LOCATION YUMTHESKA AZEstablished Series
TAXONOMIC CLASS: Loamy-skeletal, mixed, superactive, mesic Lithic Calciustolls
TYPICAL PEDON: Yumtheska extremely cobbly loam - woodland. (Colors are for dry soil unless otherwise noted.)
A--0 to 2 inches; brown (10YR 5/3) extremely cobbly loam, dark brown (10YR 3/3) moist; weak thin platy structure; soft, very friable, slightly sticky and slightly plastic; common very fine roots; few fine vesicular pores; 35 percent cobble, 10 percent stones, 30 percent gravel; slightly effervescent, 5 percent calcium carbonate equivalent; slightly alkaline; clear smooth boundary. (1 to 3 inches thick)
Bw--2 to 5 inches; brown (10YR 4/3) very cobbly loam, dark brown (10YR 3/3) moist; weak medium subangular blocky structure; slightly hard, friable, slightly sticky and slightly plastic; common very fine roots; common fine tubular pores; 30 percent cobble and 15 percent gravel; strongly effervescent, 6 percent calcium carbonate equivalent; slightly alkaline; clear smooth boundary. (0 to 4 inches thick)
Bk1--5 to 14 inches; brown (10YR 4/3) very cobbly loam, dark brown (10YR 3/3) moist; weak medium subangular blocky structure; slightly hard, friable, slightly sticky and slightly plastic; many fine roots; common fine tubular pores; 35 percent cobble and 20 percent gravel with calcium carbonate pendants on undersides; violently effervescent, 24 percent calcium carbonate equivalent; moderately alkaline; clear smooth boundary. (3 to 10 inches thick)
Bk2--14 to 17 inches; brown (10YR 4/3) very cobbly loam, dark brown (10YR 3/3) moist; weak medium subangular blocky structure; slightly hard, friable, slightly sticky and slightly plastic; common medium roots; common fine tubular pores; 30 percent cobble and 15 percent gravel with calcium carbonate pendants on undersides; violently effervescent, 26 percent calcium carbonate equivalent; moderately alkaline; abrupt smooth boundary. (2 to 3 inches thick)
R--17 inches; limestone.
TYPE LOCATION: Coconino County, Arizona; on the Hualapai Indian Reservation; 50 feet west and 900 feet south of the northeast corner of Section 14, T. 30 N., R. 7 W.
RANGE IN CHARACTERISTICS:
Soil Moisture: Moist in some part of the soil moisture control section during December-March and intermittently moist during July-September. Driest during May and June. Aridic ustic soil moisture regime.
Soil Temperature: 47 to 58 degrees F.
Calcium carbonate equivalent: 15 to 40 percent
Depth to bedrock: 7 to 20 inches
Reaction: Slightly or moderately alkaline
Organic matter: Averages 1 to 5 percent in the surface
Particle size control section - Rock Fragments: 15 to 75 percent gravel and cobble; averages more than 35 percent in the particle size control section
Clay content: 15 to 30 percent; textures of loam, clay loam, or silt loam with less than 40 percent sand
A horizon
Hue: 7.5YR, 10YR
Value: 3 to 6 dry, 2.5 to 5 moist
Chroma: 2 or 3, dry or moist
Bw horizon -- not present in all pedons
Hue: 7.5YR, 10YR
Value: 3 to 5 dry, 3 moist
Chroma: 2 or 3, dry or moist
Bk horizon
Hue: 7.5YR, 10YR
Value: 2.5 to 7 dry, 3 to 5 moist
Chroma: 2 to 4, dry or moist
COMPETING SERIES: This is the
Desario (NM) and
Rudd (AZ) series.
Desario soils contain 40 to 60 percent sand in the particle size control section.
Rudd soils formed on basalt and have ustic-aridic soil moisture regime.
GEOGRAPHIC SETTING: Yumtheska soils are on hills, mountains, plateaus and mesas at elevations of 5800 to 6600 feet. These soils formed from limestone. Slopes range from 1 to 50 percent. The mean annual precipitation is 14 to 18 (20) inches. The mean annual air temperature is 45 to 56 degrees F. The frost-free period is 120 to 160 days.
GEOGRAPHICALLY ASSOCIATED SOILS: These are Disterheff, Natank, and Toqui soils. Disterheff, Natank, and Toqui soils all have fine textured argillic horizons. In addition, Disterheff soils are very deep and Natank soils are moderately deep to a lithic contact.
DRAINAGE AND PERMEABILITY: Well drained; medium runoff; moderate permeability.
USE AND VEGETATION: Yumtheska soils are used for fuelwood production, wildlife habitat and grazeable woodland. Present vegetation is Pinyon pine, Utah juniper, Stansbury cliffrose, blue grama and muttongrass.
DISTRIBUTION AND EXTENT: Northern Arizona. This series is of moderate extent. MLRA 35.
MLRA SOIL SURVEY REGIONAL OFFICE (MO) RESPONSIBLE: Phoenix, Arizona
SERIES ESTABLISHED: Coconino County, Arizona; Soil survey of Coconino County Area, Arizona, North Kaibab Part; 1991.
REMARKS: Diagnostic horizons and features recognized in this pedon are:
Mollic epipedon - The zone from 0 to 17 inches (A, Bw, Bk1, and Bk2 horizons)
Calcic horizon - The zone from 5 to 17 inches consisting of pendants on undersides of limestone fragments that exceed 5 percent by volume (Bk1, Bk2 horizons)
Lithic contact - The boundary at 17 inches (R horizon)
Classified according to Soil Taxonomy Second Edition, 1999; Keys to Soil Taxonomy Tenth Edition, 2006
ADDITIONAL DATA: Laboratory analysis by BIA Natural Resources Laboratory in Gallup, New Mexico.