LOCATION BIGDUTCH                OR

Established Series
Rev. SLR/TDT
06/2011

BIGDUTCH SERIES

The Bigdutch series consists of moderately deep, well drained soils formed in residuum and colluvium derived from sandstone. Bigdutch soils are on plateaus. Slopes are 3 to 60 percent. The mean annual precipitation is about 60 inches and the mean annual temperature is about 43 degrees F.

TAXONOMIC CLASS: Loamy-skeletal, isotic, frigid Humic Dystrudepts

TYPICAL PEDON: Bigdutch gravelly loam-forested, on a 5 percent slope at an elevation of 3740 feet. (Colors are moist unless otherwise stated.)

Oi--0 to 2 inches; slightly decomposed needles and twigs.

A--2 to 6 inches; dark brown (7.5YR 3/3) gravelly loam, dark brown (10YR 4/3) dry; moderate fine granular structure; slightly hard, very friable, nonsticky and nonplastic; many very fine and common fine, medium and coarse roots; many very fine irregular pores; 30 percent gravel and 4 percent cobbles; strongly acid (pH 5.2); clear smooth boundary. (4 to 8 inches thick)

Bw1--6 to 19 inches; dark brown (7.5YR 3/4) gravelly loam, brown (7.5YR 5/4) dry; moderate very fine and fine subangular blocky structure; slightly hard, friable, slightly sticky and slightly plastic; common very fine, fine, medium and coarse roots; common very fine tubular pores; 20 percent gravel and 5 percent cobbles; very strongly acid (pH 4.8); abrupt wavy boundary. (12 to 20 inches thick)

Bw2--19 to 23 inches; dark brown (7.5YR 3/4) very 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; few very fine, fine, medium and coarse roots; common very fine tubular pores; 30 percent gravel and 25 percent cobbles; very strongly acid (pH 4.8); abrupt wavy boundary. (4 to 12 inches thick)

R--23 inches; fractured sandstone.

TYPE LOCATION: Douglas County, Oregon, on Big Dutchman Butte, 1000 feet north and 2200 feet east of the southwest corner of section 8, T. 31 S., R. 8 W., W.M. (Latitude 42 degrees, 52 minutes, 57 seconds N, Longitude 123 degrees, 40 minutes, 5 seconds W)

RANGE IN CHARACTERISTICS: Solum thickness and depth to bedrock is 20 to 40 inches. The mean annual soil temperature is 42 to 47 degrees F. The soil is usually moist but is dry within all parts of the moisture control section for less than 45 consecutive days following the summer solstice. Hue is 10YR or 7.5YR.

The A horizon has value of 2 or 3 moist, 3 to 5 dry, and chroma of 2 to 4 moist and dry. It has 15 to 35 percent gravel and 0 to 5 percent cobbles.

The Bw horizon has value of 3 or 4 moist, 4 to 6 dry, and chroma of 3 to 6 moist and dry. It is very cobbly clay loam, extremely cobbly loam, extremely cobbly clay loam or very gravelly clay loam. It has 20 to 35 percent clay. It has 10 to 40 percent gravel and 5 to 55 percent cobbles. It is very strongly acid to moderately acid.

COMPETING SERIES: This is the Ellinor (T) series. The Ellinor soils have hue of 5YR or 2.5YR.

GEOGRAPHIC SETTING: Bigdutch soils are on plateaus. The soils formed in sandstone from the Lookingglass Formation. Slopes are 3 to 60 percent. Elevations are 2700 to 3900 feet. The climate is characterized by cool, wet winters and warm, moist summers. The mean annual temperature is 40 to 45 degrees F, and the mean annual precipitation is 55 to 70 inches. The frost free period is 50 to 100 days.

GEOGRAPHICALLY ASSOCIATED SOILS: These are the Bohannon, Digger, Fernhaven, Preacher and Umpcoos soils. All of these series are mesic and are at lower elevations. Bohannon, Fernhaven, and Preacher are fine loamy. Umpcoos soils are shallow to sandstone. Digger soils lack an epipedon with colors of lower value than 4 when moist and 6 when dry.

DRAINAGE AND PERMEABILITY: Well drained; moderate permeability.

USE AND VEGETATION: Bigdutch soils are used for timber production, watershed and wildlife habitat. Natural vegetation is Douglas-fir, grand fir, western hemlock, golden chinkapin, Pacific rhododendron, salal, cascade Oregongrape, red huckleberry, western princespine, Pacific trillium, common beargrass, and snowbramble.

DISTRIBUTION AND EXTENT: Coastal Mountain Range of Oregon, MLRA 1. The series is inextensive.

MLRA SOIL SURVEY REGIONAL OFFICE (MO) RESPONSIBLE: Portland, Oregon

SERIES ESTABLISHED: Douglas County, Oregon, 1994.

REMARKS: Diagnostic horizons and features recognized in this pedon are:

Ochric epipedon
Humic subgroup - color requirements are meet from 2 to 23 inches
Cambic horizon - from 6 to 23 inches. (Bw1 and Bw2 horizons)
Base saturation is assumed to be less than 60 percent throughout the profile.
Particle-size control section - from 12 to 23 inches. Rock fragment content averages 40 percent

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National Cooperative Soil Survey
U.S.A.