LOCATION CONDORBRIDGE            OR

Established Series
Rev. CCD/JAS/RWL
06/2011

CONDORBRIDGE SERIES


The Condorbridge series consists of very deep, well drained soils formed in alluvium and debris flow deposits from sedimentary and igneous rocks. Condorbridge soils are on alluvial fans. Slopes are 3 to 15 percent. The mean annual precipitation is about 95 inches and the mean annual temperature is about 50 degrees F.

TAXONOMIC CLASS: Fine-loamy, isotic, isomesic Andic Humudepts

TYPICAL PEDON: Condorbridge gravelly medial loam, pastureland. (Colors are for moist soil unless otherwise noted.)

Ap--0 to 5 inches; very dark grayish brown (10YR 3/2) gravelly medial loam, brown (10YR 5/3) dry; moderate very fine and fine subangular blocky structure; firm, nonsticky, nonplastic and weakly smeary; common very fine, fine and medium roots throughout; 20 percent gravel and 5 percent paragravel; strongly acid (pH 5.4); abrupt smooth boundary. (4 to 7 inches thick)

A--5 to 12 inches; dark brown (10YR 3/3) gravelly medial loam, brown (10YR 5/3) dry; weak medium subangular blocky parting to moderate coarse granular structure; firm, slightly sticky, slightly plastic and weakly smeary; common very fine and fine roots throughout; 20 percent gravel and 10 percent paragravel; strongly acid (pH 5.4); clear smooth boundary. (6 to 13 inches thick)

BA--12 to 26 inches; dark brown (10YR 3/3) gravelly loam, light yellowish brown (10YR 6/4) dry; weak medium subangular blocky structure; friable, slightly sticky, slightly plastic, and weakly smeary; few very fine and fine roots throughout; 25 percent gravel and 10 percent paragravel; moderately acid (pH 5.6); clear smooth boundary. (10 to 20 inches thick)

Bw1--26 to 35 inches; dark brown (10YR 3/3) paragravelly clay loam, light yellowish brown (10YR 6/4) dry; moderate medium subangular blocky structure; friable, slightly sticky and slightly plastic; very few very fine roots throughout; 15 percent gravel and 10 percent paragravel; moderately acid (pH 5.6); clear smooth boundary. (7 to 20 inches thick)

Bw2--35 to 53 inches; dark yellowish brown (10YR 3/4) paragravelly clay loam, yellowish brown (10YR 5/4) dry; moderate coarse subangular blocky structure; friable, slightly sticky and slightly plastic; very few very fine roots throughout; 10 percent gravel and 20 percent paragravel; strongly acid (pH 5.4); clear smooth boundary. (10 to 25 inches thick)

Bw3--53 to 60 inches; dark yellowish brown (10YR 3/4) paragravelly clay loam, brownish yellow (10YR 6/6) dry; moderate coarse subangular blocky structure; friable, slightly sticky and slightly plastic; 15 percent gravel and 10 percent paragravel; moderately acid (pH 5.6); clear smooth boundary.

TYPE LOCATION: Tillamook County, Oregon; about 900 feet east and 300 feet south of the northwest corner of section 12, T. 4 S., R. 10 W. Willamette Meridian: Hebo, Oregon USGS 7.5 minute topographic quadrangle. Latitude 45 degrees, 14 minutes, 10 seconds N. and Longitude 123 degrees, 51 minutes, 41 seconds W.; NAD27.

RANGE IN CHARACTERISTICS: The soils are usually moist but and are dry for less than 45 consecutive days between the depths of 4 and 12 inches following the summer solstice. The mean annual soil temperature is 50 to 52 degrees F. The mean winter soil temperature and mean summer soil temperature vary less than 6 degrees C under full canopy. Depth to bedrock it greater than 60 inches. The umbric epipedon is 10 to 20 inches thick. The upper 4 to 7 inches of the epipedon has an Alox + Feox of 2.0 to 3.0 percent and a moist bulk density of 0.80 to 0.90 g/cc. The lower 6 to 13 inches has an Alox + Feox of 1.0 to 3.0 percent and a moist bulk density of 0.90 to 1.0 g/cc. Rock fragments, when present, are dominantly rounded and subrounded in shape and derived from alluvial origin. Reaction is strongly acid or moderately acid.

The Ap horizon has hue of 10YR or 7.5YR, value of 2 or 3 moist, 4 or 5 dry and chroma of 2 or 3 moist or dry. Texture is medial loam with 20 to 25 percent clay. It has 15 to 30 percent gravel and 0 to 10 percent paragravel.

The A horizon has hue of 10YR or 7.5YR, value of 2 or 3 moist, 4 or 5 dry and chroma of 2 or 3 moist and dry. Texture is medial loam, medial silt loam, loam, or silt loam with 20 to 25 percent clay. It has 0 to 30 percent gravel and 0 to 30 percent paragravel.

The BA horizon has hue of 10YR or 7.5YR, value of 3 or 4 moist, 5 or 6 dry and chroma of 3 or 4 moist, 2 to 6 dry. Texture is loam or silt loam with 20 to 25 percent clay. It has 0 to 30 percent gravel and 0 to 30 percent paragravel.

The Bw horizon has hue of 10YR or 7.5YR, value of 3 or 4 moist, 5 or 6 dry and chroma of 3 or 4 moist, 4 to 6 dry. Texture is clay loam, loam, or silty clay loam with 20 to 35 percent clay. It has 0 to 35 percent gravel, 0 to 10 percent cobbles, 0 to 35 percent paragravel, and 0 to 10 percent paracobbles.

The C horizon, when present, has hue of 10YR or 7.5YR, value 3 or 4 moist, 5 or 6 dry and chroma 3 or 4 moist, 4 to 6 dry. Texture is clay loam, sandy loam, loam, or silty clay loam with 10 to 35 percent clay. It has 0 to 35 percent gravel, 0 to 10 percent cobbles, 0 to 50 percent paragravel, and 0 to 10 percent paracobbles.

COMPETING SERIES: These are the Bigtree (T), Grassyknob, Horseprairie, Reedsport, Skipanon and Svensen soils. Bigtree soils have a mean annual soil temperature typically greater than 52 degrees F. Grassyknob soils are 20 to 40 inches deep to bedrock. Horseprairie soils have an umbric epipedon 20 to 40 inches thick. Reedsport soils are 20 to 40 inches deep to a paralithic contact. Skipanon and Svensen soils are 40 to greater than 60 inches deep to a paralithic contact, have Oi horizons, and when present, have rock fragments of angular and subangular shape derived from colluvial origin.

GEOGRAPHIC SETTING: The Condorbridge soils are on alluvial fans at elevations of 20 to 200 feet. Slopes are 3 to 15 percent. The soils formed in alluvium and debris flow deposits from sedimentary and igneous rocks. The climate is characterized by cool, moist summers and cool, wet winters. The mean annual precipitation is 80 to 110 inches. The mean annual temperature is 49 to 52 degrees F. The frost-free season is 160 to 260 days.

GEOGRAPHICALLY ASSOCIATED SOILS: These are the Chitwood, Hebo, Knappa, and Siletz soils. These soils occur on adjacent terraces. Chitwood soils have a fine family particle-size class and are moderately well drained. Hebo soils have a fine family particle-size class and are poorly drained. Knappa soils have a fine-silty family particle-size class. Siletz soils have a medial over loamy family particle-size class.

DRAINAGE AND PERMEABILITY: Well drained; moderate permeability.

USE AND VEGETATION: Most of these soils have been cleared and are used for forage production. Other uses include homesites and wildlife habitat. Native vegetation includes Sitka spruce, western hemlock, Douglas-fir, red alder, salmonberry, swordfern, and red elderberry.

DISTRIBUTION AND EXTENT: Fans along the Coastal Valleys in western Oregon; MLRA 4A. The series is small extent.

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

SERIES ESTABLISHED: Tillamook County, Oregon, 2006.

REMARKS: Diagnostic horizons and features in this pedon are:

Umbric epipedon - from the mineral soil surface to a depth of 12 inches (Ap and A horizons)
Cambic horizon - from a depth of 12 to 60 inches (BA, Bw1, Bw2, and Bw3 horizons)
Particle-size control section - from 10 to 40 inches (part of the A, BA, Bw1, and part of the Bw2 horizons)
Andic subgroup feature - from a depth of 0 to 12 inches (Ap and A horizons) with the zone from 0 to 5 inches qualifying for andic soil properties (assumed).

A proposal was submitted to NSSC (2000) to revise the definition of medial to also include those soil properties qualifying for the Andic subgroup under criteria #1 for andic soil properties. If accepted, medial modifiers would be used for those horizons meeting the andic subgroup criteria although not always meeting andic soil properties.


National Cooperative Soil Survey
U.S.A.