LOCATION RIMTON WY
Established Series
Rev. AJC-MCS-KLS
03/2023
RIMTON SERIES
The Rimton series consists of moderately deep, well drained soils that formed in medium textured alluvium and residuum, on moderately steep and steep north and east facing hill and mountain slopes. The mean annual precipitation is about 460 mm. The mean annual air temperature is about 4 degrees C.
TAXONOMIC CLASS: Fine-loamy, mixed, superactive Ustollic Glossocryalfs
TYPICAL PEDON: Rimton loam -on a northeast facing slope of 18 percent under aspen. (Colors are for dry soil unless otherwise stated.)
Oi--0 to 3 cm; undecomposed organic matter; principally leaves, twigs, bark, and the fleshy remains of grasses; abrupt wavy boundary. (3 to 8 cm thick)
Oe--3 to 8 cm; partially decomposed organic matter; abrupt smooth boundary. (0 to 5 cm thick)
A--8 to 28 cm; dark grayish brown (10YR 4/2) loam, very dark grayish brown (10YR 3/2) moist; moderate fine granular structure; soft, very friable, slightly plastic, slightly sticky; common fine roots; common fine pores; neutral (pH 6.6); clear smooth boundary. (13 to 23 cm thick)
E--28 to 41 cm; light brownish gray (10YR 6/2) very fine sandy loam, grayish brown (10YR 5/2) moist; weak fine platy structure that parts to moderate fine granules; soft, very friable, nonplastic, nonsticky; common fine and medium roots; common fine and medium pores: neutral (pH 6.8); gradual wavy boundary. (8 to 20 cm thick)
E/B--41 to 64 cm; light brownish gray (10YR 6/2) sandy clay loam, grayish brown (10YR 5/2) moist surrounding smaller areas of grayish brown (10YR 5/2) dry and dark grayish brown (10YR 4/2) moist; moderate medium and fine subangular blocky structure; slightly hard, very friable, slightly plastic, slightly sticky; few distinct clay films on the vertical faces of peds within the B portion of this horizon; neutral ( pH 6.8); gradual wavy boundary. (8 to 30 cm thick)
Bt1--64 to 84 cm; grayish brown (10YR 5/2) sandy clay loam, dark grayish brown (10YR 4/2) moist; moderate coarse and medium subangular blocky structure; slightly hard, very friable, slightly plastic, slightly sticky; common distinct clay films on vertical ped faces; common fine and medium roots; common fine and medium pores; neutral (pH 6.8); gradual wavy boundary. (13 to 90 cm thick)
Bt2--84 to 99 cm; yellowish brown (10YR 5/4) sandy clay loam, dark yellowish brown (10YR 4/4) moist; weak medium subangular blocky structure; hard, firm, slightly plastic, slightly sticky; common distinct clay films on vertical ped faces; neutral (pH 6.8); gradual wavy boundary. (8 to 20 cm thick)
Cr--99 cm; noncalcareous soft sandy shale.
TYPE LOCATION: Carbon County, Wyoming; southwest quarter of the southwest quarter of sec. 29, T. 17 N., R. 88 W.
RANGE IN CHARACTERISTICS:
Mean annual soil temperature--2 to 7 degrees C
Mean summer soil temperature--7 to 13 degrees C
Depth to paralithic contact--50 to 100 cm
These soils are normally noncalcareous throughout but some pedons have thin discontinuous subhorizons that are calcareous that occur just above the paralithic contact.
Rock fragment content--0 to 15 percent. Some pedons have a thin stone line with up to 50 percent rock fragments just above the paralithic contact.
A horizon
Hue--10YR or 2.5Y
Value--3 through 5 dry, 2 or 3 moist
Chroma--1 through 3
Texture--sandy loam, fine sandy loam, or loam
E horizon
Hue--10YR or 2.5Y,
Value--5 or 6 dry, 3 through 5 moist
Chroma--2 through 4
Texture--fine sandy loam or very fine sandy loam
E/B horizon
Hue--10YR or 2.5Y
Value--5 or 6 dry, 3 through 5 moist
Chroma--2 through 4
This horizon typically has more than one color and exhibits tonguing and interfingering.
Texture--sandy loam or sandy clay loam, with more than 35 percent fine sand or coarser
Bt horizon
Hue--10YR or 7.5YR
Value--4 or 5 dry, 3 or 4 moist
Chroma--2 through 6
Clay content--18 to 35 percent
Silt content--5 to 25 percent
Sand content--55 to 70 percent, with more than 35 percent being fine or coarser sand.
Some pedons have a thin transitional horizon between the base of the argillic horizon and the paralithic contact.
COMPETING SERIES: Other series in the same subgroup and family include the
Amesmont (T),
Beardall,
Bramard,
Dunlatop,
Hub,
Nisula, Stringham,
Swapps,
Telcher,
Ula, and
Wix series. The Bramard, Dunlatop, Hub, Nisula,
Stringam,and Telcher series are deep or very deep to bedrock. The Beardall and Swapps series have a lithic contact above 100 cm. The Amesmont and Ula soils allow hues redder than 7.5YR in the Bt horizon. The Wix series does not have a E/B horizon.
GEOGRAPHIC SETTING:
Landform--moderately steep to steep north and east facing hill and mountain slopes
Elevation--2375 to 2900 meters
Slope--10 to 40 percent
Parent material--alluvium and residuum derived from noncalcareous shale and sandstone
Mean annual precipitation--460 mm with peak periods of precipitation occurring in the spring and early summer months
Mean annual air temperature--3 degrees C
Mean summer air temperature--13 degrees C
Frost-free period--less than 60 days
GEOGRAPHICALLY ASSOCIATED SOILS: None listed.
DRAINAGE AND PERMEABILITY: Well drained. Runoff is medium to rapid. Permeability is moderate.
USE AND VEGETATION: These soils are used mostly for wildlife habitat and livestock grazing. Native vegetation includes aspen, Columbia needlegrass, and Oregon grape.
DISTRIBUTION AND EXTENT: Rimton soils are of small extent in southeastern Wyoming; MLRAs 48A and 49.
SOIL SURVEY REGIONAL OFFICE (SSRO) RESPONSIBLE: Bozeman, Montana
SERIES PROPOSED: Sage Creek area, Carbon County, Wyoming, 1972. Series name is a coined name.
REMARKS: Diagnostic horizons and features recognized in this pedon are:
Ochric epipedon--8 to 28 cm (A horizon)
Albic horizon--28 to 41cm (E horizon)
Argillic horizon--64 to 99 (Bt1 and Bt2 horizons)
Depth to paralithic contact--99 cm to bedrock (Cr horizon)
Particle-size control section--64 to 99 (Bt1 and Bt2 horizons)
Converted to metric and O horizons were updated to start at zero. Competing series section was not updated. 02/2023
National Cooperative Soil Survey
U.S.A.