LOCATION REEDSPORT OR

Established Series
Rev. RGC/TDT/RWL
06/2011

REEDSPORT SERIES

The Reedsport series consists of moderately deep, well drained soils that formed in colluvium and residuum from sedimentary rock. Reedsport soils are on side slopes, benches, and rounded ridgetops of mountains. Slopes are 0 to 90 percent. The mean annual precipitation is about 65 inches and the mean annual temperature is about 50 degrees F.

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

TYPICAL PEDON: Reedsport gravelly medial loam, on an east-facing slope of 55 percent under a deciduous forest at 180 feet elevation. (Colors are for moist soil unless otherwise stated.)

A--0 to 5 inches; very dark grayish brown (10YR 3/2) gravelly medial loam, brown (10YR 5/3) dry; moderate fine and medium granular structure; soft, friable, slightly sticky and slightly plastic; common fine and medium and few coarse roots; many very fine and fine irregular pores; 15 percent gravel and 5 percent paragravel; moderately acid (pH 5.6); clear smooth boundary. (5 to 8 inches thick)

Bw1--5 to 12 inches; dark brown (10YR 3/3) paracobbly medial loam, brown (10YR 5/3) dry; moderate fine and medium subangular blocky structure; soft, friable, slightly sticky and slightly plastic; common fine and medium and few coarse roots; many fine and medium continuous tubular pores; 20 percent sandstone paracobbles and 10 percent sandstone gravel; strongly acid (pH 5.4); clear smooth boundary. (2 to 8 inches thick)

Bw2--12 to 25 inches; dark brown (10YR 3/3) paracobbly loam, brown (10YR 5/3) dry; weak fine and medium subangular blocky structure; soft, friable, slightly sticky and slightly plastic; common fine and medium roots; common very fine and fine continuous tubular pores; 20 percent sandstone paracobbles and 10 percent sandstone gravel; strongly acid (pH 5.2); clear smooth boundary. (6 to 15 inches thick)

Bw3--25 to 32 inches; dark brown (10YR 3/3) paracobbly clay loam, brown (10YR 5/3) dry; weak fine and medium subangular blocky structure; soft, friable, slightly sticky and slightly plastic; common fine and medium roots; common very fine and fine continuous tubular pores; 20 percent sandstone paracobbles and 10 percent sandstone gravel; strongly acid (pH 5.2); clear smooth boundary. (6 to 10 inches thick)

Cr--32 inches; soft weathered sandstone.

TYPE LOCATION: Douglas County, Oregon; 3 miles east of Reedsport, Oregon; 2,500 feet west and 1,000 feet south of the northeast corner, sec. 6, T. 22 S., R. 11 W., W.M.

RANGE IN CHARACTERISTICS: The soils are usually moist, but are dry between depths of 4 and 12 inches for less than 45 consecutive days after the summer solstice. The mean annual soil temperature is 47 to 54 degrees F. The difference between mean summer and mean winter soil temperatures is 5 to 9 degrees F. Depth to a paralithic contact is from 20 to 40 inches. The umbric epipedon is 20 to 35 inches thick.

The A horizon has value of 2 to 3 moist, 3 to 5 dry and chroma of 1 to 3 moist and dry. It has 5 to 30 percent gravel and 0 to 20 percent sandstone parafragments. Organic matter is 5 to 12 percent. Soil reaction is moderately to strongly acid. It is medial loam and has ammonium-oxalate extractable Al + 1/2Fe of 2.0 to 3.0 percent, a phosphate retention of more than 85 percent, and a moist bulk density of 0.75 to 0.90 g/cc.

The A2, or AB horizon, when present, has ammonium-oxalate extractable Al + 1/2Fe of 1.0 to 3.0 percent, a phosphate retention of more than 85 percent, and a moist bulk density of 0.80 to 1.00 g/cc.

The Bw1 horizon has ammonium-oxalate extractable Al+1/2Fe of 1.0 to 2.0 percent, phosphate retention of more than 85 percent, and moist bulk density of 0.80 to 1.00 g/cc.

The Bw2 and Bw3 horizon has hue of 10YR or 7.5YR, value of 3 or 4 moist, 5 or 6 dry, and chroma of 2 or 3 moist, 3 or 4 dry. It is loam and clay loam with 5 to 25 percent gravel, 0 to 5 percent cobbles and 15 to 65 percent sandstone parafragments. It averages 20 to 35 percent clay. It is very strongly to strongly acid. Organic matter is 2 to 7 percent.

COMPETING SERIES: These are the Condorbridge, Grassyknob, Horseprairie, Skipanon and Svensen series. Grassyknob soils are 20 to 40 inches deep to a lithic contact. Condorbridge and Horseprairie soils are more than 60 inches deep to bedrock. Skipanon soils are 40 to 60 inches deep to bedrock and have a particle-size control section with less than 15 percent particles less than 0.1 mm. Svensen soils are 40 to 60 inches deep to bedrock.

GEOGRAPHIC SETTING: Reedsport soils are on side slopes, benchees, and rounded ridgetops of mountains and hills. Elevations are 50 to 1,800 feet. The soils formed in colluvium and residuum dominantly from sedimentary rock with some areas of metasedimentary or metavolcanic in origin. Slopes are 0 to 90 percent. The climate is characterized by cool, wet winters and cool, moist summers with fog. The mean annual temperature is 46 to 53 degrees F. The mean annual precipitation is 60 to 100 inches. The frost-free period is 120 to 270 days.

GEOGRAPHICALLY ASSOCIATED SOILS: These are the the Fendall, Millicoma, Salander, Templeton and Tolovana series. Millicoma soils are loamy-skeletal. Fendall soils have 40 to 50 percent clay in the textured control section. Salander, Templeton, and Tolovana soils are over 40 inches deep to bedrock. All of these soils occur on ridgetops or side slopes of mountains.

DRAINAGE AND PERMEABILITY: Well drained; permeability is moderate.

USE AND VEGETATION: These soils are used for timber production and wildlife habitat. Vegetation is Sitka spruce, western hemlock, western redcedar, Douglas-fir, red alder, and bigleaf maple with understory of vine maple, evergreen huckleberry, salmonberry, Oregongrape, salal, and swordfern.

DISTRIBUTION AND EXTENT: Coast range of west-central and southwestern Oregon; MLRA 4A. The series is of small extent.

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

SERIES ESTABLISHED: Douglas County, Oregon, 1990.

REMARKS: Diagnostic horizons and features in this pedon include:
Umbric epipedon - the zone from the surface to 32 inches (A, Bw1, Bw2, and Bw3 horizons)
Andic feature - the zone from 0 to 12 inches (A and Bw1 horizons) with the zone from 0 to 5 inches having andic soil properties.
Particle-size control section - the zone from 10 to 32 inches
The soil has assumed base saturation of less than 50 percent throughout the solum and more than 12 kg organic carbon per square meter to a depth of 32 inches.

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.