LOCATION RYELL MT
Established Series
Rev. DHF-JJU-JCK
04/2021
RYELL SERIES
The Ryell series consists of very deep, well drained soils that formed in alluvium. These soils are on flood plains, flood-plain steps, drainageways, and stream terraces. Slopes are 0 to 4 percent. Mean annual precipitation is about 305 mm. Mean annual air temperature is about 5.5 degrees C.
TAXONOMIC CLASS: Coarse-loamy over sandy or sandy-skeletal, mixed, superactive, calcareous, frigid Aridic Ustifluvents
TYPICAL PEDON: Ryell loam, in cropland (colors are for dry soil unless otherwise noted).
Ap--0 to 20 cm; light brownish gray (10YR 6/2) loam, dark grayish brown (10YR 4/2) moist; moderate very fine and fine granular structure; slightly hard, very friable, slightly sticky and slightly plastic; many very fine and fine roots; strongly effervescent; moderately alkaline (pH 8.4); abrupt wavy boundary. (5 to 25 cm thick)
C1--20 to 71 cm; light brownish gray (10YR 6/2) very fine sandy loam with thin strata of silt loam, dark grayish brown (10YR 4/2) moist; massive; slightly hard, very friable, slightly sticky and slightly plastic; many very fine and fine roots; many very fine and fine pores; strongly effervescent; moderately alkaline (pH 8.4); gradual wavy boundary. (30 to 66 cm thick)
2C2--71 to 152 cm; light brownish gray (10YR 6/2) extremely gravelly loamy sand, dark grayish brown (10YR 4/2) moist; single grain; loose; 65 percent gravel; strongly effervescent; moderately alkaline (pH 8.4).
TYPE LOCATION: Cascade County, Montana; 549 meters east and 320 meters south of the northwest corner of sec. 36, T. 12N, R. 1W.
RANGE IN CHARACTERISTICS:
Mean annual soil temperature - 4.4 to 8.0 degrees C
Depth to lithologic discontinuity - 46 to 100 cm
Ap horizon
Hue: 10YR or 2.5Y; dry or moist
Value: 4 to 6 dry; 2 to 5 moist
Chroma: 2 or 3; dry or moist
Texture: loam, sandy loam, very fine sandy loam, fine sandy loam or silt loam
Clay content: 10 to 27 percent
Rock fragments: 0 to 15 percent gravel
Calcium carbonate equivalent: 0 to 10 percent
Effervescence: none to strongly
Electrical conductivity: 0 to 2 mmhos/cm
Reaction: pH 6.6 to 8.4
C1 horizon
Hue: 10YR or 2.5Y; dry or moist
Value: 5 to 7 dry; 4 to 6 moist
Chroma: 2 to 4; dry or moist
Texture: very fine sandy loam, loamy very fine sand, and loam consisting of very fine sand, with thin strata of silt loam and/or fine sandy loam
Clay content: 10 to 18 percent
Rock fragments: 0 to 15 percent gravel
Calcium carbonate equivalent: 3 to 15 percent
Effervescence: slight to violently
Electrical conductivity: 0 to 2 mmhos/cm
Reaction: pH 7.8 to 8.4
2C2 horizon
Hue: 10YR, 2.5Y, or 5Y; dry or moist
Value: 5 to 7 dry; 4 to 6 moist
Chroma: 2 to 4; dry or moist
Texture: sand or loamy sand
Clay content: 0 to 10 percent
Rock fragments: 35 to 75 percent--35 to 60 percent gravel, 0 to 15 percent cobbles
Calcium carbonate equivalent: 0 to 15 percent
Effervescence: none to violently
Electrical conductivity: 0 to 4 mmhos/cm
Reaction: pH 6.6 to 8.4
COMPETING SERIES: There are no competing series.
GEOGRAPHIC SETTING:
Landform - flood plains, flood-plain steps, drainageways and stream terraces
Elevation - 610 to 1,829 meters
Slope - 0 to 4 percent
Parent material - alluvium
Climate - long, cold winters; moist springs; warm summers
Mean annual precipitation - 254 to 356 mm
Mean annual air temperature - 3.3 to 7.2 degrees C
Frost-free period - 90 to 135 days
GEOGRAPHICALLY ASSOCIATED SOILS: None listed.
DRAINAGE AND PERMEABILITY: Well drained; moderate permeability above the 2C2 horizon and rapid in the 2C2 horizon.
USE AND VEGETATION: Ryell soils are used for irrigated and nonirrigated crops and for range. The potential native vegetation is mainly bluebunch wheatgrass, green needlegrass, western wheatgrass, needleandthread, forbs and shrubs. Some areas have low density stands of cottonwood trees.
DISTRIBUTION AND EXTENT: Ryell soils are of moderate extent in Montana. MLRAs - 43B, 44B, 46, 52, 58A.
MLRA SOIL SURVEY REGIONAL OFFICE (MO) RESPONSIBLE: Bozeman, Montana.
SERIES ESTABLISHED: Cascade County, Montana, 1975.
REMARKS: Diagnostic horizons and features recognized in this pedon are:
Ochric epipedon - from 0 to 20 cm (Ap horizon)
Lithologic discontinuity - at 71 cm (2C2 horizon)
Particle-size control section - from 25 to 100 cm (part of the C1 and 2C2 horizons)
Ryell soils have a frigid temperature regime and an ustic moisture regime bordering on aridic.
ADDITIONAL DATA: Soil interpretations records - MT0208, MT0877.
National Cooperative Soil Survey
U.S.A.