LOCATION DUCKTAIL                WY

Tentative Series
Rev. JGM-RJS
10/2013

DUCKTAIL SERIES

The Ducktail series consists of very deep, well drained soils that formed in colluvium derived from limestone. These soils occur on escarpments. Slopes are 60 to 80 percent. Mean annual precipitation is about 530 mm and mean annual air temperature is about 3.3 degrees C.

TAXONOMIC CLASS: Coarse-loamy, mixed, superactive Typic Haplocryolls

TYPICAL PEDON: Ducktail loam, in forestland (colors are for dry soil unless otherwise noted).

Oi--0 to 5 cm; slightly decomposed forest litter.

A1--5 to 15 cm; dark grayish brown (10YR 4/2) loam, very dark brown (10YR 2/2) moist; weak fine granular structure; soft, very friable, nonsticky and nonplastic; common very fine and fine roots; common fine and very fine dendritic tubular pores and common fine interstitial pores; 10 percent angular limestone gravel; finely disseminated calcium carbonate; slightly effervescent; moderately alkaline (pH 8.2); clear smooth boundary. (8 to 18 cm thick)

A2--15 to 41 cm; dark grayish brown (10YR 4/2) gravelly sandy loam, very dark brown (10YR 2/2) moist; weak fine subangular blocky structure; soft, very friable, nonsticky and nonplastic; common very fine and few fine roots; common fine and few medium and coarse dendritic tubular pores and common fine interstitial pores; 15 percent angular limestone gravel; finely disseminated calcium carbonate; strongly effervescent; moderately alkaline (pH 8.4); gradual smooth boundary. (15 to 30 cm thick)

C--41 to 200 cm; light yellowish brown (2.5Y 6/3) gravelly sandy loam, olive brown (2.5Y 4/4) moist; massive; soft, very friable, slightly sticky and nonplastic; few very fine roots; few fine dendritic tubular pores and common interstitial pores; 15 percent angular limestone gravel, 5 percent angular limestone cobbles; finely disseminated calcium carbonate; violently effervescent; moderately alkaline (pH 8.4).

TYPE LOCATION: Lincoln County, Wyoming; 41 degrees 52 minutes 47.10 seconds north latitude and 110 degrees 45 minutes 48.66 seconds west longitude; NAD83; UTM 519623 meters E, 4636454 meters N, zone 12.

RANGE IN CHARACTERISTICS:
Mean annual soil temperature - 3.3 to 5.6 degrees C.
Thickness of mollic epipedon - 25 to 40

A1 horizon
Hue: 10YR or 2.5Y; dry or moist
Value: 4 or 5 dry; 2 or 3 moist
Chroma: 2 to 3; dry or moist
Clay content: 10 to 16 percent
Rock fragments: 10 to 25 percent limestone gravel
Calcium carbonate equivalent: 5 to 15 percent
Reaction: pH 7.8 to 8.4

A2 horizon
Hue: 10YR or 2.5Y; dry or moist
Value: 4 or 5 dry, 2 or 3 moist
Chroma: 2 or 3; dry or moist
Clay content: 10 to 16 percent
Rock fragments: 10 to 25 percent gravel
Calcium carbonate equivalent: 10 to 20 percent
Reaction: pH 7.8 to 8.4

C horizon
Hue: 10YR or 2.5Y; dry or moist
Value: 6 or 7 dry, 4 to 6 moist
Chroma: 3 or 4; dry or moist
Clay content: 11 to 18 percent
Rock fragments: 5 to 25 percent--5 to 20 percent limestone gravel, 0 to 5 percent limestone cobbles
Calcium carbonate equivalent: 15 to 35 percent
Reaction: pH 7.8 to 8.4

COMPETING SERIES:
There are no competing series.

GEOGRAPHIC SETTING:
Landform - escarpments
Elevation - 2,195 to 2,377 meters
Slope - 60 to 80 percent
Parent Material - colluvium derived from limestone
Climate - long, cold winters; short, cool summers; peak precipitation occurs from March to June
Mean annual precipitation - 450 to 610 mm
Mean annual air temperature - 2.2 to 4.4 degrees C.
Frost-free period - 20 to 40 days

GEOGRAPHICALLY ASSOCIATED SOILS: None listed.

DRAINAGE AND PERMEABILITY: Well drained; slow permeability.

USE AND VEGETATION: Ducktail soils are primarily used for recreation and wildlife habitat. The potential native vegetation may include Douglas fir, snowberry and Oregon grape.

DISTRIBUTION AND EXTENT: Ducktail soils are of small extent in southwestern Wyoming. MLRA - 46.

MLRA SOIL SURVEY REGIONAL OFFICE (MO) RESPONSIBLE: Bozeman, Montana.

SERIES PROPOSED: Lincoln County, Wyoming, 2012. The series name is coined.

REMARKS: Diagnostic horizons and features recognized in this pedon are:

Mollic epipedon - 5 to 41 cm (A1, A2 horizons)
Particle-size control section - 30 to 105 cm (part of A2, part of C horizons)

Ducktail soils have a cryic temperature regime and an udic moisture regime bordering on ustic.

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National Cooperative Soil Survey
U.S.A.