LOCATION OWENSPRING ID+MT
Established Series
REV. KTS-RJS-EMM
04/2013
OWENSPRING SERIES
The Owenspring series consists of moderately deep, well drained soils that formed in slope alluvium, colluvium and slide deposits over residuum derived from interbedded sedimentary rock. These soils occur on hills, mountains, escarpments, structural benches, and landslides. Slopes range from 4 to 45 percent. The mean annual precipitation is about 430 mm, and the mean annual air temperature is about 3 degrees C.
TAXONOMIC CLASS: Fine-loamy, mixed, superactive Ustic Argicryolls
TYPICAL PEDON: Owenspring loam, in rangeland on a 10 percent slope at an elevation of 2070 meters (colors are for dry soil unless otherwise noted).
A--0 to 9 cm; dark grayish brown (10YR 4/2) loam, very dark grayish brown (10YR 3/2) moist; moderate fine granular structure; slightly hard, friable, slightly sticky and slightly plastic; many very fine, fine and medium roots; 10 percent gravel; neutral (pH 7.2); clear smooth boundary. (7 to 15 cm thick)
Bt--9 to 26 cm; brown (10YR 4/3) gravelly clay loam, dark brown (10YR 3/3) moist; strong medium subangular blocky structure; hard, firm, moderately sticky and moderately plastic; many very fine, fine and medium roots; many very fine and fine irregular pores; 20 percent distinct patchy clay films on faces of peds; 17 percent gravel; slightly alkaline (pH 7.4); gradual wavy boundary. (15 to 30 cm thick)
Btk--26 to 51 cm; brown (10YR 5/3), clay loam, brown (10YR 4/3) moist; strong medium and coarse subangular blocky structure; hard, firm, moderately sticky and moderately plastic; common very fine and fine roots; common very fine and fine dendritic tubular pores; 20 percent distinct patchy clay films on faces of peds; 10 percent gravel; finely disseminated calcium carbonate and 10 percent fine and medium patchy soft masses and threads of calcium carbonate; strongly effervescent; moderately alkaline (pH 8.0); gradual wavy boundary. (15 to 30 cm thick)
Bk--51 to 69 cm; very pale brown (10YR 7/3), paragravelly silty clay loam, pale brown (10YR 6/3) moist; weak medium subangular blocky structure; slightly hard, friable, moderately sticky and very plastic; few very fine and fine roots; common very fine dendritic tubular pores; 30 percent paragravel; finely disseminated calcium carbonate and 30 percent fine and medium patchy soft masses and threads of calcium carbonate; violently effervescent; moderately alkaline (pH 8.2); gradual wavy boundary. (15 to 60 cm thick)
Cr--69 to 152 cm; semi-consolidated interbedded sedimentary rock.
TYPE LOCATION: Clark County, Idaho; located about 50 meters east and 630 meters north of the southwest corner of sec. 5, T. 13N, R. 36E; Paul Reservoir topographic quadrangle; UTM 12T, 399894e, 4926001n, NAD 83.
RANGE IN CHARACTERISTICS:
Mean annual soil temperature: 2 to 5 degrees C.
Mollic epipedon thickness: 18 to 38 cm
Depth to top of argillic horizon - 7 to 15 cm
Depth to secondary calcium carbonates: 20 to 40 cm
Depth to a paralithic contact - 50 to 100 cm
Particle-size control section (weighted average) - 25 to 35 percent clay
A horizon
Value: 3 to 5 dry; 2 or 3 moist
Chroma: 2 or 3; dry or moist
Clay content: 18 to 26 percent
Rock fragments: 0 to 15 percent gravel
Reaction: pH 6.8 to 7.4
Bt horizon
Value: 3 to 5 dry; 2 or 3 moist
Chroma: 2 or 3; dry or moist
Texture: loam, clay loam or silty clay loam
Clay content: 24 to 35 percent
Rock fragments: 0 to 20 percent gravel
Reaction: pH 6.8 to 7.6
Btk horizon
Hue: 10YR or 2.5Y; dry or moist
Value: 4 to 6; dry or moist
Chroma: 2 or 3; dry or moist
Texture: loam, clay loam or silty clay loam
Clay content: 24 to 35 percent
Rock fragments: 0 to 20 percent gravel
Calcium carbonate equivalent: 1 to 10 percent
Reaction: pH 7.9 to 8.4
Bk horizon
Hue: 10YR or 2.5Y; dry or moist
Value: 5 to 7 dry; 4, 5 or 6 moist
Chroma: 2 or 3; dry or moist
Texture: loam, clay loam, or silty clay loam
Clay content: 20 to 35 percent
Rock fragments: 0 to 35 percent gravel and/or paragravel
Calcium carbonate equivalent: 5 to 15 percent
Reaction: pH 7.9 to 8.4
COMPETING SERIES:
Amsden (WY) - are very deep
Barbarela (MT) - does not have secondary calcium carbonate accumulation
Beaveridge (WY) - are very deep
Beavmid (WY) - are very deep
Cific (WY) - have a lithologic discontinuity
Coldspring (CO) - are deep to a lithic contact
Croftshaw (NM) - are very deep
Dewville (CO) - are very deep
Gelkie (CO) - are very deep
Highrye (MT) - are deep to a paralithic contact
Hooligan (MT) - does not have secondary calcium carbonate accumulation
Inchau (WY) - does not have secondary calcium carbonate accumulation
Kezar (CO) - are moderately deep to a lithic contact
Leavitt (WY) - are very deep
Lucky (CO) - are moderately deep to a lithic contact
Lymanson (WY) - does not have silty clay loam textures in the profile
Miracle (CO) - are moderately deep to a lithic contact
Monaberg (MT) - are very deep
Passcreek (WY) - are moderately deep to a lithic contact
Rainbolt (WY) - does not have a Btk horizon
Tripit (WY) - does not have secondary calcium carbonate accumulation
Wellsville (CO) - are very deep
Woosley (WY) - are moderately deep to a lithic contact
Youga (CO) - are deep or very deep
Zade (MT) - does not have secondary calcium carbonate accumulation
GEOGRAPHIC SETTING:
Landform - hills, mountains, escarpments, structural benches, and landslides
Elevation - 1980 to 2700 meters
Slope - 4 to 45 percent
Parent material - slope alluvium, colluvium and slide deposits over residuum derived from interbedded sedimentary rock
Climate - long, cold winters; moist springs; short warm summers
Mean annual precipitation - 380 to 600 mm
Mean annual air temperature - 1 to 4 degrees C.
Frost-free period - 50 to 70 days
GEOGRAPHICALLY ASSOCIATED SOILS: None listed.
DRAINAGE AND PERMEABILITY: Well drained; moderate permeability.
USE AND VEGETATION: Owenspring soils are primarily used for rangeland and wildlife habitat. The potential native vegetation is mainly Idaho fescue, bluebunch wheatgrass, prairie junegrass, mountain brome, Columbia needlegrass, rabbitbrush, grey horsebrush, shrubby cinquefoil, threetip sagebrush, mountain big sagebrush, lupine, pussytoes, sticky geranium, sedum (stoneseed), Western yarrow, milkvetch, and other miscellaneous forbs and halfshrubs.
DISTRIBUTION AND EXTENT: Owenspring soils are of small extent in southwestern Montana. MLRA - 43B.
MLRA SOIL SURVEY REGIONAL OFFICE (MO) RESPONSIBLE: Bozeman, Montana.
SERIES ESTABLISHED: Horse Prairie-South Valley Area - Part of Beaverhead County, Montana, 2011; proposed in Clark County, Idaho, 2011.
REMARKS: Diagnostic horizons and features recognized in this pedon are:
Mollic epipedon - from 0 to 26 cm (A, Bt horizons)
Argillic Horizon - from 9 to 51 cm (Bt, Btk horizons)
Secondary calcium carbonate accumulation - from 26 to 69 cm (Btk, Bk horizons)
Particle-size control section - from 9 to 51 cm (Bt, Btk horizons)
Owenspring soils have a cryic temperature regime and an ustic moisture regime.
Taxonomic version: Eleventh Edition, 2010.
National Cooperative Soil Survey
U.S.A.