LOCATION TENEX MTEstablished Series
TAXONOMIC CLASS: Loamy-skeletal, mixed, superactive Spodic Dystrocryepts
TYPICAL PEDON: Tenex cobbly loam - forest
(Colors are for dry soil unless otherwise noted.)
01 1 1/2 Ù Black partially decomposed organic layer composed of conifer needles and leaves of other forest plants; slightly cemented when dry.
02 l"-O--Black, highly decomposed organic layer from the forest vegetation; slightly cemented when dry.
A2 0-1/2"--Light gray (lOYR 7/1) sandy loam, gray (lOYR 5/1) moist; abrupt broken boundary. (O to 2 inches thick)
Bl 1/2 -4"--Pale brown (lOYR 6/3) cobbly loam, dark brown (lOYR 4/3) moist; weak fine subangular blocky structure; soft, very friable, nonsticky, nonplastic; many roots; 25 percent coarse fragments by volume; very strongly acid (pH 5.0); clear wavy boundary. (2 to 6 inches thick)
B21ir 4 Ù Light yellowish brown (lOYR 6/4) cobbly light clay loam, dark yellowish brown (lOYR 4/4) moist; moderate fine and medium blocky structure; slightly hard, friable, slightly sticky, slightly plastic; common roots; 30 percent coarse fragments by volume; very strongly acid (pH 5.0); gradual wavy boundary. (4 to 8 inches thick)
B22ir 11-23"--Light yellowish brown (lOYR 6/4) very cobbly light clay loam, yellowish brown (lOYR 5/4) moist; moderate fine and medium subangular blocky structure; hard, friable, slightly sticky, slightly plastic; common roots; coarse fragments are 45 percent of volume; very strongly acid (pH 5.0); gradual wavy boundary. (10 to 15 inches thick)
IIB3 23-51"--Light yellowish brown (lOYR 6/4) very cobbly sandy loam, yellowish brown (lOYR 5/4) moist; weak fine blocky structure; soft, very friable, nonsticky, slightly plastic; few roots; very pale brown (lOYR 6/3) coats; 70 percent coarse fragments by volume; very strongly acid (pH 5.0); gradual wavy boundary. (25 to 30 inches thick)
IIC2 51-70"--Light yellowish brown (lOYR 6/4) with coatings of very pale brown (lOYR 7/3) very cobbly sandy loam, yellowish brown (lOYR 5/4) moist; massive; slightly hard, friable, nonsticky, slightly plastic; few roots; 65 percent coarse fragments by volume; pH 5.5 with small areas of high chroma (probably limestone remnants) having pH of 8.0.
Type Location: Glacier County, Montana, on Fox Creek, 2,640 feet north and 1,188 feet east of SW corner of section 20, T.34N., R.13W.
Range in Characteristics: Solum thickness ranges from 45 to 56 inches. The glacial till mantle s usually very thick but dark colored shale, sandstone, or limestone may occur at depths of 5 or 6 feet. Coarse fragments in the upper 2 to 3 feet range from 20 to 40 percent increasing to 60 to 70 percent of volume below 2 to 3 feet. Coarse fragments range from gravel to stone size. Average summer soil temperature ranges from 42 to 45 degrees F. Mean annual soil temperature ranges from 36 to 38 degrees F. The soil is usually moist but it is dry in most years for less than 60 days in the upper 30 inches in July and August. Late summer and fall rain and snow usually moisten the soil again before cold weather. This soil is generally frozen for a brief period in November and December before the snow accumulates and insulates the soil. The control section ranges from loam to light clay loam with 36 to 60 percent coarse fragments. The A2 horizon is discontinuous but comprises 50 percent of the area beneath the O horizon in every pedon. It is light gray (lOYR 6/1 or 7/1) dry and gray to very dark gray (lOYR 5/1 to lOYR 3/2) moist. The Bir horizon has hue of lOYR or 7.5YR, value of 5 or 6 dry and 4 or 5 moist and chroma of 3 or 4. It is loam or light clay loam with very little clay accumulation evident except around limestone fragments. It has weak to moderate granular or blocky structure. The C horizon ranges from very cobbly sandy loam to very cobbly loam.
Tenex Serles
2
Competing Series and their Differentiae: These are the Brody, Craddock, Evaro, Holloway, Homestead, Huckleberry, and Wessel series. Brody and Huckleberry soils have hard rock strata between depths of 20 to 40 inches. Craddock, Evaro, Holloway and Wessel soils have B horizons developed in a mantle less than 20 inches thick and high in volcanic glass, also, Craddock, Evaro and Holloway soils have a buried light gray or white A2 horizon. Wessel soils have limestone bedrock between depths of 20 and 40 inches. Homestead solls have less than 20 percent clay in the 10- to 40-inch control section and their B horizon is developed in a loess mantle.
Setting: Tenex soils are on smooth or dissected slopes mantled with glacial deposits from valley glaciers in the Rocky Mountains. Elevations range from 4,800 to 4,800 feet. Hard red and green argillite, quartzite and some brown sandstone and gray lime6tone make up the lithology of the coarse fraction. Commonly these soils occupy the slopes below the high benches occupied by Sherburne soils. Long cold winters interrupted by frequent Chinook winds and short relatively warm summers characterize the climate. Estimated mean air temperatures are: annual 37 degrees F., winter 20 degrees F. and summer 55 degrees F. Annual precipitation ranges from 20 to 30 inches, about half occurs between November 1 and May 1 as snow and sleet. Snow depths of five feet are common.
Principal Associated Soils: These are the Letarg, Loberg, Mikesell, Sherburne and Whitore soils. Letarg and Loberg soils have albic and argillic horizons. Mikesell soils have an albic horizon and a clayey argillic horizon. Sherburne soils have a clayey argillic horizon. Whitore soils have a calcic horizon.
Drainage and Permeability: Well-drained; moderate to rapid permeability.
Use and Vegetation: The major use is woodland. Woodland grazing is limited. Lodgepole pine, alpine fir and Engelmann spruce are tÙe major species. Arnica, huckleberry and pÙrola are common understory species. Alder and beargrass occur in the understory on some areas.
Distribution and Extent: Tenex soils are inextensive, occurring in the major valleys on the east side of Glacier National Park in western Montana.
Series Established: Glacier County (Blackfeet Reservation-Cut Bank Area), Montana, 1969.
Remarks: Tenex soils were formerly classified as Brown Podzolic soils.
OSED scanned by NSSQA. Last revised by state on 1/71.