LOCATION TUSIP WAEstablished Series
TAXONOMIC CLASS: Ashy over loamy, amorphic over isotic Typic Vitricryands
TYPICAL PEDON: Tusip sandy loam - in a clearcut area on a 37 percent northwest facing slope at an elevation of 3,500 feet. (Colors are for moist soil unless otherwise noted. All textures are apparent field textures.)
O--1 inch to 0; loose forest litter, needles, moss, partially decayed leaves, bark, and roots. (1 to 2 inches thick)
A--0 to 2 inches; dark brown (10YR 4/3) sandy loam, (volcanic ash and cinders), brown (10YR 5/3) dry; single grain, loose, nonsticky and nonplastic, weakly smeary; many very fine and fine roots; 5 percent soft subangular sandstone pebbles and 10 percent hard cinders; moderately acid (pH 5.6); abrupt smooth boundary. (2 to 6 inches thick)
Bs1--2 to 6 inches; dark brown (7.5YR 4/4) sandy loam, (volcanic ash and cinders),light brown (7.5YR 6/4) dry; single grain, loose, nonsticky and nonplastic, weakly smeary; many very fine and fine and few medium roots; 5 percent soft subangular sandstone pebbles and 10 percent hard cinders; strongly acid (pH 5.4); abrupt smooth boundary. (3 to 5 inches thick)
Bs2--6 to 15 inches; strong brown (7.5YR4/6) loamy sand, (volcanic ash and cinders), reddish yellow (7.5YR 6/6) dry; single grain, loose, nonsticky and nonplastic, weakly smeary; many very fine and fine and few medium roots; 5 percent soft subangular and 5 percent hard subangular sandstone pebbles and 10 percent hard cinders; strongly acid (pH 5.4); abrupt smooth boundary. (8 to 12 inches thick)
2Bs3--15 to 28 inches; yellowish brown (10YR 5/6) gravelly sandy loam, very pale brown (10YR 7/4) dry; moderate medium subangular blocky structure; slightly hard, firm, slightly sticky and slightly plastic; moderately smeary, few very fine, fine, and medium roots; 15 percent hard and 15 percent soft subangular sandstone pebbles; strongly acid (pH 5.2); clear irregular boundary. (8 to 13 inches thick)
2Bs4--28 to 38 inches; yellowish brown (10YR 5/8) gravelly fine sandy loam, yellow (10YR 7/6) dry; moderate medium subangular blocky structure; slightly hard, firm, slightly sticky and slightly plastic; weakly smeary; few very fine roots; 30 percent hard sandstone pebbles; 20 percent soft subangular sandstone pebbles; moderately acid (pH 5.8); abrupt smooth boundary. (6 to 20 inches thick)
2Bs5--38 to 43 inches; yellowish brown (10YR 5/8) very gravelly fine sandy loam, yellow (10YR 7/6) dry; moderate medium subangular blocky structure; slightly hard, firm, slightly sticky and slightly plastic; weakly smeary; 40 percent hard sandstone pebbles; 20 percent soft subangular sandstone pebbles; strongly acid (pH 5.2); abrupt smooth boundary. (0 to 10 inches thick)
2Cr--43 inches; weathered sandstone that can be cut with a spade.
TYPE LOCATION: Snoqualmie Pass Area, Pierce County, Washington; along St. Regis Road No. 21, 2,500 feet east and 300 feet north of southwest corner, sec. 14, T. 16 N., R. 6 E.
RANGE IN CHARACTERISTICS: Depth to paralithic contact is 40 to 60 inches. Mean annual soil temperature ranges from 41 to 44 degrees F. The upper 4 to 10 inches of the particle-size control section is more than 60 percent vitric volcanic ash and cinders. Cinders range from 5 to 10 percent. Hard rock fragments in the lower part of the particle-size control section range from 15 to 35 percent. Reaction is moderately acid or strongly acid throughout.
The A horizon has a value of 3 or 4 moist, 4 or 5 dry, and chroma of 2 or 3 moist or dry. It is a single grain or has weak subangular blocky structure.
The Bs horizon has hue of 7.5YR or 10YR, value of 4 or 5 moist, 5 or 6 dry, and chroma of 4 to 6 moist or dry. Texture is sandy loam or loamy sand with 5 to 10 percent hard cinders. It is single grain or has weak subangular blocky structure.
The 2Bs horizon has hue of 7.5YR, 10YR, or 2.5Y, value of 4 to 6 moist, 5 to 8 dry, and chroma of 4 to 8 moist, and 4 to 6 dry. Texture is gravelly sandy loam or gravelly fine sandy loam with 15 to 30 percent hard pebbles. The lower part has up to 45 percent hard pebbles in some pedons.
COMPETING SERIES: These are the Scar and Spukwush series. Scar soils have a xeric moisture regime and a solum less than 35 inches thick. Spukwush soils are 18 to 27 percent clay in the lower part of the particle-size control section.
GEOGRAPHIC SETTING: Tusip soils are on mountain slopes and rounded ridge crests at elevations of 2,700 to 3,600 feet. Slopes range from 15 to 65 percent. Tusip soils formed in a mantle of volcanic ash, pumice, and cinders over residuum and colluvium from sandstone and volcanic ash. The average annual precipitation is 80 to 100 inches with a large part of it in the form of snow. The mean annual temperature is 39 to 44 degrees F. Frost-free season is 120 to 140 days.
GEOGRAPHICALLY ASSOCIATED SOILS: These are Cattcreek, Cotteral, Ethania, Jonas, Pheeney, Reichel, Stahl, and Vailton. Cattcreek and Ethania soils are cindery over medial-skeletal. Cotteral soils are cindery over medial. Jonas, Pheeney, and Vailton soils are frigid. Reichel soils are medial and have an umbric epipedon. Stahl soils are medial-skeletal and have an umbric epipedon.
DRAINAGE AND PERMEABILITY: Well drained; medium runoff; moderate permeability.
USE AND VEGETATION: Used for timber production, wildlife habitat, and watershed. Vegetation is western hemlock, Pacific silver fir, and Douglas-fir, with an understory of salal, tall blue huckleberry, deer fern, western swordfern, longtube twinflower, and common beargrass.
DISTRIBUTION AND EXTENT: Western slopes of the Cascade Mountains in west central Washington. Series is of small extent.
MLRA SOIL SURVEY REGIONAL OFFICE (MO) RESPONSIBLE: Portland, Oregon
SERIES PROPOSED: Snoqualmie Pass Area, Pierce County, Washington, 1982.
REMARKS: Diagnostic horizons and features recognized in this pedon are: ochric epipedon from the mineral surface to 2 inches; a spodic horizon from 2 to 43 inches, and a lithologic change at 15 inches from ashy to loamy soil material. The spodic horizon is assumed not to meet chemical requirements for a spodic horizon, but is assumed to have silt-sized and larger pellets and cracked coatings on sand grains.