LOCATION GUNSONE WY
Tentative Series
Rev. JGM-RJS
10/2013
GUNSONE SERIES
The Gunsone series consists of very deep, well drained soils that formed in slope alluvium over residuum derived from interbedded shale and sandstone. These soils occur on hills. Slopes are 3 to 35 percent. Mean annual precipitation is about 340 mm and mean annual air temperature is about 5.6 degrees C.
TAXONOMIC CLASS: Fine, smectitic, frigid Torrertic Haplustalfs
TYPICAL PEDON: Gunsone loam, in rangeland (colors are for dry soil unless otherwise noted).
A--0 to 12 cm; pale brown (10YR 6/3) loam, brown (10YR 4/3) moist; weak medium subangular blocky structure; soft, friable, slightly sticky and nonplastic; common very fine and few fine roots throughout; few very fine and fine dendritic tubular pores and common interstitial pores; neutral (pH 7.2); clear smooth boundary. (8 to 15 cm thick)
Btk1--12 to 32 cm; dark yellowish brown (10YR 4/4) clay loam, brown (10YR 4/3) moist; moderate medium prismatic structure parting to strong medium angular blocky; moderately hard, firm, moderately sticky and moderately plastic; few very fine and fine roots throughout; common fine and very fine dendritic tubular pores; 40 percent faint clay films on all faces of peds; finely disseminated calcium carbonate; very slightly effervescent; slightly alkaline (pH 7.4); clear smooth boundary. (10 to 27 cm thick)
Btk2--32 to 84 cm; pale brown (10YR 6/3) clay, brown (10YR 5/3) moist; moderate medium prismatic structure parting to strong medium angular blocky; moderately hard, very firm, moderately sticky and very plastic; common very fine roots between peds; few fine and common very fine dendritic tubular pores; 60 percent distinct clay films on all faces of peds; finely disseminated calcium carbonate and 4 percent medium distinct irregular carbonate masses on all faces of peds; slightly effervescent; moderately alkaline (pH 8.4); gradual smooth boundary. (30 to 60 cm thick)
BCkyz--84 to 115 cm; light yellowish brown (2.5Y 6/3) clay loam, light olive brown (2.5Y 5/3) moist; weak medium subangular blocky structure; moderately hard, firm, moderately sticky and moderately plastic; few very fine roots; few very fine irregular pores; finely disseminated calcium carbonate and 1 percent fine faint irregular carbonate masses in the matrix; 3 percent fine distinct gypsum threads in the matrix; strongly effervescent; moderately alkaline (pH 8.2); gradual wavy boundary. (10 to 35 cm thick)
C--115 to 200 cm; light yellowish brown (2.5Y 6/3) clay loam, light olive brown (2.5Y 5/3) moist; massive; moderately hard, firm, moderately sticky and moderately plastic; few very fine roots; few very fine irregular pores; 10 percent fine reddish yellow (7.5YR 6/8) mottles and 5 percent fine reddish brown (2.5YR 5/3) mottles in the matrix; finely disseminated calcium carbonate; strongly effervescent; moderately alkaline (pH 8.2).
TYPE LOCATION: Lincoln County, Wyoming; 41 degrees 50 minutes 20.88 seconds north latitude and 110 degrees 46 minutes 42.66 seconds west longitude; NAD83; UTM 518389 meters E, 4631939 meters N, zone 12.
RANGE IN CHARACTERISTICS:
Mean annual soil temperature - 5.6 to 7.8 degrees C.
Depth to top of argillic horizon - 8 to 15 cm
Depth to secondary calcium carbonate accumulation - 25 to 35 cm
Note: Some pedons may have a 2BCk horizon.
A horizon
Hue: 7.5YR or 10YR; dry or moist
Value: 4 to 6 dry; 3 or 4 moist
Chroma: 2 to 3; dry or moist
Clay content: 18 to 27 percent
Rock fragments: 0 to 2 percent gravel
Reaction: pH 7.0 to 7.5
Btk1 horizon
Hue: 7.5YR or 10YR; dry or moist
Value: 4 or 5 dry, 3 or 4 moist
Chroma: 3 or 4; dry or moist
Clay content: 27 to 35 percent
Rock fragments: 0 to 5 percent gravel
Calcium carbonate equivalent: 1 to 3 percent
Reaction: pH 7.2 to 7.8
Btk2 horizon
Hue: 7.5YR or 10YR; dry or moist
Value: 4 to 6; dry or moist
Chroma: 2 to 4; dry or moist
Texture: clay, clay loam
Clay content: 35 to 45 percent
Parafragments: 0 to 10 percent weakly cemented shale paragravel
Calcium carbonate equivalent: 2 to 5 percent
Electrical conductivity: 1 to 4 mmhos/cm
Sodium adsorption ratio: 0 to 5
Reaction: pH 8.0 to 8.6
BCkyz horizon
Hue: 7.5YR to 2.5Y; dry or moist
Value: 4 to 6; dry or moist
Chroma: 2 to 4; dry or moist
Texture: clay, clay loam
Clay content: 35 to 45 percent
Parafragments: 2 to 10 percent weakly cemented shale paragravel
Calcium carbonate equivalent: 5 to 15 percent
Gypsum: 1 to 3 percent
Electrical conductivity: 8 to 16
Sodium adsorption ratio: 3 to 12
Reaction: pH 8.0 to 8.6
C horizon
Hue: 7.5YR to 2.5Y; dry or moist
Value: 5 or 6 dry; 4 or 5 moist
Chroma: 3 or 4; dry or moist
Clay content: 27 to 40 percent
Parafragments: 0 to 30 percent weakly cemented shale paragravel
Calcium carbonate equivalent: 10 to 20 percent
Gypsum: 0 to 1 percent
Electrical conductivity: 8 to 16
Sodium adsorption ratio: 3 to 12
Reaction: pH 8.0 to 8.6
COMPETING SERIES:
Acel (MT) - do not have a horizon with salt accumulation
Bew (MT) - do not have a horizon with salt accumulation
Pylon (MT) - are moderately deep to a paralithic contact
Ulric (WY) - are moderately deep to a paralithic contact
GEOGRAPHIC SETTING:
Landform - hills
Elevation - 2,000 to 2,200 meters
Slope - 3 to 35 percent
Parent Material - slope alluvium over residuum derived from interbedded sandstone and shale
Climate - long, cold winters; short, cool summers
Mean annual precipitation - 275 to 380 mm with peak periods of precipitation occurring from March to June
Mean annual air temperature - 4.4 to 6.7 degrees C.
Frost-free period - 60 to 90
GEOGRAPHICALLY ASSOCIATED SOILS: None listed.
DRAINAGE AND PERMEABILITY: Well drained; slow permeability.
USE AND VEGETATION: Gunsone soils are primarily used for rangeland and wildlife habitat. The potential native vegetation may include early sage, Hood's phlox and thickspike wheatgrass.
DISTRIBUTION AND EXTENT: Gunsone soils are of small extent in southwestern Wyoming. MLRA - 34A.
MLRA SOIL SURVEY REGIONAL OFFICE (MO) RESPONSIBLE: Bozeman, Montana.
SERIES PROPOSED: Lincoln County, Wyoming, 1974. The series name is coined.
REMARKS: Diagnostic horizons and features recognized in this pedon are:
Ochric epipedon - 0 to 12 cm (A horizons)
Argillic horizon - 12 to 84 cm (Btk1, Btk2 horizons)
Secondary calcium carbonate accumulation - 32 to 84 cm (Btk1, Btk2, BCkyz horizons)
Particle-size control section - 12 to 62 cm (Btk1, part of Btk2 horizons)
Gunsone soils have a frigid temperature regime and an ustic moisture regime bordering on aridic.
Additional Information: The series was reclassified on 10/25/2013 from Fine, smectitic, calcareous, frigid Ustic Torriorthents to Fine, smectitic, frigid Torrertic Haplustalfs.
National Cooperative Soil Survey
U.S.A.