LOCATION TERBIES WAEstablished Series
TAXONOMIC CLASS: Loamy-skeletal, isotic, mesic Andic Haploxerepts
TYPICAL PEDON: Terbies very gravelly medial sandy loam, forested. (Colors are for moist soil unless otherwise noted. All textures are apparent field textures.)
Oi--0 to 1 inch; slightly decomposed needles, leaves, and twigs.
Oe--1 to 2 inches; moderately decomposed needles, leaves, and twigs.
A--2 to 5 inches; dark brown (10YR 4/3) very gravelly medial sandy loam, very pale brown (10YR 7/3) dry; weak very fine granular structure; soft, very friable, slightly sticky and slightly plastic; many fine and very fine roots; many fine and very fine irregular and tubular pores; 50 percent angular sandstone pebbles; moderately acid (pH 5.8); clear smooth boundary. (2 to 6 inches thick)
Bw1--5 to 13 inches; dark yellowish brown (10YR 4/6) very gravelly medial sandy loam, very pale brown (10YR 7/4) dry; weak very fine subangular blocky structure; soft, very friable, slightly sticky and slightly plastic; many fine and very fine roots; many fine and very fine irregular and tubular pores; 55 percent angular sandstone pebbles; moderately acid (pH 5.6); gradual smooth boundary.
Bw2--13 to 25 inches; dark yellowish brown (10YR 4/6) extremely gravelly medial sandy loam, very pale brown (10YR 7/4) dry; weak very fine subangular blocky structure; slightly hard, friable, slightly sticky and slightly plastic; many fine and very fine roots; many fine and very fine irregular and many very fine tubular pores; 50 percent angular sandstone pebbles and 15 percent flat sandstone fragments; moderately acid (pH 5.6); gradual smooth boundary. (Combined thickness of the Bw horizon is 10 to 20 inches.)
BC--25 to 35 inches; dark yellowish brown (10YR 4/4) extremely channery sandy loam, very pale brown (10YR 7/3) dry; weak fine and very fine subangular blocky structure; slightly hard, friable, slightly sticky and slightly plastic; common fine and very fine roots; common very fine irregular and tubular pores; 50 percent angular sandstone pebbles and 30 percent flat sandstone fragments; strongly acid (pH 5.4); gradual smooth boundary. (0 to 14 inches thick)
C--35 to 47 inches; light olive brown (2.5Y 5/4) extremely channery sandy loam, pale yellow (2.5Y 7/4) dry; massive; slightly hard, friable, slightly sticky and slightly plastic; few fine and very fine roots; common very fine irregular and tubular pores; 40 percent angular sandstone pebbles, 20 percent flat sandstone fragments, and 20 percent sandstone flagstones; strongly acid (pH 5.4); abrupt wavy boundary. (12 to 22 inches thick)
R--47 to 62 inches; fractured sandstone.
TYPE LOCATION: Clallam County, Washington; 4,000 feet west and 400 feet south of the NE corner of section 6, T.29N., R.5W.
RANGE IN CHARACTERISTICS: Depth to fractured bedrock is 40 to 60 inches. The particle size control section is 40 to 80 percent hard sandstone, siltstone or conglomerate fragments and include angular pebbles, angular cobbles, flat fragments, and flagstones and 5 to 18 percent clay. The mean annual soil temperature is 47 to 52 degrees F. The soil is dry in the moisture control section for 45 to 60 consecutive days following the summer solstice. The A and Bw horizons have acid oxalate extractable aluminum plus one-half the iron of 1 to 2 percent.
The A horizon has hue of 7.5YR or 10YR, value of 3 or 4 moist, 6 or 7 dry, and chroma of 3 or 4 moist, 2 through 4 dry. This horizon has granular or subangular blocky structure. It is slightly acid to strongly acid. It has 5 to 10 percent organic matter. Moist bulk density is 0.50 to 0.95 g/cc.
The Bw horizon has hue of 7.5YR or 10YR, value of 3 or 4 moist, 6 or 7 dry, and chroma of 4 through 6. This horizon is very gravelly medial sandy loam, extremely gravelly medial sandy loam, very gravelly medial loam, very channery medial loam or extremely channery medial loam. It is strongly acid or moderately acid. It has 1 to 5 percent organic matter. Moist bulk density is 0.90 to 1.00 g/cc.
The BC horizon has hue of 7.5YR or 10YR, value of 4 or 5 moist, 6 or 7 dry, and chroma of 4 through 6 moist, 3 through 6 dry. This horizon is very gravelly sandy loam, extremely gravelly sandy loam, extremely channery sandy loam or extremely channery loam. It is strongly acid or moderately acid.
The C horizon has hue of 7.5YR, 10YR, or 2.5Y, value of 4 or 5 moist, 6 or 7 dry, and chroma of 4 through 6. This horizon is extremely gravelly sandy loam, extremely channery sandy loam, extremely channery loam, extremely flaggy loam or extremely gravelly loamy sand. It is strongly acid or moderately acid.
COMPETING SERIES: There are currently no competing series.
GEOGRAPHIC SETTING: Terbies soils are on mountain sides at elevations of 800 to 2,00 feet. They formed in residuum and colluvium from sandstone, siltstone, or conglomerate and have slopes of 30 to 85 percent. These soils are in a mild marine climate and have cool, dry summers and cool, moist winters. The mean annual precipitation is 40 to 70 inches. The average January temperature is about 35 degrees F.; the average July temperature is about 57 degrees F.; and the mean annual temperature is about 46 degrees F. The frost free season is 150 to 180 days.
GEOGRAPHICALLY ASSOCIATED SOILS: These are the Elwha and Louella soils. Elwha soils are coarse-loamy and have a densic contact at depths of 20 to 40 inches. Louella soils are fine-loamy and have a mollic epipedon.
DRAINAGE AND PERMEABILITY: Well drained; medium runoff; moderate permeability.
USE AND VEGETATION: Timber production is the principal use. Native vegetation is predominantly Douglas fir with some grand fir, western hemlock, western red cedar and bigleaf maple. Understory species include salal, oceanspray, red huckleberry, rose, Oregon grape, twinflower, pavchystima, blackberry, western swordfern, deer fern and bedstraw.
DISTRIBUTION AND EXTENT: Central Clallam County, Washington; MLRA 2. This series is moderately extensive.
MLRA SOIL SURVEY REGIONAL OFFICE (MO) RESPONSIBLE: Portland, Oregon
SERIES ESTABLISHED: Clallam County, Washington, 1979.
REMARKS: Diagnostic horizons and other features:
Ochric epipedon
Cambic horizon - 5 to 35 inches
Andic subgroup - the zone from 2 to 25 inches has moist bulk density of 0.85 g/cc and acid oxalate aluminum plus one-half the iron of 1.2 percent.
All depths to diagnostic horizons and other features are measured from the top of the first mineral horizon.