers and/or flagstones and 1 to 3 percent stones.
Reaction: slightly acid to mildly alkaline
A horizon
Hue: 5YR, 7.5YR, 10YR
Value: 3 through 6, dry or moist
Chroma: 2 through 4, dry or moist
C horizon
Hue: 5YR, 7.5YR, 10YR
Value: 4 through 7, dry or moist
Chroma: 2 through 6, dry or moist
Texture: sand, fine sand, loamy fine sand
Calcium carbonate equivalent: 0 to 1 percent
Other features: 0 to 25 percent soft sandstone fragments
COMPETING SERIES: These are the Beisigl (ND), Blanchard (MT), Kenray (NM), Seroco (ND), and Yecross (SD) series. Beisigl soils have a paralithic contact at depths of 20 to 40 inches. Blanchard and Yecross soils are calcareous in the control section. Seroco soils are moist in some or all parts of the soil moisture control section during June. Kenray soils have soil temperatures of 45 to 47 degrees and are dry in all parts of the soil moisture control section in May.
GEOGRAPHIC SETTING: Zilditloi soils are on backslopes of escarpments on mountains. Zilditloi soils formed in alluvium, colluvium, and residuum derived from Tertiary sandstone. Slopes are 35 to 90 percent. Elevation ranges from 7,600 to 9,000 feet. The mean annual precipitation is 16 to 20 inches. The mean annual air temperature is 40 to 43 degrees F. The frost-free period is 60 to 110 days.
GEOGRAPHICALLY ASSOCIATED SOILS: These are the Nakaibito and Narbona soils. Nakaibito soils are sandy-skeletal. Narbona soils are loamy-skeletal, have sandy epipedons less than 40 inches thick, and occur on adjacent stable landslides.
DRAINAGE AND PERMEABILITY: Excessively drained; rapid runoff; rapid permeability.
USE AND VEGETATION: Zilditloi soils are used for limited timber production and livestock grazing. Present vegetation is ponderosa pine, pinyon, Rocky Mountain juniper, and scattered Douglas fir; with an understory of muttongrass, mountain muhly, true mountain mahogany, Bailey yucca, antelope bitterbrush, and Gambel oak.
DISTRIBUTION AND EXTENT: Zilditloi soils are of small extent on the Colorado Plateau in northwest New Mexico and northeast Arizona. MLRA 35; LRR-D.
MLRA SOIL SURVEY REGIONAL OFFICE (MO) RESPONSIBLE: Phoenix, Arizona
SERIES ESTABLISHED: Apache County, Arizona; Shiprock Area Soil Survey; 1993.
REMARKS: The series type location was moved to the Arizona part of the Shiprock Soil Survey Area in 1992 by New Mexico.
Diagnostic horizons and features recognized in this pedon are:
Ochric epipedon - the zone from 0 to 7 inches (A horizon)
Entisol feature - the absence of diagnostic subsurface horizons
Classified according to Soil Taxonomy, Second Edition, 1999; Keys to Soil Taxonomy, Tenth Edition, 2006.
Updated and revised for the correlation of Ft. Defiance Area (AZ715) 2/08 DWD