LOCATION RADNOR MTEstablished Series
TAXONOMIC CLASS: Fine-silty, mixed, superactive, frigid Argiaquic Argialbolls
TYPICAL PEDON: Radnor silty clay loam, in a cultivated field, 1 percent slope (colors are for dry soil unless otherwise noted).
Ap-- 0 to 5 inches; gray (10YR 6/1) silty clay loam, dark gray (10YR 4/1) moist; weak fine and very fine granular structure and many fine plate-like chips of the original lighter colored medium platy A2 that is mixed with AO and the A1 layers; slightly calcareous, which likely is due to calcareous overwash from spoil bank of a drainage ditch in the general vicinity.
A2-- 5 to 14 inches; white (10YR 8/1) silty clay loam; gray (2.5Y 6/1) moist; moderate thick platy structure; slightly hard, slightly firm; noncalcareous; clear lower boundary. (5 to 10 inches thick)
B2g-- 14 to 30 inches; white (2.5Y 8/1) silty clay loam, gray (2.5Y 5/1) moist; common faint to prominent fine brown and yellow mottles; weak medium blocky structure; hard, firm; noncalcareous; clear lower boundary. (8 to 20 inches thick)
Cg-- 30 to 40+ inches; white (5Y 8/1) thinly stratified silt loam and silty clay loam, gray (5Y 6/1) moist with common prominent fine and faint medium brown and yellowish mottles; hard, firm; alkaline to slightly calcareous.
TYPE LOCATION: Flathead County, Montana; SE 1/4 of the SE 1/4 Section 28, Township 31 N., Range. 21 W.
RANGE IN CHARACTERISTICS:
Soil temperature - 39 to 45 degrees F.
Depth to seasonal high water table - 12 to 36 inches
Ap horizon
Texture, less than 2 mm: silt loam or silty clay loam
Clay content: 18 to 30 percent
Rock fragments:
Reaction: pH 6.1 to 6.5
A2 horizon
Texture, less than 2 mm: silty clay loam
Clay content: 27 to 35 percent
Rock fragments:
Reaction: pH 6.1 to 6.5
B2g horizon
Texture, less than 2 mm: silty clay loam
Clay content: 27 to 35 percent
Reaction: pH 6.1 to 7.3
Cg horizon
Texture, less than 2 mm: silt loam or silty clay loam
Clay content: 10 to 27 percent
Calcium carbonate equivalent: 1 to 5 percent
Reaction: pH 6.1 to 7.8
COMPETING SERIES: There are no competing series.
GEOGRAPHIC SETTING: The Radnor soils are on nearly level valley floors where stream channels are not deeply entrenched, and shallow concave drainage swales and closed depressions and elevated terraces that lie below higher land. Slopes are 0 to 3 percent slopes. These soils formed in glacial lake and stream sediments derived from argillite, quartzite and dolomitic limestone from the Belt formation. Mean annual precipitation is 15 to 19 inches. Mean annual temperature is 39 to 45 degrees F. The frost-free period is 105 to 125 days.
GEOGRAPHICALLY ASSOCIATED SOILS: None listed.
DRAINAGE AND PERMEABILITY: Poor to very poor drainage; slow permeability.
USE AND VEGETATION: Radnor soils are used mainly for forestry, wildlife, and brushy pasture. Some areas are flooded by beaver dams. Where cleared and the drainage improved, fair yields of oats, tame grass, and Alsike clover hay are obtained. Some of the improved pastures support a fair to good sod of bluegrass and white Dutch clover. Potential native vegetation is mainly conifers, chiefly spruce and certain of the firs, willow, alder, sedge, coarse grasses, and mosses.
DISTRIBUTION AND EXTENT: Radnor soils are inextensive in western Montana,
MLRA SOIL SURVEY REGIONAL OFFICE (MO) RESPONSIBLE: Bozeman, Montana.
SERIES ESTABLISHED: Upper Flathead Valley Area, Montana, 1957. The name is taken from a small town in Lincoln County, Montana, near where the soils were first defined.
REMARKS: Soil Interpretations Record: MT0628.
On 3/4/2009 this description is being entered for the first time into the OSD files. Although it was established in 1957 it has never been in an electronic form. Except for the classification, this series has not been reviewed or updated.