LOCATION GROUSLOUS          OR
Established Series
Rev. MHF/RTS/RWL
07/1999

GROUSLOUS SERIES


The Grouslous series consists of shallow, well drained soils formed in colluvium and residuum from metasedimentary or metavolcanic rock types. Grouslous soils are on steep side slopes of mountains. Slopes are 60 to 90 percent. The mean annual precipitation is about 110 inches and the mean annual temperature is about 49 degrees F.

TAXONOMIC CLASS: Loamy-skeletal, isotic, mesic Lithic Dystrudepts

TYPICAL PEDON: Grouslous very gravelly loam - woodland, on a 75 percent south-facing slope at 1,080 feet elevation. (Colors are for moist soil unless otherwise noted. When described on August 13, 1986, the soil was dry throughout.)

Oi--0 to 1 inch; partially decomposed needles, leaves, twigs, and woody materials.

A--1 to 5 inches; very dark grayish brown (10YR 3/2) very gravelly loam, grayish brown (10YR 5/2) dry; strong fine granular structure; slightly hard, friable, nonsticky and nonplastic; many fine roots; many fine irregular pores; 40 percent gravel; very strongly acid (pH 4.8); abrupt smooth boundary. (3 to 6 inches thick)

Bw1--5 to 9 inches; brown (10YR 4/3) very gravelly clay loam, pale brown (10YR 6/3) dry; strong fine subangular blocky structure; hard, firm, sticky and plastic; many fine roots; many fine tubular pores; 45 percent gravel; very strongly acid (pH 4.8); clear smooth boundary.

Bw2--9 to 17 inches; brown (10YR 4/3) extremely gravelly clay loam, pale brown (10YR 6/3) dry; moderate fine subangular blocky structure; hard, firm, moderately sticky and moderately plastic; common fine roots; many fine tubular pores; 65 percent gravel; very strongly acid (pH 4.8); abrupt wavy boundary. (Combined thickness of the Bw horizon ranges from 7 to 14 inches)

R--17 inches; fractured metasedimentary rock.

TYPE LOCATION: Curry County, Oregon; located about 1,850 feet south and 800 feet west of the northeast corner of section 16, T. 40 S., R. 13 W. W.M.(Latitude 42 degrees, 06 minutes, 56 seconds N.; Longitude 124 degrees, 14 minutes, 38 seconds W.)

RANGE IN CHARACTERISTICS: The mean annual soil temperature is 47 to 54 degrees F. The soils are usually moist and are dry for less than 45 consecutive days in all parts between depths of 4 and 12 inches in the four months following the summer solstice. The particle-size control section averages 27 to 35 percent clay and 45 to 70 percent rock fragments. Depth to bedrock and solum thickness is 10 to 20 inches. Hue is 10YR or 7.5YR.

The A horizon has value of 2 or 3 moist, 4 or 5 dry and chroma of 2 or 3 moist and dry. It is very gravelly loam or very stony loam with 18 to 27 percent clay. It has 35 to 55 percent gravel and 0 to 20 percent stones.

The Bw horizon has value of 4 or 5 moist, 5 or 6 dry and chroma of 3 or 4 moist and dry. It is very gravelly clay loam or extremely gravelly clay loam with 27 to 35 percent clay. It has 45 to 70 percent gravel.

COMPETING SERIES: These are the Arnot, Bugley, Dimal, Klinesville, Nassau, Rohan, Sylvatus, Unicoi, Weikert, and Zango series. Arnot, Klinesville Nassau, Unicoi, and Weikert soils have less than 27 percent clay in the particle-size control section. Bugley, Rohan, and Sylvatus soils have channery textures in the particle-size control section and MAST of more than 54 degrees F. Dimal soils have channery or flaggy textures in the particle-size control section and are strongly to moderately acid throughout. Zango soils have 30 to 45 percent gravel and 0 to 25 percent cobbles in the Bw horizon and are derived from tuff, breccia, and andesite.

GEOGRAPHIC SETTING: Grouslous soils are on steep, active side slopes of mountains. Slopes are 60 to 90 percent. The soils formed in colluvium and residuum derived from metasedimentary or metavolcanic rock types of the Dothan Formation. Elevation is 200 to 3,000 feet. The climate is characterized by warm wet winters and hot moist summers. The mean annual precipitation is 90 to 130 inches. The mean annual temperature is 45 to 53 degrees F. The frost-free period is 120 to 210 days.

GEOGRAPHICALLY ASSOCIATED SOILS: These are the Averlande, Bravo, Cassiday, Fritsland, Hazelcamp, and Skookumhouse soils. Averlande, Hazelcamp and Skookumhouse soils occur on broad ridgetops or stable benches of mountains and have argillic horizons. In addition, Hazelcamp and Skookumhouse soils are clayey and have a paralithic contact. Bravo and Cassiday soils occur on side slopes of mountains and are 20 to 40 inches deep to a lithic contact. Fritsland soils occur on side slopes of mountains, are 40 to 60 inches deep to bedrock, and are fine-loamy.

DRAINAGE AND PERMEABILITY: Well drained; moderately slow permeability.

USE AND VEGETATION: These soils are used mainly for woodland, watershed, recreation, and wildlife habitat. The native vegetation is Douglas fir, tanoak, canyon live oak, Pacific rhododendron, low Oregongrape, baldhip rose, evergreen huckleberry, salal, western swordfern, common beargrass, hairy manzanita, cascade Oregongrape, evergreen violet, and western brackenfern.

DISTRIBUTION AND EXTENT: Mountainous areas of southwestern Oregon; MLRA 1. The series is moderately extensive.

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

SERIES ESTABLISHED: Curry County, Oregon, 1995.

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

Ochric epipedon.

Cambic horizon - from a depth of 5 to 17 inches (Bw1, Bw2 horizons)

Lithic subgroup - 17 inches to lithic contact

Particle-size control section - from 11 to 17 inches (part of Bw2)


National Cooperative Soil Survey
U.S.A.