LOCATION GUNDERSON WAEstablished Series
TAXONOMIC CLASS: Medial-skeletal, ferrihydritic, frigid Oxyaquic Hapludands
TYPICAL PEDON: Gunderson gravelly medial fine sandy loam-forestland, on a 13 percent westerly aspect at an elevation of 1490 feet in a western hemlock/swordfern-oxalis plant association. (When described on September 6, 1996, the soil was moist throughout. Colors are for moist soil unless otherwise stated. All textures are apparent field textures.)
Oi--0 to 1 inch; slightly decomposed needles, leaves, twigs, and cone fragments; abrupt smooth boundary. (1 to 5 inches thick)
Oe--1 to 4 inches; moderately decomposed organic materials; abrupt smooth boundary. (0 to 3 inches thick)
A--4 to 8 inches; very dark grayish brown (10YR 3/2) gravelly medial fine sandy loam, brown (10YR 5/3) dry; weak very fine granular and weak very fine and 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; 20 percent gravel, 5 percent cobbles; very strongly acid (pH 4.8); abrupt smooth boundary. (2 to 5 inches thick)
Bw1--8 to 15 inches; dark brown (7.5YR 4/4) extremely gravelly medial fine sandy loam, reddish yellow (7.5YR 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; 55 percent gravel, 10 percent cobbles; moderately acid (pH 5.6); clear wavy boundary.
Bw2--15 to 27 inches; dark brown (7.5YR 3/4) very gravelly medial fine sandy loam, light brown (7.5YR 6/4) 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, fine, medium, and coarse roots; common very fine and fine irregular pores; 30 percent gravel, 10 percent cobbles, 10 percent stones; moderately acid (pH 5.6); clear wavy boundary.
Bw3--27 to 40 inches; dark yellowish brown (10YR 3/6) very gravelly medial fine sandy loam, yellow (10YR 7/6) 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 common fine, medium, and coarse roots; common very fine and fine irregular pores; 50 percent gravel, 5 percent cobbles; moderately acid (pH 5.6); clear wavy boundary. (Combined thickness of the Bw horizon is 30 to 45 inches.)
BC--40 to 47 inches; light olive brown (2.5Y 5/6) very gravelly loamy sand, pale yellow (2.5Y 7/4) dry; massive; weak very fine subangular blocky and weak very fine and fine granular structure; slightly hard, friable, nonsticky and nonplastic; many very fine, fine, medium, and coarse roots; common very fine and fine irregular pores; 50 percent gravel, 5 percent cobbles; moderately acid (pH 5.8); abrupt wavy boundary. (0 to 7 inches thick)
Cd--47 to 64 inches; olive brown (2.5Y 4/4) very gravelly sandy loam, pale yellow (2.5Y 7/3) dry; massive; hard, brittle, slightly sticky and slightly plastic; 45 percent gravel, 5 percent cobbles; moderately acid (pH 5.8).
TYPE LOCATION: Clallam County, Washington, about 2 1/3 miles southeast of Eagle Lakes, about 2200 feet east and 2200 feet south of the northwest corner of Section 12, T. 29 N., R. 10 W. (Latitude 48 degrees, 01 minutes, 24 seconds N., Longitude 123 degrees, 56 minutes, 08 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. Depth to dense till (densic material) is 40 to 60 inches. The particle-size control section has andic soil properties with a cumulative thickness of 35 to 50 inches and a weighted average of 35 to 70 percent rounded rock fragments. 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. Acid oxalate extractable iron is 1.5 to 3.0 percent.
The A horizon has chroma of 2 or 6 moist and 3 or 4 dry. It has 5 to 15 percent organic matter. It has 2 to 4 cmol/kg of aluminum.
The Bw horizon has hue of 10YR, 7.5YR, or 2.5Y 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 fine sandy loam, extremely gravelly medial fine sandy loam, very gravelly medial sandy loam, or very gravelly medial loam. It has 1 to 7 percent organic matter. It has 1 to 2 cmol/kg of aluminum. It has 5 to 20 percent field estimated clay and 40 to 60 percent sand.
The BC horizon has value of 4 or 5 moist and chroma of 4 or 6 moist. It is very gravelly sandy loam or very gravelly loamy sand. It lacks andic soil properties and has a moist bulk density of 1.00 to 1.30 g/cc.
The Cd horizon has value of 7 or 8 dry and chroma of 3 or 4 moist. It is very gravelly sandy loam or very gravelly loamy sand. It lacks andic soil properties and has a moist bulk density of 1.50 to 2.00 g/cc.
COMPETING SERIES: These are the Duckabush, Fricaba, Lotloh, Maidenpeak, Ruggedridge and Halfoss series. All of these soils formed over basalt or sedimentary colluvial or residual material and lack the densic material. Fricaba, Ruggedridge, and Halfoss soils are moderately deep to bedrock. Duckabush and Maidenpeak soils are over 40 inches deep to basalt. Lotloh soils are over 40 inches deep to sedimentary bedrock.
GEOGRAPHIC SETTING: Gunderson soils are on ground moraines. Slopes are 5 to 60 percent. The soils formed in alpine glacial till. Elevations are 1,250 to 1,750 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 Lotloh and Ruggedridge soils.
DRAINAGE AND PERMEABILITY: Moderately well drained; moderate over slow permeability. The lower part of the subsoil is saturated for over 20 consecutive and 30 cumulative days from November through April (Oxyaquic).
USE AND VEGETATION: Timber production, wildlife habitat, recreation, and watershed. Native vegetation is western hemlock, Douglas-fir, vine maple, red alder, Alaska huckleberry, salal, red huckleberry, starflower, violet, starry false-Solomons-seal, bunchberry dogwood, northern twinflower, threeleaf foamflower, western swordfern, false lily-of-the-valley, deerfoot vanillaleaf, trillium, deer fern, and Oregon oxalis.
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 40 inches (Bw1, Bw2, and Bw3 horizons)
Andic soil properties - 4 to 40 inches (A, Bw1, Bw2, and Bw3 horizons)
Densic layer - 47 to 64 inches (Cd layer)
PSCS - zone from 4 to 44 inches (A, Bw1, Bw2, Bw3, and part of BC horizon) 4 to 40 inches is medial-skeletal and ferrihydritic and 40 to 44 inches is loamy-skeletal and isotic. This series also meets the saturation requirements for oxyaquic subgroup.
All depths to diagnostic horizons and other features are measured from the top of the first mineral horizon.