LOCATION DECATHON NVEstablished Series
TAXONOMIC CLASS: Clayey, smectitic, mesic, shallow Haploxeralfic Argidurids
TYPICAL PEDON: Decathon gravelly sandy clay loam--rangeland. (Colors are for dry soil unless otherwise noted.) The surface is covered with approximately 5 percent cobbles, 20 percent gravel, 5 percent mosses and lichens and 50 percent cyanobacteria. Lithology of the rock fragments is welded tuff.
A--0 to 7 cm; reddish brown (5YR 5/3) gravelly sandy clay loam, dark reddish brown (5YR 3/3) moist; strong very thick platy structure; moderately hard, very friable, moderately sticky and moderately plastic; many very fine and fine, and common medium and coarse roots; common very fine and fine vesicular pores; 30 percent gravel; slightly alkaline (pH 7.5); clear smooth boundary. (5 to 15 cm thick)
Bt--7 to 29 cm; reddish brown (5YR 4/4) clay, reddish brown (5YR 4/4) moist; strong medium subangular blocky structure; hard, very firm, very sticky and very plastic; few very fine, fine and medium roots; few very fine and fine tubular pores; many distinct clay films on faces of peds; 10 percent gravel; neutral (pH 7.3); clear smooth boundary. (13 to 30 cm thick)
Btkq--29 to 40 cm; reddish brown (5YR 5/4) sandy clay loam; reddish brown (5YR 5/4) moist; strong coarse subangular blocky structure; slightly hard, firm, moderately sticky and moderately plastic; few very fine, fine, and medium roots; few very fine and fine tubular pores; common (10 percent) coarse (5 to 20 millimeters) moderately to strongly cemented durinodes; common faint clay films on faces of peds; common (10 percent) secondary calcium carbonate concretions around rock fragments; 13 percent gravel; strongly effervescent; moderately alkaline (pH 8.2); abrupt smooth boundary. (10 to 20 cm thick)
Bkqm--40 to 53 cm; continuous strongly cemented silica and carbonate duripan with a 2 to 5 mm thick laminar cap; strong thick platy structure; very rigid; violently effervescent; abrupt smooth boundary. (10 to 38 cm thick)
2Bqk--53 to 154 cm; light reddish brown (5YR 6/4) very gravelly sandy loam, reddish brown (5YR 4/4) moist; massive; moderately hard, friable, slightly sticky and nonplastic; few very fine interstitial pores; many (30 percent) coarse (10 to 20 millimeters), very strongly cemented durinodes throughout the matrix; 20 percent calcium carbonate medium (2 to 5 millimeters) dendritic threads in matrix; 40 percent gravel; strongly effervescent; moderately alkaline (pH 8.2).
TYPE LOCATION: Lincoln County, Nevada; 150 meters northwest of the section marker; 9 meters north of the jeep trail and 3.2 kilometers west of Meadow Valley Wash; about 60 meters east and 40 meters north of the southwest corner of section 13, T. 3 N., R. 69 E.; USGS Eagle Valley Reservoir 7.5 minute topographic quadrangle; latitude 38 degrees 6 minutes 47.6 seconds N and longitude 114 degrees 12 minutes 31.6 seconds W; UTM zone 11, 744707e, 4222058n; NAD 83.
RANGE IN CHARACTERISTICS:
Soil moisture: Usually moist in winter and spring, dry in summer and fall except intermittently moist for 10 to 20 days between July and September due to convection storms; aridic soil moisture regime that borders on xeric.
Mean annual soil temperature: 8 to 11 degrees C.
Ochric epipedon thickness and depth to the argillic horizon: 5 to 15 cm.
Depth to base of argillic horizon: 28 to 50 cm.
Carbonate development stage: Stage IV.
Other features: Parent material contains a component of ashy material in the matrix.
Particle-size control section - Clay Content: Averages 35 to 50 percent.
Rock fragments: 0 to 15 percent.
A horizon
Value: 3 or 4, moist.
Chroma: 2 or 3, dry or moist.
Mineralogy: 15 to 24 percent volcanic glass in the 0.02 to 2 mm fraction and averages 0.05 to 0.09 percent Al plus 1/2Fe, extracted by ammonium oxalate.
Bt horizon
Hue1: 7.5YR or 5YR.
Value: 4 through 6, dry and 4 or 5, moist.
Chroma: 2 through 4, dry or moist.
Texture: Clay loam, sandy clay, or clay.
Reaction: Neutral through moderately alkaline.
Btkq horizon
Hue: 7.5YR or 5YR.
Value: 4 or 5, dry or moist.
Chroma: 4 or 5, dry or moist.
Clay: Averages 35 to 50 percent, some pedons containing thin sub-horizons that range to 27 percent.
Texture: Sandy clay or sandy clay loam.
Rock fragments: 0 to 15 percent, mainly gravel with a few duripan fragments.
Secondary calcium carbonate: 5 to 20 percent, usually around rock fragments or on the bottom of rock fragments.
Durinodes: 5 to 15 percent, moderately to strongly cemented, medium to very coarse (5 to 20 mm).
Effervescence: Slightly effervescent through violently effervescence.
Reaction: Slightly alkaline through strongly alkaline.
Bkqm horizon
Structure: thick and very thick, platy.
Cementation class: Strongly cemented with a laminar cap, some pedons contain thin sub-horizons that are discontinuously indurated or very strongly cemented.
Effervescence: Strongly effervescent and violently effervescent.
Reaction: Strongly alkaline or very strongly alkaline.
2Bqk horizon
Value: 4 through 6, dry or moist.
Chroma: 3 or 4, dry.
Texture: Sandy loam, loamy sand or sand.
Clay content: 2 to 12 percent.
Rock fragments: 35 to 50 percent, mainly gravel.
Structure: Massive or single grain.
Secondary calcium carbonate: 10 to 30 percent concretions around rock fragments or as dendritic threads.
Durinodes: Moderately to strongly cemented, common to many (10 to 30 percent), coarse to very coarse (10 to 30 mm).
Other features: 2Bqk horizons have a matrix that consists of lacustrine sediments of varying textures and composition that differ with changes in the depositional environment.
COMPETING SERIES: There are no competing series.
GEOGRAPHIC SETTING: Decathon soils are on summits and shoulders of fan remnants. Slopes are 2 to 15 percent. Elevations range from 1,800 to 2,000 meters. These sois formed in alluvium derived from welded tuff over lacustrine deposits. The climate is semiarid and cool, with moist winters and hot dry summers. Mean annual precipitation is 250 to 300 mm. The mean annual temperature is 7 to 10 degrees C. The frost free season is 90 to 110 days.
GEOGRAPHICALLY ASSOCIATED SOILS: These are the Basket and Buster series. Basket and Buster soils lack duripans.
DRAINAGE AND PERMEABILITY: Well drained; medium runoff; moderately slow permeability to the duripan and very slow permeability through the duripan; moderately high saturated hydraulic conductivity.
USE AND VEGETATION: Used for wildlife habitat and livestock grazing. The present vegetation is black sagebrush, buckwheat, Thurber's needlegrass, muttongrass, Indian ricegrass, blue grama, antelope bitterbrush, cliffrose, and invaded Utah juniper and singleleaf pinyon pine. This pedon has been correlated to Ecological Site Description R028AY035NV, Shallow Clay Loam 10-12 P.Z.
DISTRIBUTION AND EXTENT: East central Nevada. Decathon soils are moderately extensive. MRLA 28A.
MLRA SOIL SURVEY REGIONAL OFFICE (MO) RESPONSIBLE: Phoenix, Arizona.
SERIES ESTABLISHED: Lincoln County (Meadow Valley Area), Nevada, 1971.
REMARKS: Diagnostic horizons and features recognized in this pedon are:
Ochric epipedon - The zone from the surface to 7 cm (A horizon).
Argillic horizon - The zone from 7 to 40 cm (Bt and Btkq horizons).
Duripan - The zone from 40 to 53 cm (Bkqm horizon).
Durinodes - The zone from 53 to 154 cm (2Bqk horizon).
Particle-size control section - The zone from 7 to 40 cm (Bt and Btkq horizons).
ADDITIONAL DATA: The type was moved 10/2008 to better reflect the series concept.
Decathon soils were formerly classified as Fine-loamy, mixed, superactive, frigid Xeric Argidurids.
Pedon ID: 06NV613002-BAG