LOCATION WILAHA AZEstablished Series
TAXONOMIC CLASS: Fine-loamy over fragmental, mixed, superactive, mesic Vitritorrandic Argiustolls
TYPICAL PEDON: Wilaha gravelly loam - grazeable woodland. (Colors are for dry soil unless otherwise noted.)
A1--0 to 2 inches; reddish brown (5YR 5/3) gravelly loam, dark reddish brown (5YR 3/3) moist; moderate very fine granular structure; soft, very friable, nonsticky and nonplastic; few fine roots; many very fine interstitial pores; 20 percent gravel-size cinders; slightly alkaline (pH 7.5); abrupt smooth boundary. (1 to 5 inches thick)
A2--2 to 5 inches; reddish brown (5YR 4/3) gravelly loam, dark reddish brown (5YR 3/3) moist; weak medium subangular blocky structure parting to weak fine granular; slightly hard, friable, slightly sticky and nonplastic; common fine roots; common very fine interstitial pores and few very fine tubular pores; 25 percent gravel-size cinders; slightly alkaline (pH 7.6); gradual wavy boundary. (2 to 4 inches thick)
Bt1--5 to 8 inches; reddish brown (5YR 5/3) gravelly clay loam, dark reddish brown (5YR 3/3) moist; weak medium subangular blocky structure; slightly hard, friable, slightly sticky and slightly plastic; common fine tubular pores; very few faint clay films lining tubular pores; 25 percent gravel-size cinders; slightly alkaline (pH 7.6); gradual wavy boundary. (3 to 6 inches thick)
Bt2--8 to 14 inches; reddish brown (5YR 5/4) gravelly clay loam, dark reddish brown (5YR 3/4) moist; weak medium subangular blocky structure; hard, firm, moderately sticky and moderately plastic; common very fine roots; few fine tubular pores; few distinct clay films on faces of peds; 25 percent gravel-size cinders; strongly effervescent; moderately alkaline (pH 7.9); gradual wavy boundary. (3 to 6 inches thick)
Bk--14 to 17 inches; pinkish gray (7.5YR 7/2) very gravelly loam, brown (7.5YR 5/4) moist; massive; few very fine roots; 45 percent gravel-size cinders; strongly effervescent; moderately alkaline (pH 7.9); abrupt wavy boundary (1 to 4 inches thick)
2C--17 to 60 inches; cinders; massive; few coarse roots; few filaments and soft masses of calcium carbonates and coatings of calcium carbonates on cinders in the upper part.
TYPE LOCATION: Coconino County, Arizona; about 54 miles southeast of Flagstaff, in the NW 1/4SE 1/4 of sec. 5, T. 16 N., R. 14 E.
RANGE IN CHARACTERISTICS:
Mollic epipedon: 7 to 15 inches thick and may include part of the Bt
Soil moisture: Intermittently moist in some part of the SMCS from July to September and December to February. Aridic ustic moisture regime.
Soil temperature: 50 - 55 degrees F.
Rock fragments: 10 to 35 percent gravel-size cinders or cobbles
Depth to cinders: 10 to 24 inches
A horizons
Hue: 5YR or 7.5YR
Value: 3 to 5, dry or moist
Chroma: 2 or 3, dry or moist
Organic matter: 1 percent, decreases regularly
Reaction: Neutral to moderately alkaline
Bt horizons
Hue: 2.5YR to 7.5YR
Value: 3 to 5, dry or moist
Chroma: 2 to 4, dry or moist
Texture: gravelly clay loam and clay loam(28 - 35 percent clay)
Reaction: Slightly alkaline or moderately alkaline
Ck horizon
Hue: 5YR or 7.5YR
Value: 6 to 8 dry, 5 or 6 moist
Chroma: 2 to 4, dry or moist
Texture: very gravelly loam (10 - 25 percent clay)
Reaction: Slightly alkaline or moderately alkaline
COMPETING SERIES: There are no competing series.
GEOGRAPHIC SETTING: Wilaha soils are on fan terraces and hills at elevations of 5,600 to 7,200 feet. They formed in slope alluvium derived from pyroclastics. Slopes range from 0 to 60 percent. The mean annual precipitation ranges from 12 to 18 inches, occurring as thunderstorms in July, August and September and as rain and snow in winter. The mean annual temperature ranges from 49 to 54 degrees F. The frost-free period ranges from 120 to 170 days.
GEOGRAPHICALLY ASSOCIATED SOILS: These are the Aut, Springerville, Thunder bird, Wukoki, and Ziegler soils. Aut, Springerville, and Wukoki do not have argillic horizons. Thunderbird and Ziegler soils contain more than 35 percent clay in the control section.
DRAINAGE AND PERMEABILITY: Well drained. Runoff is slow to medium. Permeability is moderately slow.
USE AND VEGETATION: These soils are used as grazeable woodland, fuelwood and wildlife habitat. Native Vegetation is mainly pinyon pine and juniper with understory of blue grama, galleta, threeawn, black grama, and winterfat.
DISTRIBUTION AND EXTENT: North central Arizona. The series is moderately extensive. MLRA is 35 & 39.
MLRA SOIL SURVEY REGIONAL OFFICE (MO) RESPONSIBLE: Phoenix, Arizona
SERIES ESTABLISHED: Coconino County Area, Arizona, Central Part; 1980. The name is from a railroad site.
REMARKS: Diagnostic horizons and features recognized in this pedon are:
Mollic epipedon - the zone from 0 to 8 inches (A & Bt1 horizons)
Argillic horizon - the zone from 5 to 14 inches (Bt horizons)
Classified according to Soil Taxonomy Second Edition, 1999; Keys to Soil Taxonomy Tenth Edition, 2006.
Pronounced Wil'-a-ha.