LOCATION LOTLOH WAEstablished Series
TAXONOMIC CLASS: Medial-skeletal, ferrihydritic, frigid Typic Hapludands
TYPICAL PEDON: Lotloh extremely gravelly medial sandy loam-forestland, on a 76 percent south-southwesterly aspect at an elevation of 2,310 feet in a western hemlock/salal-swordfern plant association. (When described on August 24, 1996, the soil was moist throughout the soil moisture control section. Colors are for moist soil unless otherwise stated. All textures are apparent field textures.)
Oi--0 to 2 inches; slightly decomposed needles, leaves, twigs, and cone fragments; abrupt smooth boundary. (0.5 to 2.5 inches thick)
Oe--2 to 3 inches; moderately decomposed organic materials; abrupt smooth boundary. (0 to 1 inch thick)
A--3 to 8 inches; dark yellowish brown (10YR 3/4) extremely gravelly medial sandy loam, yellowish brown (10YR 5/4) dry; weak very fine and fine granular structure; slightly hard, friable, nonsticky and nonplastic; weakly smeary; many very fine, fine, medium, and coarse roots; many very fine and fine irregular pores; 75 percent gravel, 10 percent cobbles; moderately acid (pH 5.6); clear smooth boundary. (2 to 6 inches thick)
Bw1--8 to 17 inches; strong brown (7.5YR 4/6) extremely gravelly medial sandy loam, reddish yellow (7.5YR 6/6) dry; weak very fine and fine granular and weak very fine subangular blocky structure; slightly hard, friable, slightly sticky and slightly plastic; weakly smeary; many very fine, fine, medium, and coarse roots; many very fine and fine irregular pores; 70 percent gravel, 5 percent cobbles; moderately acid (pH 5.8); clear wavy boundary.
Bw2--17 to 27 inches; dark yellowish brown (10YR 3/6) extremely gravelly medial sandy loam, brownish yellow (10YR 6/6) dry; weak very fine and fine subangular blocky and weak very fine and fine granular structure; slightly hard, friable, slightly sticky and slightly plastic; weakly smeary; many very fine and fine and common medium and coarse roots; many very fine and fine irregular pores; 70 percent gravel 5 percent cobbles; moderately acid (pH 6.0); clear wavy boundary.
Bw3--27 to 42 inches; dark yellowish brown (10YR 4/6) extremely gravelly medial sandy loam, brownish yellow (10YR 6/6) dry; weak very fine and fine granular and weak very fine subangular blocky structure; slightly hard, friable, slightly sticky and slightly plastic; weakly smeary; many very fine, fine, medium, and coarse roots; many very fine and fine irregular pores; 60 percent gravel, 15 percent cobbles; moderately acid (pH 6.0); clear wavy boundary. (Combined thickness of the Bw horizon is 28 to 34 inches thick.)
BC--42 to 63 inches; dark yellowish brown (10YR 4/6) extremely gravelly sandy loam, yellow (10YR 7/6) dry, weak very fine and fine granular and weak very fine subangular blocky structure; slightly hard, friable, slightly sticky and slightly plastic; common very fine and fine and few medium and coarse roots; common very fine and fine irregular pores; 70 percent gravel, 5 percent cobbles; moderately acid (pH 6.0).
TYPE LOCATION: Clallam County, Washington, about 3.5 miles southeast of the Kloshe Nanich, about 100 feet west and 1320 feet south of the northeast corner of Section 6, T. 29 N., R. 10 W. (Latitude 48 degrees, 02 minutes, 30 seconds N., Longitude 124 degrees, 01 minutes, 45 seconds W.)
RANGE IN CHARACTERISTICS: Mean annual soil temperature is 43 to 47 degrees F. These soils are usually moist, and are dry 0 to 30 consecutive days in the soil moisture control section; udic moisture regime. Depth to bedrock is more than 40 inches. The particle-size control section has andic soil properties with a cumulative thickness of 30 to 40 inches and 35 to 90 percent rock fragments by volume. The andic soil material has an estimated moist bulk density of 0.60 to 0.90 g/cc, acid-oxalate extractable aluminum plus one half of the acid-oxalate extractable iron of 2 to 3 percent, phosphate retention of 85 to 100 percent, and 15-bar water retention of 15 to 30 percent for air dried samples. The particle-size control section has 5 to 20 percent field estimated clay and 40 to 60 percent sand. It has 1 to 2 cmol/kg of aluminum. Acid oxalate extractable iron is 1.5 to 3.0 percent.
The A horizon has value of 3 or 4 moist and 5 through 7 dry and chroma of 3, 4, or 6 moist and dry. It has 5 to 15 percent organic matter.
The Bw horizon has hue of 10YR, 7.5YR, or 2.5Y moist and dry, value of 3 through 6 moist and 6 through 8 dry, and chroma of 4 or 6 moist and dry. It is extremely gravelly medial fine sandy loam, extremely gravelly medial sandy loam, very gravelly medial very fine sandy loam, or extremely gravelly medial loam. It has 1 to 7 percent organic matter.
The BC horizon has moist bulk density of 0.90 to 1.20 g/cc. It has less than 1 to 2 percent organic matter.
COMPETING SERIES: These are the Duckabush, Fricaba, Gunderson, Maidenpeak, Ruggedridge and Halfoss series. Fricaba, Ruggedridge and Halfoss soils are moderately deep to bedrock. Duckabush soils are derived from basalt and have less sand in the particle-size control section. Gunderson soils are deep to dense till. Maidenpeak soils are dry for 30 to 45 consecutive days.
GEOGRAPHIC SETTING: Lotloh soils are on mountain slopes. Slopes are 20 to 80 percent. The soils formed in colluvium and residuum from sedimentary and metasedimentary rocks. Elevations are 1700 to 2800 feet. Average annual precipitation is 90 to 100 inches. Average annual temperature is 41 to 45 degrees F. The frost-free season is 140 to 160 days.
GEOGRAPHICALLY ASSOCIATED SOILS: These are the competing Gunderson, and Ruggedridge soils
DRAINAGE AND PERMEABILITY: Well drained; moderate permeability.
USE AND VEGETATION: Timber production, wildlife habitat, recreation, and watershed. Native vegetation is western hemlock, Douglas-fir, Alaska huckleberry, salal, red huckleberry, queencup beadlily, deerfoot vanillaleaf, western swordfern, Oregon-grape, baldhip rose, Oregon oxalis, and deer fern.
DISTRIBUTION AND EXTENT: Clallam County, Washington; MLRA 1. Series is of small extent.
MLRA SOIL SURVEY REGIONAL OFFICE (MO) RESPONSIBLE: Portland, Oregon
SERIES ESTABLISHED: Clallam County, Washington, 2000; Olympic National Forest.
REMARKS: Diagnostic horizons and features recognized in this pedon are the following:
Ochric epipedon
Cambic horizon - 8 to 42 inches
Andic soil properties - 3 to 42 inches
PSCS - 3 to 43 inches; (from 3 to 42 inches it is medial-skeletal and ferrihydritic and below 42 inches it is loamy-skeletal and isotic). The thickest part is medial-skeletal.
All depths to diagnostic horizons and other features are measured from the top of the first mineral horizon.