LOCATION TENAS              WA
Established Series
Rev. WAS/ARH/RJE
10/2001

TENAS SERIES


The Tenas series consists of moderately deep, well drained soils on mountain side slopes and ridges at elevations of 3,000 to 6,000 feet. They formed in volcanic ash over andesite residuum. The mean annual precipitation is 25 to 35 inches. The mean annual temperature is 38 to 42 degrees F. The frost free period is 80 to 100 days.

TAXONOMIC CLASS: Fine-loamy, isotic Vitrandic Haplocryolls

TYPICAL PEDON: Tenas ashy loam, grassland. (Colors are for dry soil unless otherwise stated.)

0e--0 to 1 inch; partially decomposed forest litter.

A1--1 to 7 inches; very dark gray (10YR 3/1) ashy loam, black (10YR 2/1) moist; weak fine granular structure; soft, friable, nonsticky, nonplastic; many fine roots; 10 percent gravel; slightly acid (pH 6.4); clear wavy boundary. (5 to 8 inches thick)

A2--7 to 13 inches; very dark brown (10YR 2/2) gravelly ashy loam, black (10YR 2/1) moist; weak fine granular structure; soft, friable, nonsticky, nonplastic; many fine roots; 20 percent gravel; slightly acid (pH 6.1); clear wavy boundary. (5 to 8 inches thick)

2Bw1--13 to 15 inches; dark reddish gray (5YR 4/2) gravelly clay loam, dark reddish brown (5YR 2/2) moist; moderate medium and fine subangular blocky structure; slightly hard, firm, moderately sticky, slightly plastic; few fine roots; 30 percent gravel and stones; moderately acid (pH 5.8); clear smooth boundary. (2 to 3 inches thick)

2Bw2--15 to 31 inches; reddish gray (5YR 5/2) clay loam, dark reddish brown (5YR 3/2) moist; moderate medium and fine subangular blocky structure; slightly hard, firm, moderately sticky, moderately plastic; few fine roots; 35 percent stones; moderately acid (pH 5.9); abrupt smooth boundary. (8 to 18 inches thick)

2R--31 inches; fractured andesite bedrock.

TYPE LOCATION: Ferry County, Washington; on forest road to Bodic Mountain Lookout; uphill from road on first switchback east going down mountain from lookout; NW1/4 NW1/4 section 6, T.38N., R.32E.

RANGE IN CHARACTERISTICS: The mean annual soil temperature at a depth of 20 inches ranges from 38 to 42 degrees F., and the mean summer temperature is less than 47 degrees F. The upper part of the control section is dominated by volcanic ash. The remainder of the control section has mixed mineralogy and has 20 to 30 percent clay. The control section averages 15 to 35 percent coarse fragments. The mollic epipedon ranges from 10 to 18 inches thick. The depth to bedrock ranges from 20 to 36 inches. These soils are usually moist, but are dry in all parts between depths of 4 and 12 inches for 60 to 90 consecutive days.

The A horizon has value of 2 through 4 dry and 2 or 3 moist, and chroma of 1 or 2 dry or moist. It has weak granular or blocky structure and is neutral or slightly acid.

The 2Bw horizon has hue of 5YR or 7.5YR, value of 3 through 5 dry and 2 through 4 moist, and chroma of of 2 or 3 dry or moist. It is clay loam and may be gravelly. This horizon is moderately acid to strongly acid.

COMPETING SERIES: These are the Longswamp series and the similar Edds, Gahee, Growden, Leonardo, and Toroda series. The Longswamp soils are very deep. Edds, Growden, Leonardo, and Toroda soils lack bedrock within a depth of 40 inches. Gahee soils lack mollic and umbric epipedons.

GEOGRAPHIC SETTING: Tenas soils are on gently sloping to steep mountain side slopes and ridges at elevations of 3,000 to 6,000 feet. They formed in volcanic ash over andesite residuum. These soils occur in a cold, subhumid climate. The mean annual precipitation is 25 to 35 inches, occurring mostly as snow. The mean annual temperature is 38 to 42 degrees F. The frost free period is 80 to 100 days.

GEOGRAPHICALLY ASSOCIATED SOILS: These are the competing Edds, Leonard, and Growden soils.

DRAINAGE AND PERMEABILITY: Well drained; medium runoff; moderate permeability.

USE AND VEGETATION: Grazing and wildlife browse. Bluebunch wheatgrass, Idaho fescue, Sandberg bluegrass, pinegrass, lupiner, yarrow, pussytoes, buckwheat, and wild strawberry are the principal plants.

DISTRIBUTION AND EXTENT: Northeastern Washington. Series is of small extent.

MLRA SOIL SURVEY REGIONAL OFFICE (MO) RESPONSIBLE: Bozeman, Montana

SERIES ESTABLISHED: Ferry County (North Ferry Area), Washington, 1971.

REMARKS: This draft reflects a change in classification from Medial over loamy, mixed, Typic Vitrandepts to Fine-loamy, isotic Vitrandic Haplocryolls. This change is based on Soil Taxonomy 2nd Ed

Diagnostic horizons and features recognized in this pedon are:
Mollic epipedon; the zone from 1 to 13 inches (Ap and A horizons)
Cambic horizon; the zone from 13 inches to 31 inches (2Bw horizon)
Lithic contact at 31 inches.


National Cooperative Soil Survey
U.S.A.