LOCATION SERENE WAEstablished Series
TAXONOMIC CLASS: Sandy-skeletal, isotic Andic Haplocryods
TYPICAL PEDON: Serene gravelly ashy sandy loam - forested (Color is for moist soil unless otherwise stated. All textures are apparent field textures).
Oi--0 to 2 inches; slightly decomposed forest litter, needles, twigs, bark, and moss. (1 to 3 inches thick)
E--2 to 4 inches; brown (7.5YR 5/2) ashy loamy sand (volcanic ash) pinkish gray (7.5YR 6/2) dry; weak fine granular structure; soft, very friable, nonsticky and nonplastic, weakly smeary; many very fine roots; many very fine and fine interstitial pores; NaF pH 9.2; very strongly acid (pH 5.0); abrupt wavy boundary. (1 to 4 inches thick)
Bhs1--4 to 5 inches; dark brown (7.5YR 3/2) gravelly ashy sandy loam, dark brown (7.5YR 3/4) dry; moderate coarse granular structure; slightly hard, very friable, nonsticky and nonplastic, weakly smeary; many very fine and fine roots; many very fine and fine interstitial pores; 20 percent gravel and hard cinders; NaF pH 12.0+; moderately acid (pH 6.0); gradual wavy boundary. (1 to 4 inches thick)
Bhs2--5 to 8 inches; dark reddish brown (5YR 3/3) very gravelly ashy sandy loam, strong brown (7.5YR 4/6) dry; moderate medium subangular blocky structure; slightly hard, very friable, nonsticky and nonplastic, moderately smeary; many very fine and fine and few medium and coarse roots; many very fine and fine interstitial pores; 40 percent gravel and hard cinders; NaF pH 12.0+; moderately acid (pH 5.6); gradual wavy boundary. (2 to 5 inches thick)
Bs--8 to 16 inches; dark yellowish brown (10YR 4/6) very gravelly ashy loamy sand, yellowish brown (10YR 5/6) dry, with dark reddish brown (5YR 3/2) stains on coarse fragments; massive; hard, friable, nonsticky and nonplastic, weakly smeary; common fine and medium roots; many fine and medium interstitial pores; 45 percent gravel, 5 percent cobbles; NaF pH 11.5; moderately acid (pH 5.8); abrupt wavy boundary. (2 to 10 inches thick)
2BC--16 to 32 inches; olive brown (2.5Y 4/4) extremely cobbly coarse sand, pale yellow (2.5Y 7/4) dry; massive, slightly hard, friable, nonsticky and nonplastic; many fine and medium interstitial pores; 20 percent gravel, 45 percent cobbles; NaF pH 11.5; moderately acid (pH 5.8); gradual smooth boundary. (0 to 22 inches thick)
2Cr--32 inches; grayish brown (2.5Y 5/2) highly weathered granodiorite; light brownish gray (2.5Y 6/2) dry; this material can be cut with a spade with difficulty and textures as very gravelly coarse sand; 70 percent hard gravel; moderately acid (pH 5.8).
TYPE LOCATION: Snoqualmie Pass Area, King County, Washington; in upper Hansen Creek drainage, about 100 feet south of spur off Forest Service road number 2291A; 1,980 feet west and 1,100 feet north of the southeast corner of section 21, T. 22 N., R. 10 E.
RANGE IN CHARACTERISTICS: Depth to paralithic contact is 20 to 40 inches. The upper 7 to 14 inches of the soil has an estimated moist bulk density of 0.70 to 1.00 g/cc, volcanic glass content of 30 to 60 percent, acid-oxalate extractable aluminum plus one-half of the acid-oxalate extractable iron of more than 2.0 percent and 15-bar water retention of 5 to 12 percent. Rock fragments, including hard cinders, in the control section, average from 35 to 70 percent. The mean annual soil temperature is 37 to 42 degrees F. The soils have a udic soil moisture regime.
The E horizon has hue of 5YR or 7.5YR, value of 5 through 7 moist and 6 to 8 dry, and chroma of 0 through 2 moist or dry. There is tonguing of this horizon into the B horizon in some pedons. It is moderately acid to very strongly acid.
The Bhs horizon has hue of 2.5YR, 5YR, or 7.5YR moist and 5YR or 7.5YR dry; value of 2 through 5 moist, 3 to 6 dry, and chroma of 2 through 4 moist, 4 through 6 dry. There is up to 15 percent black organic staining up to 2mm in diameter in some pedons. Texture is ashy sandy loam, or ashy loam modified by from 15 to 55 percent coarse fragments including hard cinders. Structure is weakly to strongly expressed and is granular, subangular blocky, or angular blocky. It is slightly acid to very strongly acid.
The Bs horizon has hue of 7.5YR, 5YR or 10YR, value of 4 or 5 moist, 5 or 6 dry, and chroma of 4 through 6 moist and dry. Dark stains are lacking in some pedons. Texture is ashy loamy sand or ashy sandy loam. Coarse fragments range from 30 to 60 percent. It is slightly acid to strongly acid.
The 2BC horizon has hue of 10YR or 2.5Y, value of 4 through 7 moist and dry, and chroma of 2 through 6 moist and dry. Rock fragments are angular and granitic and range from 40 to 75 percent. Reaction is slightly acid to strongly acid.
A 2C horizon may be present in some profiles, and has chroma of 4 or 6 moist or dry. It is very gravelly coarse sand or extremely cobbly loamy sand. It is slightly acid to strongly acid.
COMPETING SERIES: These are the Altapeak, Index and Skipeak series. Altapeak, Index and Skipeak soils are more than 40 inches deep to bedrock.
GEOGRAPHIC SETTING: Serene soils are on mountain ridge crests and sideslopes 3,000 to 6,000 feet in elevation. Slopes range from 8 to 90 percent. Serene soils formed in a thin mantle of volcanic ash over residuum and colluvium from granitic and low-grade metamorphic rocks including granite, granodiorite, slate, and phyllite. The climate is maritime influenced with cold, wet winters and cool, moist summers. The mean January temperature is about 27 degrees F, the mean July temperature is about 58 degrees F, mean annual air temperature is about 40 degrees F. Average annual precipitation is 70 to 130 inches, with a considerable portion of this being in the form of snow. Growing season (28 degrees F) is 90 to 130 days.
GEOGRAPHICALLY ASSOCIATED SOILS: These are the Haywire, Index, Klapatche, Nagrom, Nimue, Playco, Reggad, Shuksan, and Spukwush soils and the competing Altapeak soils. Index, Playco, and Spukwush soils are greater than 40 inches deep. Haywire, Nagrom, Playco, and Shuksan soils are loamy- skeletal. Reggad soils are fragmental and have a histic epipedon. Spukwush soils are ashy over loamy. Shuksan soils have a paralithic contact with dense glacial till at 20 to 40 inches. Klapatche soils have a Bhs horizon with a ratio of free iron to carbon of less than 0.2.
DRAINAGE AND PERMEABILITY: Well drained, moderate permeability in the upper part and rapid in the lower part.
USE AND VEGETATION: Used for timber production, watershed and wildlife habitat. Native vegetation is Pacific silver fir, noble fir, western hemlock, Alaska cedar, mountain hemlock, and Douglas-fir, with an understory of huckleberry, trailing blackberry, rusty menziesia, twinflower, bunchberry dogwood, deer fern, princes' pine, lupine, salal, Cascade azalea, common beargrass, and moss.
DISTRIBUTION AND EXTENT: Central Cascade Mountains in Washington; MLRA 3. Series is of moderate extent.
MLRA SOIL SURVEY REGIONAL OFFICE (MO) RESPONSIBLE: Portland, Oregon
SERIES ESTABLISHED: Snoqualmie Pass Area, King County, Washington, 1986.
REMARKS: Diagnostic horizons and features recognized in this pedon are an albic horizon from the mineral surface to 2 inches, a spodic horizon from 4 to 16 inches, and a paralithic contact at 32 inches. Hard consolidated bedrock commonly occurs 35 to 40 inches below the paralithic contact
ADDITIONAL DATA: Partial laboratory data are available. NSSL Lincoln, Nebr. Sample Nos. 807091-807095.