LOCATION HATCHET WAEstablished Series
TAXONOMIC CLASS: Medial-skeletal, amorphic Andic Haplocryods
TYPICAL PEDON: Hatchet very cobbly medial sandy loam - under a coniferous forest on a 46 percent northwest-facing lower back slope at an elevation of 3,600 feet. (The soil was moist when described. Colors are for moist soil unless otherwise stated. All textures are apparent field textures.)
Oi-0 to 2.5 inches; loose, partially decomposed organic litter composed of needles, twigs, cones, wood and bark chips; abrupt smooth boundary. (1 to 4 inches thick)
Oa--2.5 to 4 inches; decomposed organic material; abrupt smooth boundary. (1 to 4 inches thick)
E--4 to 5 inch; dark gray (10YR 4/1) medial sandy loam, gray (10YR 6/1) dry; massive; soft, very friable, nonsticky and nonplastic and weakly smeary; few roots; strongly acid (pH 5.4); abrupt wavy boundary. (0 to 3 inches thick where undisturbed)
Bs1--5 to 9 inches; dark brown (7.5YR 3/4) very cobbly medial sandy loam, brown (7.5YR 5/4) dry; moderate fine and medium subangular blocky structure; slightly hard, friable, slightly sticky and nonplastic and weakly smeary; common very fine, fine, medium and coarse roots; many fine pores; 20 percent angular and subangular pebbles and 20 percent cobbles; moderately acid (pH 5.6); clear wavy boundary.
Bs2--9 to 15 inches; brown (7.5YR 4/4) very cobbly medial sandy loam, light brown (7.5YR 6/4) dry; weak fine and medium subangular blocky structure; slightly hard, friable, slightly sticky and nonplastic and weakly smeary; common very fine, fine medium and coarse roots; common fine pores; 25 percent angular and subangular pebbles and 20 percent cobbles; moderately acid (pH 5.8); clear wavy boundary.
Bs3--15 to 25 inches; brown (7.5YR 4/4) extremely cobbly medial loam, pink (7.5YR 7/4) dry; weak fine and medium subangular blocky structure; slightly hard, friable, slightly sticky and nonplastic and weakly smeary; common very fine, fine, medium and coarse roots; common fine pores; 20 percent angular and subangular pebbles and 45 percent cobbles; moderately acid (pH 6.0); clear irregular boundary (Combined thickness of the Bs horizon is 15 to 26 inches)
C1--25 to 34 inches; dark yellowish brown (10YR 4/4) extremely cobbly medial sandy loam, very pale brown (10YR 7/4) dry; massive; slightly hard, friable, slightly sticky and nonplastic and weakly smeary; common very fine and fine, few medium and coarse roots; few fine pores; 40 percent angular and subangular pebbles and 40 percent cobbles; slightly acid (pH 6.2); abrupt irregular boundary.
C2--34 to 40 inches; yellowish brown (10YR 5/4) extremely cobbly medial sandy loam, very pale brown (10YR 7/3) dry; massive; slightly hard, friable, slightly sticky and nonplastic and weakly smeary; 40 percent angular pebbles and 45 percent cobbles; slightly acid (pH 6.2); abrupt irregular boundary. (Combined thickness of the C horizon is 14 to 20 inches)
2R--40 inches; fractured porphoritic andesite.
TYPE LOCATION: Cowlitz County, Washington, 2,230 feet north, and 1,000 feet west of the southeast corner of section 31, T. 10 N., R. 4 E., W.M. on Weyerhaeuser logging road No. 3340 near intersection with road No. 3345 below the summit of Elk Rock.
RANGE IN CHARACTERISTICS: Depth to the lithic contact is 20 to 40 inches. average annual soil temperature at a depth of 20 inches ranges from 40 to 42 degrees F. The particle-size control section averages 60 to 90 percent angular and subangular andesite pebbles and cobbles. Reaction below the E horizon is slightly acid or moderately acid throughout. Some pedons have a small admixture of pumice fragments in the upper part of the profile.
The E horizon has hue of 10YR or 2.5Y, value of 3 to 5 moist, 4 through 8 dry, and chroma of 0 through 3 moist and dry.
The Bs1 and Bs2 horizons have hue of 7.5YR or 5YR, value of 3 through 5 moist, 5 through 7 dry, and chroma of 4 through 6 moist and dry. They have 10 to 30 percent pebbles and 5 to 25 percent cobbles.
The Bs3 horizon has hue of 10YR through 5YR, value of 4 or 5 moist, 6 or 7 dry, and chroma of 4 through 6 moist and dry. It has 20 to 30 percent pebbles and 40 to 50 percent cobbles.
The C horizon has hue of 10YR or 7.5YR, value of 4 or 5 moist, 6 or 7 dry, and chroma of 3 or 4 moist and dry. It has 30 to 45 percent pebbles and 40 to 45 percent cobbles and the fine earth fraction is medial sandy loam, medial loam or medial clay loam.
COMPETING SERIES: These are the Crinker, Gilpar, Klawatti, Ohana, and Vabus series. Vabus soils have a paralithic contact at depths of 20 to 40 inches. Gilpar soils lack bedrock within depths of 40 inches. Crinkler soils have 40 to 70 percent channers throughout the particle-size control section and are strongly acid to extremely acid in the spodic horizon. Klawatti soils have 40 to 70 percent dunite or serpentine fragments throughout the particle-size control section. Ohana soils are 20 to 40 inches to a densic contact (2Cd horizon).
GEOGRAPHIC SETTING: Hatchet soils are on mountain slopes and ridgetops at elevations of 2,800 to 4,500 feet. Slopes are 5 to 90 percent. These soils formed in volcanic ash mixed with residuum and colluvium from volcanic ash and igneous rock including porphoritic andesite, olivine basalt or hard andesitic alloclastic breccia. Some Hatchet soils have a small admixture of pumice fragments. The climate is characterized by cool, dry summers and cold, wet winters. Average annual precipitation is 70 to 120 inches including considerable snowfall. Average annual temperature is 38 to 40 degrees F. Growing season (28 degrees F) is 70 to 140 days.
GEOGRAPHICALLY ASSOCIATED SOILS: These are the competing Ohana soils and the Cattcreek, Colter, Cotteral, Domell, Hoffstadt and Zynbar soils. Cattcreek soils are pumiceous or ashy-pumiceous over medial-skeletal. Colter and Cotteral soils are pumiceous or ashy-pumiceous over medial. Domell soils are medial and have a frigid temperature regime. Hoffstadt soils have a frigid temperature regime and are deep. Zynbar soils lack a spodic horizon, are medial and have a frigid temperature regime.
DRAINAGE AND PERMEABILITY: Well drained; slow to medium runoff; moderate permeability.
USE AND VEGETATION: Used for timber production, wildlife habitat and watershed. Overstory vegetation is Douglas-fir, western hemlock, Pacific silver fir, noble fir and western white pine. Ground vegetation is tree seedlings, red huckleberry, deer fern, common beargrass, Oregongrape, starflower, princespine, violet, western rattlesnake plantain, and Oregon ferrybells.
DISTRIBUTION AND EXTENT: Mountain slopes of the Cascade Range in southeastern Lewis, northwestern Skamania and northeastern Cowlitz Counties, Washington. The series is of moderate extent.
MLRA SOIL SURVEY REGIONAL OFFICE (MO) RESPONSIBLE: Portland, Oregon
SERIES ESTABLISHED: Lewis County, Washington, 1979.
REMARKS: Diagnostic horizons and features recognized in this pedon are an albic horizon from the mineral surface to 5 inch, a spodic horizon from 5 to 25 inches, a lithic contact at 40 inches, and andic properties from the surface to 36 inches. The particle-size control section is 14 to 40 inches. This description reflects a change in classification based on the 1998 Keys to Taxonomy.