LOCATION GETCHELL WAEstablished Series
TAXONOMIC CLASS: Medial, amorphic Aquic Haplocryands
TYPICAL PEDON: Getchell silt loam - forested. (Colors are for moist soil unless otherwise noted. All textures are apparent field textures.)
O1--1 1/2 to 1 inch; leaves, needles and twigs.
O2--1 inch to 0; decomposed mat of needles, twigs and leaves.
A--0 to 2 inches; black (10YR 2/1) and very dark brown (10YR 2/2) silt loam, very dark brown (10YR 2/2) dry; moderate fine granular structure; slightly hard, very friable, slightly sticky and slightly plastic; many fine, medium and coarse roots; many fine interstitial pores; 10 percent rounded pebbles; extremely acid (pH 4.0); abrupt smooth boundary. (0 to 2 inches thick)
Bhs--2 to 4 inches; yellowish red (5YR 4/6) silt loam, strong brown (7.5YR 5/6) dry; dark reddish brown (5YR 3/2) coatings on faces of peds, dark reddish brown (5YR 3/3 and 3/4) dry; moderate medium subangular blocky structure; slightly hard, very friable, slightly sticky, slightly plastic, weakly smeary; common fine medium and coarse roots; few fine tubular pores; 10 percent pebbles, 5 percent iron concretions; strongly acid (pH 5.0); abrupt wavy boundary. (2 to 4 inches thick)
Bs1--4 to 10 inches; strong brown (7.5YR 5/6) silt loam, yellowish brown (10YR 5/8) dry; reddish brown (5YR 4/4) coatings on faces of peds, yellowish brown (10YR 5/4) dry; weak medium subangular blocky structure; slightly hard, very friable, slightly sticky, slightly plastic, weakly smeary; common medium and coarse roots; few fine tubular pores; 10 percent pebbles, few cobbles; strongly acid (pH 5.2); gradual wavy boundary. (6 or 8 inches thick)
Bs2--10 to 20 inches; strong brown (7.5YR 5/8) silt loam, light yellowish brown (10YR 6/4) dry; dark brown (7.5YR 4/4) coatings in cracks, dark yellowish brown (10YR 4/4) dry; massive; slightly hard, friable, slightly sticky, slightly plastic, weakly smeary; few medium roots; few fine tubular pores; 10 percent pebbles, few waterworn cobbles; strongly acid (pH 5.2); clear wavy boundary. (6 to 10 inches thick)
BC1--20 to 29 inches; light olive brown (2.5Y 5/4) silt loam, very pale brown (10YR 7/3 and 7/4) dry; many fine and medium distinct dark reddish brown (5YR 3/3), strong brown (7.5YR 5/8), and dark brown (7.5YR 4/4) coatings in old root channels, strong brown (7.5YR 5/6) and dark brown (7.5YR 4/4) dry; massive; slightly hard, friable, slightly sticky, slightly plastic, weakly smeary; few medium roots; common fine tubular pores; 10 percent pebbles, few cobbles; strongly acid (pH 5.2); clear smooth boundary. (4 to 9 inches thick)
BC2--29 to 36 inches dark brown (7.5 YR 3/2 and 3/4) silt loam, yellowish brown (10YR 5/6) dry; common fine faint strong brown (7.5YR 5/6) mottles, dark yellowish brown (10YR 4/4) dry; massive; slightly hard and hard, friable, slightly sticky and slightly plastic; few medium roots which are matted on top of 2Cr horizon; few fine tubular pores; 10 percent pebbles, few rounded cobbles; strongly acid (pH 5.2); abrupt smooth boundary. (0 to 7 inches thick)
2Bsm--36 to 75 inches; olive (5Y 5/3) and pale olive (5Y 6/3) ortstein compact glacial till that breaks to sandy loam, light gray (5Y 7/2) and light olive gray (5Y 6/2) dry; extremely hard, very firm, few fine tubular pores; 10 percent pebbles and few cobbles imbedded in till; few fine tubular pores; strongly acid (pH 5.2).
TYPE LOCATION: Snohomish County, Washington; approximately 7 miles northeast of Granite Falls; 1,250 feet west and 250 feet north of the southeast corner of sec. 15, T. 31 N., R. 7 E.
RANGE IN CHARACTERISTICS: The mean annual soil temperature at a depth of 20 inches ranges from 43 to 45 degrees F. Depth to a cemented dense glacial till ranges from 20 to 40 inches. Rock fragments in the particle-size control section ranges from 5 to 35 percent unweathered, and 0 to 20 percent weathered rock by weighted average.
The A horizon has value of 2 or 3 dry, and chroma of 1 or 2 dry or moist. It is extremely acid or very strongly acid. Some pedons have an E horizon with hue of 5YR, 7.5YR, or 10YR, value of 4 or 5 moist, 5 through 7 dry and chroma of 1 or 2 dry and moist. Some pedons have a 1/2- to 2- inch AB horizon.
The Bhs horizon has hue of 5YR or 7.5YR, value of 2 through 5 moist, 3 through 6 dry, and chroma of 1 through 6 moist and dry. It is silt loam, gravelly silt loam, gravelly loam or loam.
The Bs horizon has hue of 5YR, 7.5YR, or 10YR, value of 3 through 6 moist, 4 through 7 dry, and chroma of 2 through 8 moist and dry. It is loam, silt loam, sandy loam, gravelly silt loam, or gravelly loam. It is extremely acid to strongly acid.
The BC horizon has hue of 7.5YR, 10YR, or 2.5Y, value of 3 through 6 moist, 5 through 7 dry, and chroma of 2 through 8 moist or dry. The lower part of the BC horizon is usually very high in ash and has pockets of organic matters in old root channels. It is loam, silt loam, sandy loam, or gravelly loam. It is extremely acid to strongly acid.
The 2Bsm horizon is ortstein that breaks to sandy loam, gravelly loam or loam. It has hue of 10YR, 2.5Y or 5Y, value of 4 through 6 moist, 6 or 7 dry, and chroma of 2 through 4 moist and dry.
COMPETING SERIES: This is the Toklat series and the similar Barlow, Hartnit, Naptowne, Oso, Timberly, and Wollard series. All of these soils except Toklat soils lack an ortstein layer. In addition, Barlow, Naptowne, and Timberly soils are more than 40 inches deep. Oso soils have a lithic contact at 20 to 40 inches. Toklat soils have an E horizon 4 to 20 inches thick and are cemented in all parts of the spodic horizon. Wollard soils have 15 to 35 percent phyllite fragments in the particle-size control section and have a C1 horizon with a hue of 5Y or 2.5Y.
GEOGRAPHIC SETTING: Getchell soils formed in volcanic ash, colluvium and alpine glacial till. The till was derived from a wide variety of rock. The elevation ranges from 1,800 to 3,000 feet. Getchell soils are in a cool marine climate with cool, dry summers and cool, wet winters. The mean annual precipitation is 70 to 100 inches. The average annual temperature is about 43 degrees F. The frost-free season is 90 to 120 days.
GEOGRAPHICALLY ASSOCIATED SOILS: These are the Olomount and Oso soils and the competing Elwell, Hartnit, Potchub, and Verlot soils. Olomount and Oso soils are underlain by a lithic contact at a depth of 20 to 40 inches. Potchub and Verlot soils have more than 6 percent organic carbon in the upper 10 cm of the spodic horizon.
DRAINAGE AND PERMEABILITY: Moderately well drained; slow to rapid runoff; moderate permeability to the dense glacial till and very slow through it. A perched water table is as high as 1.5 to 3 feet at times from December through April.
USE AND VEGETATION: Used for woodland and wildlife habitat. Native vegetation is western hemlock, Douglas-fir, Pacific silver fir, and western redcedar, with an understory of western brackenfern, salal, Oregon-grape, trailing blackberry, red huckleberry, devilsclub, lady fern, bunchberry dogwood, blue-leaved huckleberry, salmonberry, longtube twinflower, and western swordfern.
DISTRIBUTION AND EXTENT: West slopes of the Cascade Mountains in northwestern Washington. The series is moderately extensive.
MLRA OFFICE RESPONSIBLE: Portland, Oregon
SERIES ESTABLISHED: Snohomish County, Washington, 1979.
REMARKS: Classification only changed 4/94 because of recent amendments to Soil Taxonomy. Fails criteria for spodic because of lack of an albic horizon. Characterization soil sample number S74WA61-2, 4-306-4-313, 84P3814-3816, and 78P0944-78P0945. Diagnostic horizons and features recognized in this pedon are a cambic horizon from 2 to 20 inches, and a cemented layer at 36 inches.