LOCATION REEDPOINT MTEstablished Series
TAXONOMIC CLASS: Loamy-skeletal, mixed, superactive, frigid Aridic Lithic Haplustolls
TYPICAL PEDON: Reedpoint very channery loam, in rangeland. (Colors are for dry soil unless otherwise noted)
A--0 to 5 inches; brown (10YR 5/3) very channery loam, dark brown (10YR 3/3) moist; weak fine granular structure; soft, very friable, slightly sticky and slightly plastic; common very fine and fine roots; many fine pores; 38 percent sandstone channers; neutral (pH 7.2); abrupt smooth boundary. (4 to 9 inches thick)
R--5 inches or more; hard, noncalcareous sandstone.
TYPE LOCATION: Sweet Grass County, Montana; 2,300 feet west and 2,800 feet south of the NE corner of sec. 36, T. 3 N., R. 18 E.
RANGE IN CHARACTERISTICS:
Soil temperature - 42 to 47 degrees F.
Heating degree days - (normals 1941-70) 7331 days.
Cooling degree days - (normals 1941-70) 379 days.
Moisture control section - from 4 inches to bedrock; moist April through June, dry some or all parts July through mid September, and moist some or all parts mid September through October. The soil has an Aridic-Ustic moisture regime.
Mollic epipedon thickness - 4 to 9 inches.
Rock fragments - 35 to 60 percent sandstone pebbles and channers.
Depth to bedrock - 4 to 10 inches.
Thin B horizons, less than 3 inches thick, having higher moist values, prismatic or blocky structure and slight clay increases are allowed.
A horizon - Hue: 7.5YR or 10YR
Value: 4 or 5 dry, 2 or 3 moist
Chroma: 2 or 3
Texture: loam, fine sandy loam, silt loam, clay loam
Clay content: 10 to 35 percent
Fine and coarser sand content: less than 35 percent
Rock fragments: 35 to 60 percent--35 to 45 percent channers, 0 to 15 percent flagstones
Reaction: pH 6.6 to 7.8
COMPETING SERIES:
Duffymont (CO) - dry in all parts of the moisture control section for 45 days after July first; 10 to 20 inches deep to a lithic contact.
Moonset (UT) - are shallow to shale bedrock.
GEOGRAPHIC SETTING:
Landform - bedrock-floored plains; escarpments; hills; mountains.
Elevation - 3,700 to 5,500 feet.
Slope- 0 to 75 percent.
Parent material - residuum or colluvium derived from sandstone.
Climate - long, cold winters; moist springs; warm summers.
Mean annual precipitation - 10 to 14 inches, more than 70 percent of which falls in spring or early summer.
Mean annual air temperature - 39 to 45 degrees F.
Frost-free period - 90 to 130 days.
GEOGRAPHICALLY ASSOCIATED SOILS: These are the Ethridge, Evanston, Rentsac and Sixbeacon soils.
DRAINAGE AND PERMEABILITY: Well drained; moderate permeability.
USE AND VEGETATION: Reedpoint soils are used for rangeland. The potential native vegetation is bluebunch wheatgrass, western wheatgrass, needleandthread, eriogonum, phlox, and other perennial grasses and forbs.
DISTRIBUTION AND EXTENT: This series is of limited extent; found mainly in the sedimentary uplands of south-central Montana.
MLRA SOIL SURVEY REGIONAL OFFICE (MO) RESPONSIBLE: Denver, Colorado
SERIES ESTABLISHED: Sweet Grass County, Montana, 2000.
REMARKS: Soil interpretation record: MT1374. Diagnostic horizons and features recognized in this pedon are: mollic epipedon - from the soil surface to 5 inches (A horizon); particle-size control section - from the soil surface to a depth of 5 inches (A horizon); lithic contact - at a depth of 5 inches (R horizon). Reedpoint soils have an ustic moisture regime that borders on aridic.