LOCATION WHITECONE AZEstablished Series
TAXONOMIC CLASS: Fine, mixed, superactive, mesic Typic Natrargids
TYPICAL PEDON: Whitecone clay loam--on a concave footslope of an undulating plateau sloping 1 percent to the west at 5,960 feet elevation--rangeland. (Colors are for dry soil unless otherwise noted. When described, the soil was dry throughout.)
A--0 to 1 inch; pale brown (10YR 6/3) clay loam; brown (10YR 4/3) moist; moderate fine prismatic structure parting to moderate very fine subangular blocky; hard, friable, moderately sticky and moderately plastic; strongly effervescent; strongly alkaline (pH 8.7); abrupt smooth boundary. (1 to 3 inches thick)
Btn1--1 to 4 inches; brown (10YR 5/3) clay; brown (10YR 5/3) moist; moderate fine angular blocky structure; very hard, friable, very sticky and very plastic; few very fine roots; few very fine tubular pores; few distinct clay films on faces of peds; strongly alkaline (pH 8.9); clear smooth boundary. (3 to 9 inches thick)
Btn2--4 to 10 inches; brown (10YR 5/3) clay; brown (10YR 5/3) moist; moderate fine angular blocky structure; very hard, friable, very sticky and very plastic; few very fine roots; few fine tubular pores; few distinct clay films on faces of peds and lining pores; strongly effervescent; strongly alkaline (pH 8.9); clear smooth boundary. (6 to 11 inches thick)
Btn3--10 to 19 inches; brown (10YR 5/3) clay; brown (10YR 5/3) moist; moderate fine angular blocky structure; very hard, friable, very sticky and very plastic; few very fine roots; few fine tubular pores; few distinct clay films on faces of peds and lining root channels and pores; strongly effervescent; strongly alkaline (pH 8.6); clear smooth boundary. (5 to 12 inches thick)
Btn4--19 to 28 inches; brown (10YR 5/3) clay loam; brown (10YR 4/3) moist; moderate fine angular blocky structure; very hard, friable, very sticky and very plastic; few very fine roots; few very fine tubular pores; few distinct clay films on faces of peds and lining root channels and pores; strongly effervescent; strongly alkaline (pH 8.6); abrupt smooth boundary. (4 to 14 inches thick)
Btn5--28 to 39 inches; pale brown (10YR 6/3) clay loam; brown (10YR 4/3) moist; moderate medium subangular blocky structure; very hard, friable, very sticky and very plastic; few very fine roots; common fine tubular pores; few faint clay films on faces of peds; strongly effervescent; moderately alkaline (pH 8.4); clear smooth boundary. (8 to 16 inches thick)
Btn6--39 to 54 inches; pale brown (10YR 6/3) clay loam; brown (10YR 4/3) moist; moderate medium subangular blocky structure; very hard, friable, very sticky and very plastic; strongly effervescent; moderately alkaline (pH 8.2); clear smooth boundary. (12 to 16 inches thick)
Cr--54 inches; soft shale bedrock
TYPE LOCATION: Navajo County, Arizona; about 2.5 miles west/northwest of Satan Butte; Latitude 35 degrees 33 minutes 26 seconds North and Longitude 109 degrees 58 minutes 8 seconds West.
RANGE IN CHARACTERISTICS:
Soil moisture: The soil moisture control section is intermittently moist in some part from July to October and December to April. Driest during May and June. Typic Aridic soil moisture regime
Soil temperature: 53 to 56 degrees F.
Depth to base of argillic horizon: 35 inches or more
Particle-size control section weighted averages
Clay content: 35 to 50 percent
Sand content: 20 to 40 percent
Fine sand or coarser content: 5 to 15 percent
Reaction: moderately alkaline to strongly alkaline
A horizon
Hue: 5YR, 7.5YR, 10YR
Value: 5 or 6 dry, 3 or 4 moist
Chroma: 2 or 3, dry or moist
Sodicity, SAR: 4 to 12
Btn horizons
Hue: 5YR, 7.5YR, 10YR
Value: 3 to 5, dry or moist
Chroma: 3 or 4, dry or moist
Texture: clay, clay loam
Salinity, EC (dS/m): 2 to 8
Sodicity, SAR: 13 to 30
A thin Bt horizon in the upper part may be present in some pedons. Sandy clay loam textures may be present below 40 inches.
COMPETING SERIES: There are no competing series.
GEOGRAPHIC SETTING: Whitecone soils are on footslopes of undulating plateaus and low fan terraces. They formed in alluvium derived from claystone and shale. Slopes are 1 to 3 percent. Elevation ranges from 5,800 to 6,200 feet. The mean annual precipitation is 6 to 10 inches with about 45 percent falling as rain from high-intensity convective thunderstorms between July and September. The mean annual air temperature is 51 to 54 degrees F. The frost-free period is 130 to 160 days.
GEOGRAPHICALLY ASSOCIATED SOILS: This is the Redlands soils. Redlands soils are fine-loamy, have less than 13 SAR, and occur on adjacent shoulders and summits of undulating plateaus.
DRAINAGE AND PERMEABILITY: Well drained; medium surface runoff; slow permeability
USE AND VEGETATION: Whitecone soils are used for livestock grazing. Present vegetation is alkali sacaton, galleta, mound saltbush, and shadscale.
DISTRIBUTION AND EXTENT: Whitecone soils are of small extent the Colorado Plateau in northeast Arizona. MLRA 35, LRR-D
MLRA SOIL SURVEY REGIONAL OFFICE (MO) RESPONSIBLE: Phoenix, Arizona.
SERIES ESTABLISHED: Fort Defiance Area, Parts of Apache and Navajo Counties Arizona, and McKinley and San Juan Counties, New Mexico; 2008. Whitecone is a local place name. This name is coined.
REMARKS: Diagnostic horizons and features recognized in this pedon are:
Ochric epipedon - the zone from 0 to 2 inches (A horizon)
Natric horizon - the zone from 2 to 54 inches (Btn horizons)
Paralithic contact - the boundary with soft shale bedrock at 54 inches (Cr horizon)
ADDITIONAL DATA: The series type location has been sampled for full characterization by the Soil Survey Laboratory (SSL), Lincoln, NE, as soil survey sample number S86AZ-017-012; additional SSL data as sample number S86AZ-017-013
Soils classified according to Soil Taxonomy, Second Edition, 1999; Keys to Soil Taxonomy, Tenth Edition, 2006