LOCATION FAHNESTOCK WAEstablished Series
TAXONOMIC CLASS: Medial-skeletal, ferrihydritic Typic Haplocryands
TYPICAL PEDON: Fahnestock extremely gravelly medial sandy loam-forestland, on a 64 percent north-northeasterly aspect at an elevation of 3,080 feet in a Pacific silver fir-vanillaleaf-foamflower plant association. (When described on October 5, 1994, the soil was moist throughout. Colors are for moist soil unless otherwise stated.)
Oi--0 to 1 inch; slightly decomposed needles, leaves, and twigs; abrupt smooth boundary. (1 to 3 inches thick)
Oe--1 to 2 inches; moderately decomposed organic materials; abrupt smooth boundary. (0 to 1 inch thick)
A--2 to 8 inches; dark brown (10YR 3/3) extremely gravelly medial sandy loam, dark yellowish brown (10YR 4/4) dry; weak very fine and fine granular and weak very fine and fine subangular blocky structure; slightly hard, friable, nonsticky and nonplastic; weakly smeary; many very fine and fine and common medium and coarse roots; many very fine and fine irregular pores; 45 percent gravel, 20 percent cobbles; strongly acid (pH 5.1); clear smooth boundary. (5 to 10 inches thick)
Bw1--8 to 16 inches; dark yellowish brown (10YR 3/4) extremely gravelly medial sandy loam, yellowish brown (10YR 5/4) dry; weak very fine and fine subangular blocky and weak very fine and fine granular structure; slightly hard, friable, nonsticky and nonplastic; weakly smeary; many very fine and common fine, medium, and coarse roots; many very fine and common fine irregular pores; 45 percent gravel, 20 percent cobbles; moderately acid (pH 5.6); clear wavy boundary.
Bw2--16 to 27 inches; dark yellowish brown (10YR 3/6) extremely cobbly medial sandy loam, yellowish brown (10YR 5/6) dry; weak very fine and fine subangular blocky and weak very fine and fine granular structure; slightly hard, friable, nonsticky and nonplastic; weakly smeary; common very fine, fine, medium, and coarse roots; common very fine and fine irregular pores; 35 percent gravel, 35 percent cobbles; moderately acid (pH 5.8); clear wavy boundary.
Bw3--27 to 39 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; common very fine, fine, medium, and coarse roots; common very fine and fine irregular pores; 45 percent gravel, 25 percent cobbles; moderately acid (pH 5.8); clear wavy boundary. (Combined thickness of the Bw horizon is 25 to 35 inches.)
BC--39 to 56 inches; dark yellowish brown (10YR 3/6) extremely gravelly 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; few very fine, fine, and medium roots; few very fine and fine irregular pores; 45 percent gravel, 35 percent cobbles; moderately acid (pH 6.0); abrupt wavy boundary. (10 to 19 inches thick)
R--56 inches; fractured hard volcanic rock.
TYPE LOCATION: Clallam County, Washington, about 1 mile west-north west of Mt. Mueller, about 2640 feet west and 2375 feet south of the northeast corner of Section 16, T. 30 N., R. 10 W. (Latitude 48 degrees, 05 minutes, 42 seconds N., Longitude 123 degrees, 59 minutes, 55 seconds W.)
RANGE IN CHARACTERISTICS: Mean annual soil temperature is 41 to 43 degrees F. The mean summer soil temperature is 43 to 47 degrees F. The mean winter soil temperature is 37 to 41 degrees F. The difference between mean winter and mean summer soil temperatures is 6 to 9 degrees F. These soils are usually moist, and are dry 0 to 30 consecutive days in the soil moisture control section. Depth to bedrock is 40 to more than 60 inches. The particle-size control section has andic soil properties and 35 to 90 percent rock fragments by volume. The andic soil material has an estimated moist bulk density of 0.70 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. It has 1 to 2 cmol/kg of aluminum. Acid oxalate extractable iron is 1.5 to 3.0 percent. Below a depth of about 40 inches, andic soil properties are absent primarily due to the reduced organic matter and the higher bulk densities.
The A horizon has hue of 10YR or 7.5YR moist and dry, value of 3 or 4 moist and 4 or 5 dry, and chroma of 3 or 4 moist and 4 or 6 dry. It has 5 to 15 percent organic matter.
The Bw horizon has hue of 10YR or 7.5YR moist and dry, value of 3 through 5 moist and 5 through 8 dry, and chroma of 4 or 6 moist and dry. It is very gravelly medial sandy loam, very cobbly medial sandy loam, very gravelly medial loam, extremely gravelly medial sandy loam, extremely cobbly medial sandy loam, or extremely gravelly medial loam. Reaction is moderately acid. It has 1 to 7 percent organic matter.
The BC horizon has value of 3 or 4 moist and 6 or 7 dry and chroma of 4 or 6 moist and dry. Reaction is moderately acid. Moist bulk density if 0.90 to 1.20 g/cc. It has less than 1 to 2 percent organic matter.
COMPETING SERIES: These are the Balcher, Blackjack, Kahkwa, Mueller, Musgrove, Sniderpeak, Sorethumb, Stonybrook and Tylerpeak series. Balcher soils are deep to dense glacial till and are moderately well drained. Blackjack and Kahkwa soils are over sedimentary bedrock and have a difference between the mean winter and mean summer soil temperatures of 3 to 5 degrees F. Mueller soils are dry for 30 to 45 consecutive days. Musgrove soils are very strongly or strongly acid throughout the solum. Sniderpeak, Sorethumb, Stonybrook and Tylerpeak soils are 20 to 40 inches deep to bedrock.
GEOGRAPHIC SETTING: Fahnestock soils are on continental glaciated mountain slopes. Slopes are 15 to 90 percent. The soils formed in colluvium and residuum from marine basalt and associated volcanic rocks. Elevations are 2,500 to 3,500 feet. Average annual precipitation is 50 to 105 inches. Average annual temperature is 39 to 43 degrees F. The frost-free season is 120 to 150 days.
GEOGRAPHICALLY ASSOCIATED SOILS: These are the competing Balcher and Sniderpeak soils and the Buckman and Urgestein soils. Buckman soils are very shallow. Urgestein soils are moderately deep and have an umbric epipedon.
DRAINAGE AND PERMEABILITY: Well drained; moderate permeability.
USE AND VEGETATION: Timber production, wildlife habitat, recreation, and watershed. Native vegetation is Pacific silver fir, western hemlock, Alaska huckleberry, northern twinflower, deerfoot vanillaleaf, threeleaf foamflower, deer fern, queencup beadlily, and oneleaf foamflower.
DISTRIBUTION AND EXTENT: Northern slope of Olympic Mountains, Clallam County, Washington; MLRA 3. 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 39 inches
Andic soil properties - 2 to 39 inches
Lithic contact - 56 inches
PSCS - 2 to 42 inches
All depths to diagnostic horizons and other features are measured from the top of the first mineral horizon.