LOCATION COLEPOINT               OR

Established Series
Rev. MHF/RTS/RWL
06/2011

COLEPOINT SERIES


The Colepoint series consists of deep, well drained soils formed in colluvium and residuum from metasedimentary or metavolcanic rock types. Colepoint soils are on broad ridgetops, benches, and side slopes of mountains. Slopes are 0 to 60 percent. The mean annual precipitation is about 110 inches and the mean annual temperature is about 49 degrees F.

TAXONOMIC CLASS: Fine-loamy, isotic, mesic Typic Humudepts

TYPICAL PEDON: Colepoint loam - woodland, on a 45 percent northwest-facing slope at 1,420 feet elevation. (When described on August 29, 1986, the soil was moist to a depth of 12 inches and dry below this depth. Colors are for moist soil unless otherwise noted.)

Oi--0 to 2 inches; slightly decomposed needles, leaves, twigs, and woody materials.

A1--2 to 8 inches; very dark brown (10YR 2/2) loam, dark grayish brown (10YR 4/2) dry; strong fine granular structure; slightly hard, friable, slightly sticky and slightly plastic; many fine and very fine roots; many fine and very fine irregular pores; 10 percent gravel; very strongly acid (pH 4.8); abrupt smooth boundary.

A2--8 to 14 inches; very dark grayish brown (10YR 3/2) gravelly loam, grayish brown (10YR 5/2) dry; strong very fine subangular blocky structure; slightly hard, friable, slightly sticky and slightly plastic; many fine and very fine roots; many fine and very fine tubular pores; 15 percent gravel; very strongly acid (pH 5.0); clear smooth boundary.

A3--14 to 20 inches; dark brown (10YR 3/3) gravelly loam, brown (10YR 5/3) dry; strong very fine subangular blocky structure; slightly hard, friable, slightly sticky and slightly plastic; many fine and very fine roots; many fine and very fine tubular pores; 15 percent gravel; strongly acid (pH 5.2); clear smooth boundary. (Combined thickness of the A horizon ranges from 14 to 20 inches)

Bw1--20 to 28 inches; dark yellowish brown (10YR 3/4) gravelly loam, light brown (7.5YR 6/4) dry; moderate very fine subangular blocky structure; slightly hard, friable, slightly sticky and slightly plastic; common fine and very fine roots; many fine and very fine tubular pores; 20 percent gravel; strongly acid (pH 5.4); clear smooth boundary.

Bw2--28 to 39 inches; dark yellowish brown (10YR 3/4) gravelly clay loam, light brown (7.5YR 6/4) dry; moderate very fine subangular blocky structure; slightly hard, firm, moderately sticky and moderately plastic; common fine and very fine roots; many fine and very fine tubular pores; 20 percent gravel; strongly acid (pH 5.3); clear smooth boundary.

Bw3--39 to 49 inches; dark yellowish brown (10YR 3/4) gravelly clay loam, light brown (7.5YR 6/4) dry; weak very fine subangular blocky structure; hard, firm, moderately sticky and moderately plastic; few fine and very fine roots; many fine and very fine tubular pores; 30 percent gravel; strongly acid (pH 5.3); abrupt wavy boundary. (Combined thickness of the Bw horizon ranges from 26 to 40 inches)

R---49 inches; hard metasedimentary rock.

TYPE LOCATION: Curry County, Oregon; located about 175 feet north and 200 feet west of the southeast corner of section 13,T. 39 S., R. 13 W. (Latitude 42 degrees, 11 minutes, 34 seconds N.; Longitude 124 degrees, 11 minutes, 05 seconds W.)

RANGE IN CHARACTERISTICS: The mean annual soil temperature is 47 to 54 degrees F. The soils are usually moist but are dry in all parts of the moisture control section for less than 45 consecutive days between depths of 4 and 12 inches in the four months following the summer solstice. The particle-size control section averages 25 to 35 percent clay and 20 to 30 percent rock fragments. The umbric epipedon is 14 to 20 inches thick and may include the upper part of the Bw horizon. The soil reaction is very strongly or strongly acid. Depth to bedrock and solum thickness is 40 to 60 inches.

The A horizon has value of 2 or 3 moist, 4 or 5 dry and chroma of 2 or 3 moist and dry. The A1 horizon is loam with 15 to 20 percent clay and 0 to 10 percent gravel. The A2 and A3 horizons are gravelly loam with 15 to 25 percent clay. It has 15 to 25 percent gravel.

The Bw horizon has hue of 10YR, 7.5YR or 2.5Y, value of 3 or 4 moist, 5 to 7 dry and chroma of 3 or 4 moist and dry. It is gravelly loam or gravelly clay loam with 25 to 35 percent clay. It has 20 to 35 percent gravel.

COMPETING SERIES: These are the Barbourville, Crutchfield, Cutshin, Horeb, Meda, Molalla, Stevenson, Threeforks, and Tuckasegee series. Barbourville soils have a mean annual soil temperature greater than 54 degrees F. Crutchfield soils are 20 to 40 inches deep to a lithic contact. Cutshin soils are 40 to more than 60 inches deep to bedrock and have a MAST greater than 54 degrees F. Horeb soils are more than 60 inches deep to bedrock and have mottles with chroma of 2 through 6 at depths of 24 to 36 inches. Meda soils are more than 60 inches deep to bedrock. Molalla soils are 40 to 60 inches deep to a paralithic contact and have hue of 5YR or redder throughout the profile. Stevenson soils are more than 60 inches deep to bedrock and have less than 15 percent rock fragments in the control section. Tuckasegee and Threeforks soils are more than 60 inches deep to bedrock.

GEOGRAPHIC SETTING: The Colepoint soils are on stable to metastable broad ridgetops, benches, and side slopes of forested mountains. Slopes are 0 to 60 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, Crutchfield, Fritsland, Grouslous, Hazelcamp and Skookumhouse soils. Averlande, Bravo, Cassiday, Crutchfield, Fritsland, Hazelcamp, and Skookumhouse soils occur on broad ridgetops, benches, or side slopes of forested mountains. Averlande, Hazelcamp, and Skookumhouse soils have argillic horizons. Averlande soils are 10 to 20 inches deep to bedrock and loamy-skeletal. Hazelcamp and Skookumhouse soils are clayey and have a paralithic contact. Bravo, Cassiday, and Crutchfield soils are 20 to 40 inches deep to bedrock. Bravo soils have an ochric epipedon. Cassiday soils are loamy-skeletal and have an ochric epipedon. Fritsland soils have an ochric epipedon. Grouslous soils occur on steep side slopes of forested mountains, are 10 to 20 inches deep to bedrock, and are loamy-skeletal.

DRAINAGE AND PERMEABILITY: Well drained; moderately slow permeability.

USE AND VEGETATION: The soils are mainly used for timber production, homesite development, watershed, recreation and wildlife habitat. The native vegetation is Douglas-fir, western hemlock, tanoak, Pacific madrone, Pacific rhododendron, evergreen huckleberry, salal, western swordfern, western rattlesnake plantain, hairy manzanita, western brackenfern, cascade Oregongrape, evergreen violet and sweetscented bedstraw.

DISTRIBUTION AND EXTENT: Mountainous areas of southwestern Oregon; MLRA 1. The series is not 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:

Umbric epipedon - from 2 to 20 inches (A1, A2, A3 horizons).

Cambic horizon - from a depth of 20 to 49 inches (Bw1, Bw2, Bw3 horizons).

Particle-size control section - from 12 to 42 inches (lower A2, A3, Bw1, Bw2 and upper Bw3 horizon).


National Cooperative Soil Survey
U.S.A.