LOCATION RIVERSIDE MT
Established Series
Rev. EMR/JMS/JCK
11/2014
RIVERSIDE SERIES
The Riverside series consists of very deep, excessively drained soils that formed in alluvium and colluvium. These soils are on fan remnants, eroded fan remnants, hills, and escarpments. Slopes are 0 to 40 percent. Mean annual precipitation is about 368 millimeters and mean annual air temperature is about 6 degrees C.
TAXONOMIC CLASS: Sandy-skeletal, mixed, frigid Entic Haplustolls
TYPICAL PEDON: Riverside gravelly sandy loam, in rangeland on a 6 percent slope at 1,023 meters elevation (colors are for dry soil unless otherwise indicated).
A--0 to 25 cm; grayish brown (10YR 5/2) gravelly sandy loam, very dark grayish brown (10YR 3/2) moist; weak medium granular structure; very friable, soft, nonsticky and nonplastic; many fine and common medium roots; many fine interstitial pores; 15 percent gravel, 5 percent cobbles; neutral (pH 7.2); clear smooth boundary. (18 to 38 cm thick)
BC--25 to 32 cm; pale brown (10YR 6/3) gravelly sandy loam, brown (10YR 4/3) moist; weak fine subangular blocky structure; very friable, soft, nonsticky and nonplastic; common fine and medium roots; many fine interstitial pores; 20 percent gravel, 10 percent cobbles; neutral (pH 7.2); gradual wavy boundary. (0 to 14 cm thick)
C1--32 to 64 cm; pale brown (10YR 6/3) very gravelly loamy coarse sand, brown (10YR 4/3) moist; single grain; loose, nonsticky and nonplastic; few fine roots; common fine interstitial pores; 40 percent gravel, 10 percent cobbles; neutral (pH 7.0); gradual smooth boundary.
C2--64 to 150 cm; light yellowish brown (2.5Y 6/3) extremely gravelly coarse sand, olive brown (2.5Y 4/3) moist; single grain; loose, nonsticky and nonplastic; few fine roots; common fine interstitial pores; 55 percent gravel, 10 percent cobbles; neutral (pH 7.0).
TYPE LOCATION: Bing topographic quadrangle, Ravalli County, Montana; 360 meters south and 265 meters west of the NE corner of section 15, T. 8 N., R. 20 W. UTM Zone 11: 724472e, 5148707n, NAD 83.
RANGE IN CHARACTERISTICS:
Mean annual soil temperature - 5 to 8 degrees C
Mollic epipedon thickness - 18 to 38 cm
Depth to sandy-skeletal material - 18 to 52 cm
A horizon
Value: 4 or 5 dry; 2 or 3 moist
Chroma: 2 or 3 dry or moist
Texture: sandy loam, fine sandy loam, or loam
Clay content: 6 to 22 percent
Rock fragments: 0 to 35 percent--0 to 35 percent gravel, 0 to 20 percent cobbles, 0 to 5 percent stones
Reaction: pH 6.6 to 7.8
BC horizon
Value: 6 or 7 dry; 4 or 5 moist
Chroma: 2, 3, or 4 dry or moist
Texture: sandy loam or loamy sand
Clay content: 2 to 15 percent
Rock fragments: 15 to 45 percent--10 to 35 percent gravel, 0 to 25 percent cobbles
Reaction: pH 6.6 to 7.8
C horizon(s)
Hue: 10YR or 2.5Y
Value: 6 or 7 dry; 4, 5, or 6 moist
Chroma: 2, 3, or 4 dry or moist
Texture: loamy coarse sand, coarse sand, loamy sand, or sand
Clay content: 0 to 11 percent
Rock fragments: 35 to 80 percent--15 to 70 percent gravel, 5 to 45 percent cobbles and stones
Reaction: pH 6.6 to 7.8
COMPETING SERIES:
Corbly (MT) - have a horizon of secondary calcium carbonate accumulation
Dominic (MT) - have an epipedon with more than 35 percent rock fragments
Wabek (ND+MT SD) - have a horizon of secondary calcium carbonate accumulation; are slightly alkaline to strongly alkaline in the particle-size control section
Wheelbarrow (MT) - are 50 to 100 cm deep to a paralithic contact
GEOGRAPHIC SETTING:
Landform - fan remnants, eroded fan remnants, and escarpments
Elevation - 970 to 1,790 meters
Slope - 0 to 40 percent
Parent material - alluvium and colluvium
Climate - long, cold winters; moist springs; warm summers
Mean annual precipitation - 305 to 432 millimeters, much of which falls as snow and as spring rain
Mean annual air temperature - 4 to 7 degrees centigrade
Frost-free period - 80 to 120 days
GEOGRAPHICALLY ASSOCIATED SOILS: None listed.
DRAINAGE AND PERMEABILITY: Excessively drained; moderately rapid permeability to a depth of 30 cm and very rapid below.
USE AND VEGETATION: Riverside soils are used mainly for dryland pasture; vegetation is chiefly mixed grasses, such as bluebunch wheatgrass and needle and thread.
DISTRIBUTION AND EXTENT: Riverside soils are of small extent in the valleys of western Montana. MLRA 43B and 44A.
MLRA SOIL SURVEY REGIONAL OFFICE (MO) RESPONSIBLE: Bozeman, Montana.
SERIES ESTABLISHED: Ravalli County (Bitterroot Valley Soil Survey), Montana, 1952.
REMARKS: Diagnostic horizons and features recognized in this pedon are:
Mollic epipedon - from 0 to 25 cm (A horizon)
Particle-size control section - from 25 to 100 cm (part of BC and C horizons)
Riverside soils have a frigid temperature regime and an ustic moisture regime.
The type location has been moved and re-described to current description standards.
National Cooperative Soil Survey
U.S.A.