LOCATION WALVILLE WAEstablished Series
TAXONOMIC CLASS: Medial, ferrihydritic, mesic Typic Hapludands
TYPICAL PEDON: Walville loam - under a coniferous forest on a 50 percent west facing convex slope at an elevation of 960 feet. (The soil was moist when described. Colors are for moist soil unless otherwise stated. All texture are apparent field textures.)
0l and 02-- 2 inches to 0; partially decomposed needles, twigs and leaves.
All--0 to l2 inches; dark brown (7.5YR 3/2) silt loam, brown (7.5YR 5/4) dry; moderate fine and medium granular structure; slightly hard, friable, slightly sticky, slightly plastic and weakly smeary; many fine and common medium and coarse roots; many fine irregular pores; 40 percent 2 to 5 mm size weathered tuff breccia fragments; moderately acid (pH 5.6); clear wavy boundary. (l0 to l4 inches thick)
Al2--l2 to l7 inches; dark brown (7.5YR 3/4) silty clay loam, brown (7.5YR 5/4) dry; moderate very fine and fine subangular blocky structure; slightly hard, slightly plastic and weakly smeary; many fine and common medium and coarse roots; many fine irregular pores; 50 percent 2 to 5 mm size weathered breccia fragments; moderately acid (pH 5.9); clear wavy boundary. (3 to 7 inches thick)
B2--l7 to 45 inches; dark brown (7.5YR 4/4) silty clay loam, light brown (7.5YR 6/4) dry; moderate medium subangular blocky structure; hard, firm, sticky, plastic and weakly smeary; common fine, medium and coarse roots; common fine pores; 50 percent 5 to 60 mm size weathered tuff breccia fragments; moderately acid (pH 5.9); abrupt irregular boundary. (l5 to 30 inches thick)
C--45 to 60 inches; dark brown (7.5YR 4/4) silty clay loam, light brown (7.5YR 6/4) dry; massive; hard, firm, sticky and plastic; l0 percent gravel-size weathered tuff breccia fragments, 70 percent cobble-size weathered tuff breccia fragments; moderately acid (pH 5.8).
TYPE LOCATION: Lewis County, Washington; NW1/4 NW1/4 SW1/4 sec. l, T. l2 N., R. 5 W.
RANGE IN CHARACTERISTICS: Mean annual soil temperature is 48 to 52 F. Relatively soft weathered tuff breccia fragments average 35 to 60 percent in the particle-size control section.
The A horizon has hue of 7.5YR or l0YR, value of 2 or 3 moist, 4 or 5 dry and chroma of 2 or 3 moist or dry.
The Al2 horizon has hue of l0YR or 7.5YR, value of 3 or 4 moist, 5 or 6 dry and chroma of 3 or 4 moist or dry.
The B2 horizon has hue of 7.5YR or l0YR. It is loam, silty clay loam or clay loam. Relatively soft weathered breccia fragments range from 35 to 60 percent.
The C horizon is loam, silty clay loam or clay loam and has 60 to 90 percent relatively soft weathered pyroclastic breccia fragments.
COMPETING SERIES: These are the AStoria, Boistfort, Bunker, Elochoman, Ilwaco, Kinney, Knappton, Lebam, Lebar, Lytell, Narel, Palix, Silcox, Swem, Sylvia, Vesta, Wellman, Willapa, and Zenker series. All of these soils lack 35 to 60 percent soft weathered tuff breccia fragments in the particle-size control section. Also, AStoria and Boistfort soils have silty clay or clay lower B horizons. Bunker and Kinney soils have l5 to 35 percent hard unweathered rock fragments in the control section. Elochoman soils lack pebble or cobble size fragments in the control section. Lytell, Swem, and Zenker soils have more than 35 percent soft weathered siltstone and sandstone fragments in the control section. Silcox soils have fine sandy loam or sandy loam in the control section.
GEOGRAPHIC SETTING: Walville soils are on uplands at elevations of 400 to l,800 feet. Slopes range from 8 to 90 percent. They formed in colluvium and residuum from tuff breccia and water deposited bedded tuff. Mean annual temperature is 47 to degrees 5l F. and mean annual precipitation is 70 to 90 inches. The growing season (28 F.) is l50 to 200 days.
GEOGRAPHICALLY ASSOCIATED SOILS: These are the competing Boistfort and Bunker soils, and the Buckhorn, Katula, Melbourne, and Thrash soils. Buckhorn soils are fine-loamy. Katula soils are medial-skeletal and 20 to 40 inches deep to hard bedrock. Melbourne soils are fine and have an argillic horizon. Thrash soils lack an umbric epipedon.
DRAINAGE AND PERMEABILITY: Well drained; medium to rapid runoff; moderate permeability.
USE AND VEGETATION: Used for timber production, wildlife habitat and watershed. Vegetation is Douglas-fir, western hemlock, western redcedar, red alder with an understory of western swordfern, Oregon-grape, salal, western brackenfern, rose and bedstraw.
DISTRIBUTION AND EXTENT: Lewis County, Washington. The series is of small extent.
MLRA SOIL SURVEY REGIONAL OFFICE (MO) RESPONSIBLE: Portland, Oregon
SERIES ESTABLISHED: Lewis County, Washington, l979.
REMARKS: Classification only changed 4/94 because of recent amendments to Soil Taxonomy.