LOCATION NEAH                    WA

Established Series
Rev. RGC/HJP/TDT
02/2011

NEAH SERIES


The Neah series consists of moderately deep to bedrock, well drained soils that formed in residuum and colluvium from marine basalt and associated volcanic rocks on mountain slopes. Slopes are 15 to 85 percent. The average annual precipitation is about 110 inches and average annual temperature is about 42 degrees F.

TAXONOMIC CLASS: Medial, ferrihydritic, isofrigid Pachic Fulvudands

TYPICAL PEDON: Neah medial silt loam-forestland, on a 30 percent northwesterly aspect at an elevation of 1,700 feet in a Pacific silver fir-Alaska huckleberry-oxalis plant association. (When described on July 20, 1994, the soil was moist throughout. Colors are for moist soil unless otherwise stated.)

Oi--0 to 2 inches; slightly decomposed needles, leaves, twigs and cone fragments; abrupt smooth boundary. (1 to 3 inches thick)

Oe--2 to 3 inches; moderately decomposed organic materials; abrupt smooth boundary. (0 to 1 inch thick)

A--3 to 10 inches; very dark brown (10YR 2/2) medial silt loam, dark brown (10YR 3/3) dry; weak very fine and fine subangular blocky and weak very fine and fine granular structure; 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 tubular and irregular pores; 10 percent gravel; very strongly acid (pH 4.8); clear smooth boundary. (4 to 8 inches thick)

Bw1--10 to 25 inches; dark brown (10YR 3/3) gravelly medial silt loam, yellowish brown (10YR 5/4) dry; weak very fine, fine, and medium 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 tubular and irregular pores; 15 percent gravel, 10 percent cobbles; strongly acid (pH 5.1); clear wavy boundary.

Bw2--25 to 33 inches; dark brown (10YR 3/3) very cobbly medial silt loam, yellowish brown (10YR 5/4) dry; weak very fine, fine, and medium subangular blocky and weak very fine and fine granular structure; slightly hard, friable, slightly sticky and slightly plastic; weakly smeary; common very fine and fine and few medium and coarse roots; common very fine and fine tubular and irregular pores; 15 percent gravel, 20 percent cobbles; strongly acid (pH 5.4); abrupt wavy boundary. (Combined thickness of the Bw horizon is 16 to 32 inches.)

R--33 inches; volcanic rock.

TYPE LOCATION: Clallam County, Washington, about 3 miles north of Sappho, Washington, about 2465 feet west and 2375 feet north of the southwest corner of Section 8, T. 30 N., R. 12 W. (Latitude 48 degrees, 06 minutes, 50 seconds N., Longitude 124 degrees, 16 minutes, 12 seconds W.)

RANGE IN CHARACTERISTICS: The mean annual soil temperature is 41 to 47 degrees F. The difference between the mean summer and mean winter soil temperature is 5 to 9 degrees F. The mean summer soil temperature is 47 to 50 degrees F. and the mean winter soil temperature is 40 to 45 degrees F. These soils are usually moist, and have a surplus of available water on a monthly basis throughout the year (perudic). Depth to bedrock and thickness of the umbric epipedon is 20 to 40 inches. The particle-size control section from the mineral soil surface to the bedrock contact has andic soil properties with a weighted average of 5 to 35 percent rock fragments by volume. The andic soil material has an estimated moist bulk density of 0.30 to 0.70 g/cc, acid-oxalate extractable aluminum plus one half of the acid-oxalate extractable iron 2 to 6 percent, phosphate retention of 85 to 100 percent, and 15-bar water retention of 35 to 50 percent for air dried samples. Acid oxalate iron is 2.0 to 3.5 percent. It has 20 to 40 percent organic matter decreasing with depth. It has 2 to 8 cmol/kg of aluminum.

The A horizon has hue of 10YR or 7.5YR moist and dry, value of 2 or 3 moist and 3 through 5 dry, and chroma of 2 or 3 moist and 3 or 4 dry. Reaction is very strongly or strongly acid.

The Bw horizon has hue of 10YR or 7.5YR moist and dry, value of 4 or 5 dry, and chroma of 3 or 6 moist and 3, 4, or 6 dry. It is gravelly medial silt loam, very cobbly medial silt loam, or gravelly medial loam. Reaction is strongly or moderately acid.

COMPETING SERIES: These are the Hyas, Makah, and Mosscreek, Sooes, Stolzenberg series. Hyas, Makah and Mosscreek soils are greater than 60 inches to a lithic contact. Sooes and Stolzenberg soils have paralithic contacts and formed from sandstone, siltstone, and conglomerate materials.

GEOGRAPHIC SETTING: Neah soils are on mountain slopes of 15 to 85 percent. The soils formed in residuum and colluvium from marine basalt and associated volcanic rocks. Elevations are 400 to 2,400 feet. The mean annual precipitation is 90 to 120 inches. The mean annual temperature is 40 to 44 degrees F. The frost-free season is 120 to 140 days.

GEOGRAPHICALLY ASSOCIATED SOILS: These are the Adwell, Eatoncreek, Hyas, Kaweeta, Lizardlake, Urboden, Sooes, Stolzenberg and Zenobia soils. Adwell, Eatoncreek, Hyas, Kaweeta, Lizardlake, Urboden and Zenobia soils have a medial-skeletal particle-size control section.

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, western redcedar, Alaska huckleberry, Oregon oxalis, western swordfern, salmonberry, devilsclub, red huckleberry, deer fern, threeleaf foamflower, false lily-of-the-valley, and five leaf bramble.

DISTRIBUTION AND EXTENT: Washington; MLRA 4A. 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:

An umbric epipedon from 3 to 33 inches with depth, thickness, and organic-carbon requirements of a melanic epipedon (A, Bw1, and Bw2 subhorizons)
Andic soil properties - 3 to 33 inches (A, Bw1, and Bw2 subhorizons) based on lab data from the Murhut series.
Lithic contact - 33 inches
PSCS - 3 to 33 inches (A, Bw1, and Bw2 subhorizons)
This soil has a perudic moisture regime
All depths to diagnostic horizons and features are measured from the top of the first mineral horizon.


National Cooperative Soil Survey
U.S.A.