LOCATION KATULA WAEstablished Series
TAXONOMIC CLASS: Medial-skeletal, ferrihydritic, mesic Typic Fulvudands
TYPICAL PEDON: Katula very cobbly loam - on a west-facing 70 percent back slope, under coniferous forest at an elevation of 1,280 feet. (Colors are for moist soil unless otherwise stated. When described the soil was nearly dry to 10 inches and moist below.)
0i--7 to 2 inches; accumulation of Douglas-fir and western hemlock needles and twigs; clear smooth boundary. (2 to 6 inches thick)
0e--2 inches to 0; partially decomposed needles and twigs; abrupt smooth boundary. (1 to 3 inches thick)
A1--0 to 3 inches; dark reddish brown (5YR 3/2) very cobbly loam, reddish brown (5YR 4/4) dry; strong medium and fine granular structure; slightly hard, very friable, nonsticky and nonplastic and weakly smeary; many very fine and fine, common coarse and few medium roots; many fine tubular and irregular pores; 40 percent cobbles, 15 percent pebbles; moderately acid (pH 5.6); clear smooth boundary.
A2--3 to 13 inches; dark reddish brown (5YR 3/3) extremely cobbly loam, yellowish red (5YR 4/6) dry; strong medium and fine granular structure; slightly hard, very friable, nonsticky and slightly plastic and weakly smeary; many very fine and fine and common coarse and medium roots; many fine tubular and irregular pores; 45 percent cobbles, 20 percent pebbles; moderately acid (pH 5.6); gradual smooth boundary. (Combined thickness of the A horizon is 7 to 16 inches)
Bw1--13 to 18 inches; dark reddish brown (5YR 3/4) extremely cobbly clay loam, yellowish red (5YR 4/6) dry; moderate very fine and fine subangular blocky structure; slightly hard, friable, slightly sticky and slightly plastic and weakly smeary; common very fine and few fine roots; common fine tubular pores; 45 percent cobbles, 20 percent pebbles; moderately acid (pH 5.8); gradual smooth boundary.
Bw2--18 to 32 inches; dark brown (7.5YR 4/4) extremely cobbly clay loam, strong brown (7.5YR 5/6) dry; moderate very fine and fine subangular blocky structure; slightly hard, friable, slightly sticky and slightly plastic and weakly smeary; common fine and few very fine roots; common fine tubular and irregular pores; 70 percent cobbles, 10 percent pebbles; moderately acid (pH 5.8); abrupt smooth boundary. (Combined thickness of the Bw horizon is 13 to 24 inches)
R--32 inches; basalt, fractured in the upper part.
TYPE LOCATION: Pacific County, Washington; approximately 50 feet above steep road cut, 1/4 mile south on spur off D1500 logging road; 900 feet east, 2,500 feet south of northwest corner section 27, T. 12 N., R. 7 W.
RANGE IN CHARACTERISTICS: Depth to the lithic contact ranges from 20 to 40 inches. Organic carbon is less than 4 percent in some part of the upper 20 inches of the particle-size control section. Average annual soil temperature ranges from 48 to 50 degrees F. Angular cobbles, pebbles, and stones average from 60 to 80 percent by volume in the control section and are dominated by cobble-size fragments. The soil is moderately acid to very strongly acid throughout.
The A horizon has hue of 5YR, 7.5YR, or 10YR, value of 2 or 3 moist, 2 to 5 dry, and chroma of 2 or 3 moist, and 3 through 6 dry. Cobbles range from 15 to 45 percent and pebbles from 10 to 45 percent. Some pedons have up to 40 percent shot-like concretions in the upper part of the A horizon.
The Bw horizon has hue of 5YR, 7.5YR, or 10YR, value of 3 through 5 moist, 4 to 6 dry, and chroma of 2 through 6 moist, and 3 to 6 dry. It is extremely cobbly clay loam or extremely cobbly loam.
COMPETING SERIES: These are the Aschoff and Hoodview series and the Klone, Snahopish, Solleks, Squally and Traham series. Aschoff, Hoodview, Klone, and Squally soils lack a lithic contact at depth of 20 to 40 inches. Traham soils are very gravelly throughout and have 4 to 7 percent organic carbon throughout the upper 20 inches of the particle-size control section. Snahopish and Solleks soils have 4 to 7 percent organic carbon throughout the upper 20 inches of the control section.
GEOGRAPHIC SETTING: Katula soils are on back slopes and shoulder slopes and on narrow ridges in mountainous areas. Slopes are 5 to 90 percent. They are at elevations of 600 to 2,650 feet. These soils formed in colluvium and residuum from Eocene age basalt rock and an admixture of volcanic ash. They occur in a humid marine climate with cool, wet winters and cool, dry summers. Average annual precipitation ranges from 70 to 120 inches. The average January temperature is about 36 degrees F, average July temperature is about 62 degrees F, and the average annual temperature is about 48 degrees F. The growing season (28 degrees F) is 180 to 220 days.
GEOGRAPHICALLY ASSOCIATED SOILS: These are the Boistfort, Bunker, Lates, and Murnen soils. Boistfort and Bunker soils are more than 40 inches deep to a lithic contact and have less than 35 percent coarse fragments in control section. Lates and Murnen soils are frigid
DRAINAGE AND PERMEABILITY: Well drained; slow to medium runoff; moderate permeability.
USE AND VEGETATION: These soils are used for woodland. Native vegetation is western hemlock, Douglas-fir, western redcedar, bigleaf maple, with some Pacific silver fir and noble fir at higher elevations, and an understory of salal, red huckleberry, western swordfern, bedstraw, Oregongrape, vine maple, western brackenfern, starflower, rose, violet, American trailplant, Oregon fairybells, Pacific trillium, insideout flower, and Oregon oxalis.
DISTRIBUTION AND EXTENT: Southwestern Washington. This series is of moderate extent.
MLRA SOIL SURVEY REGIONAL OFFICE (MO) RESPONSIBLE: Portland, Oregon
SERIES ESTABLISHED: Pacific County, Washington, 1978.
Classification only updated 3/94. This description reflects a change in classification based on amendment 16. Diagnostic horizons and features recognized in this pedon are an umbric epipedon from the mineral surface to 13 inches, a cambic horizon from 13 to 32 inches, and a lithic contact at 32 inches. The upper 7 to 14 inches has an estimated moist bulk density of less than 1.00 g/cc, volcanic glass content of less than 5 percent, acid-oxalate extractable aluminum plus one-half iron of more than 2 percent. Bulk density is more than 0.90 g/cc below 14 inches.