LOCATION EAGLECONE               ID

Established Series
Rev. DRG/RG/MD/WGH
08/2021

EAGLECONE SERIES

The Eaglecone series consists of deep, well drained soils that formed in loess and eolian sand over basalt. Eaglecone soils are on smooth and convex positions on lava flows on lava fields. Slopes range from 1 to 8 percent. The mean annual air temperature is about 6 degrees C and the mean annual precipitation is about 355 mm.

TAXONOMIC CLASS: Loamy-skeletal, mixed, superactive, frigid Typic Calcixerolls

TYPICAL PEDON: Eaglecone very cobbly very fine sandy loam on a west facing linear 1 percent slope, under shrubs at an elevation of 1745 meters. When described on August 3, 2006, the soil was dry throughout. (Colors are for dry soil unless otherwise noted.)

Akq1-- 0 to 8 cm; dark brown (10YR 3/3) very cobbly very fine sandy loam, very dark brown (10YR 2/2) moist; weak fine granular structure; slightly hard, very friable, nonsticky and nonplastic; many very fine and common fine roots; many very fine irregular and few fine tubular pores; calcium carbonate and silica coats about 1 mm thick on bottoms of rock fragments, slightly effervescent; 5 percent gravel, 45 percent cobbles; neutral (pH 6.9); gradual wavy boundary.

Akq2-- 8 to 15 cm; dark brown (10YR 3/3) extremely cobbly loam, very dark grayish brown (10YR 3/2) moist; weak fine and medium subangular blocky structure; soft, very friable, nonsticky and nonplastic; many very fine and common fine roots; many very fine interstitial pores; calcium carbonate and silica coats 1 to 2 mm thick on bottoms of rock fragments, slightly effervescent; 20 percent gravel, 45 percent cobbles; neutral (pH7.1); gradual wavy boundary. ( combined thickness of the Akq horizons ranges from 8 to 25 cm)

Bkq1-- 15 to 31 cm; brown (10YR 4/3) extremely cobbly loam, dark brown (10YR 3/3) moist; weak very fine and fine subangular blocky structure; soft, very friable, nonsticky and nonplastic; many very fine, common medium and fine roots; few fine tubular and many very fine interstitial pores; calcium carbonate and silica coats 1 to 3 mm thick surrounding entire rock fragments; finely disseminated calcium carbonate in the matrix, few fine and medium very weakly cemented irregular calcium carbonate masses in the matrix; slightly effervescent (10 percent calcium carbonate); 2 percent gravel, 75 percent cobbles; slightly alkaline (pH 7.7); clear wavy boundary. (2 to 20 cm thick)

Bkq2-- 31 to 71 cm; brown (10YR 5/3) extremely cobbly loam, dark yellowish brown (10YR 3/4) moist; weak medium subangular blocky structure; soft, very friable, nonsticky and nonplastic; many very fine, common fine and medium roots; common very fine and fine tubular pores; calcium carbonate and silica coats less than 1 mm thick surrounding entire rock fragments; finely disseminated calcium carbonate in matrix, common fine, medium and coarse extremely hard calcium carbonate nodules in the matrix; violently effervescent (20 percent calcium carbonate); 5 percent gravel, 50 percent cobbles, 15 percent stones; moderately alkaline (pH 7.9); gradual wavy boundary.

Bkq3-- 71 to 109 cm; light brownish gray (10YR 6/2) extremely stony sandy loam, brown (10YR 4/3) moist; massive; loose, nonsticky and nonplastic; many very fine, common fine and medium roots; common very fine tubular pores; calcium carbonate and silica coats 1 to 3 mm thick surrounding entire rock fragments, finely disseminated calcium carbonate in matrix, few fine, medium and coarse extremely hard calcium carbonate nodules in the matrix; violently effervescent (25 percent calcium carbonate); 5 percent gravel, 30 percent cobbles, 40 percent stones; moderately alkaline (pH 8.1); gradual wavy boundary.

Bkq4-- 109 to 152 cm; light gray (10YR 7/2) extremely cobbly loamy fine sand, light olive brown (2.5Y 5/3) moist; massive; loose, nonsticky and nonplastic; common very fine, fine and medium roots; many very fine interstitial pores; calcium carbonate and silica coats 1 to 3 mm thick surrounding entire rock fragments, finely disseminated calcium carbonate in matrix, few medium and coarse indurated calcium carbonate nodules in the matrix; violently effervescent (30 percent calcium carbonate); 15 percent gravel including nodules, 45 percent cobbles, 25 percent stones; moderately alkaline (pH 8.2) (combined thickness of the Bkq2, Bkq3 and Bkq4 horizons 106 to 121 cm)

2R-- 152 cm; vesicular basalt

TYPE LOCATION: Clark County, Idaho about 11.8 kilometers east and 6.3 kilometers north of Dubois, Idaho; about 495 meters west and 142 meters south of the northeast corner of sec. 3, T.10N. R.37E.; USGS Dubois NE, Idaho topographic quadrangle; latitude 44 degrees, 13 minutes, 47.1 seconds N. and longitude 112 degrees, 4 minutes and 48.6 seconds W.; NAD 83

RANGE IN CHARACTERISTICS:

Mean annual soil temperature: 6 to 7.5 degrees C. (Frigid soil temperature regime)
Mean summer soil temperature: 17 to 21 degrees C.
Thickness of mollic epipedon: 25 to 43 cm
Depth to calcic horizon: 8 to 25 cm
Particle-size control section clay content: Total 12 to 20 percent; carbonate 2 to 5 percent; noncarbonate 7 to 18 percent
Particle-size control section rock fragments: averages 50 to 75 percent
Control section calcium carbonate equivalent: 20 to 40 percent
Depth to lithic contact: 100 to 152 cm.

Akq and where present Ap and A horizons
Value: 3 or 4 dry, 2 or 3 moist
Chroma 2 or 3 moist or dry
Rock fragment content: Total 0 to 65 percent; 0 to 20 percent gravel, 0 to 45 percent cobbles and 0 to 15 percent stones
Clay content: Total 10 to 18 percent
Reaction: neutral to slightly alkaline

Bkq1 and where present Bk horizon
Value: 4 or 5 dry
Rock fragment content: Total 35 to 80 percent; 2 to 60 percent gravel, 5 to 75 percent cobbles and 0 to 15 percent stones
Fine-earth texture: L or FSL
Clay content: Total 12 to 20 percent; 2 to 4 percent carbonate and 10 to 20 percent noncarbonate
Reaction: Neutral to moderately alkaline
Calcium carbonate equivalent: 10 to 20 percent
Other features: Some pedons may have up to 35 percent weakly cemented cicada nodules

Bkq2 to Bkq4 horizons
Hue: 10YR or 2.5Y moist
Value: 5 through 8 dry, 3 through 6 moist
Chroma: 2 or 3 dry, 3 or 4 moist
Rock fragment content: Total 60 to 90 percent; 5 to 50 percent gravel, 15 to 70 cobbles and 1 to 40 stones
Fine-earth texture: LFS, FSL, SL, and L
Clay content: Total 10 to 22 percent; 2 to 5 percent carbonate and 7 to 18 percent noncarbonate
Reaction: Neutral to moderately alkaline
Calcium carbonate equivalent: 20 to 50 percent
Other features: Some pedons may have a discontinuous laminar cap less than 1 mm thick

COMPETING SERIES: These are Bezzant, Cedarhill, Dennot, Georgecanyon and Pyrenees series. The Bezzant, Cedarhill, Dennot, Georgecanyon soils are very deep to bedrock. The Pyrenees soil is moderately deep to bedrock.

GEOGRAPHIC SETTING:
Landscape: Lava fields
Landform: Lava flow
Elevation: 1585 to 1768 meters
Slope: 1 to 8 percent
Parent Material: Loess and eolian sand over basalt
Mean annual precipitation: 305 to 406 mm
Mean annual air temperature: 5 to 7 degrees C.
Frost-free period: 70 to 95 days

GEOGRAPHICALLY ASSOCIATED SOILS: These are Blacknoll, Jacoby, Jipper, Nayrib and Hotspot series. Blacknoll soils are moderately deep to bedrock. Jacoby soils have less than 35 percent coarse fragments in the particle size control section. Jipper soils have a mollic epipedon over 50 cm. thick Nayrib soils are very shallow to bedrock. Hotspot soils are shallow to bedrock.

DRAINAGE AND SATURATED HYDRAULIC CONDUCTIVITY:
Drainage class: Well drained
Runoff: Low
Saturated hydraulic conductivity: High in the upper part of the subsoil to very high in the lower part of the subsoil

USE AND VEGETATION:
Major uses: Rangeland and wildlife habitat
Range Site: R011BY011ID and R013BY001ID
Dominant native vegetation: Threetip sagebrush, mountain big sagebrush, antelope bitterbrush, bluebunch wheatgrass, needleandthread, indian ricegrass, prairie junegrass, buckwheat, horsebrush, prickly pear cactus, bluegrass, rabbit brush, bushy birdsbeak, lupine, and western wheatgrass

DISTRIBUTION AND EXTENT: Southeastern Idaho; MLRA 11, and 13. The series is of moderate extent.

SOIL SURVEY REGIONAL OFFICE (SSRO) RESPONSIBLE: Portland, Oregon

SERIES ESTABLISHED: Clark County, Idaho, 2018.

REMARKS:
Diagnostic horizons and features in this pedon include:
Mollic epipedon: the zone from 0 to 31 cm
Calcic horizon: the zone from 15 to a depth of 152 cm
Particle size control section: the zone from 25 to 100 cm
Soil moisture regime: Xeric
Soil temperature regime: Frigid
The 2008 description moves the type location and reclassification of the series from Aridic to Typic subgroup.

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National Cooperative Soil Survey
U.S.A.