LOCATION SPEAKER            OR+CA
Established Series
Rev. DKS/AON/TDT
8/98

SPEAKER SERIES


The Speaker series consists of moderately deep, well drained soils that formed in colluvium weathered from sedimentary and metamorphic rocks. Speaker soils are on low rolling foot slopes and side slopes and have gradients of 2 to 75 percent. The mean annual precipitation is about 45 inches and the mean annual temperature is about 50 degrees F.

TAXONOMIC CLASS: Fine-loamy, mixed, active, mesic Ultic Haploxeralfs

TYPICAL PEDON: Speaker gravelly loam, forested on a 45 percent slope. (Colors are for moist soil unless otherwise noted.)

O--3/4 inch to 0; duff layer.

A1--0 to 3 inches; dark brown (7.5YR 3/3) gravelly loam, brown (7.5YR 5/3) dry; moderate fine granular structure; slightly hard, friable, slightly sticky and slightly plastic; many fine and medium roots; many irregular pores; 30 percent gravel and cobbles; slightly acid (pH 6.1); abrupt smooth boundary. (2 to 4 inches thick)

A2--3 to 6 inches; dark brown (7.5YR 3/4) gravelly loam, brown (7.5YR 5/4) dry; moderate fine subangular blocky structure; slightly hard, friable, slightly sticky and slightly plastic; many fine and medium roots; many very fine and fine tubular pores; 20 percent gravel and cobbles; moderately acid (pH 5.8); clear smooth boundary. (2 to 5 inches thick)

BA--6 to 13 inches; reddish brown (5YR 4/4) gravelly loam, reddish brown (5YR 5/4) dry; moderate fine subangular blocky structure; slightly hard, friable, sticky and plastic; many fine and common medium roots; many very fine and fine tubular pores; 20 percent gravel; moderately acid (pH 5.8); clear smooth boundary. (4 to 11 inches thick)

2Bt--13 to 30 inches; yellowish red (5YR 4/6) gravelly clay loam, yellowish red (5YR 5/6) dry; moderate fine subangular blocky structure; hard, firm, sticky and plastic; common medium and coarse roots; common very fine and fine tubular pores; few moderately thick clay films; 20 percent partially weathered gravel; moderately acid (pH 5.6); gradual wavy boundary. (12 to 20 inches thick)

2Crt--30 to 33 inches; weathered bedrock with common dark red (2.5YR 3/6) clay films and black stains in fractures.

TYPE LOCATION: Josephine County, Oregon; about 1 1/2 miles east from powerline road on Daisy Mountain Road; about 100 feet west and 1,620 feet south of the NE corner of sec. 21, T. 34 S., R. 5 W., Willamette Meridian.

RANGE IN CHARACTERISTICS: The mean annual soil temperature is 47 to 54 degrees F. The soils are usually moist but are dry between depths of 4 and 12 inches for 60 to 90 consecutive days following the summer solstice. Depth to a paralithic contact and thickness of the solum range from 20 to 40 inches. The particle-size control section averages 0 to 30 percent gravel, 0 to 5 percent cobbles, 25 to 35 percent clay, and more than 15 percent fine sand and coarser but less than 15 percent coarse and very coarse sand. Clean sand and silt coatings are common on faces of peds in the upper part of the B horizon in some pedons.

The A horizon has hue of 10YR or 7.5YR, value of 3 or 4 moist, 4 through 7 dry, and chroma of 2 through 6 moist and dry. Rock fragments averages 5 to 30 percent gravel and 0 to 5 percent cobbles. Reaction is strongly to slightly acid. The horizon has 2 to 4 percent organic matter.

The Bt horizon has hue of 7.5YR or 5YR, value of 4 or 5 moist, 4 through 7 dry, and chroma of 4 through 6 moist and dry. Textures are gravelly clay loam, clay loam, gravelly loam or loam. There are few to common moderately thick clay films. Stonelines are in some pedons. Reaction is very strongly to moderately acid.

COMPETING SERIES: These are the Bernhill, Boomer, Casabonne, Centralia, Cherryhill, Cle Elum, Cohasset, Crozier, Fives, Holland, Hood, Hotaw, Kalama, Latourell, Lettia, Musick, Norling, Sanhedrin, Underwood, Verelum, Wilkeson, Wohly and Wolfpeak series. Bernhill, Boomer, Casaboone, Centralia, Cherryhill, Cohasset, Fives, Holland, Hood, Kalama, Latourell, Lettia, Musick, Sanhedrin, Underwood, Varelum, Wilkeson and Wolfpeak soils are over 40 inches deep. Crozier and Wohly soils are 20 to 40 inches to a lithic contact. Norling soils are dry for 45 to 60 consecutive days. Cle Elum soils have an albic horizon. Hotaw soils are dry for 120 to 150 consecutive days.

GEOGRAPHIC SETTING: Speaker soils are on hillslopes and mountain slopes with gradients of 2 to 75 percent. These soils are at elevations of 400 to 4,800 feet. The soils formed in moderately fine textured colluvium weathered from sedimentary and volcanic sandstone, conglomerate sandstone and metavolcanic rocks. Summers are warm and dry and winters are cool and moist with an average annual precipitation of 30 to 60 inches. The mean annual temperature is 45 to 56 degrees F. The frost-free period is 100 to 235 days.

GEOGRAPHICALLY ASSOCIATED SOILS: These are the Beekman, Colestine, Josephine and Vermisa soils. Josephine soils are more than 40 inches deep to bedrock. Beekman, Colestine, and Vermisa soils lack an argillic horizon.

DRAINAGE AND PERMEABILITY: Well drained; medium to high runoff; moderately slow permeability.

USE AND VEGETATION: This soil is used for timber production, water supply, recreation, and wildlife habitat.Natural vegetation is mainly Douglas fir, Pacific madrone, ponderosa pine, California black oak, cascade Oregongrape, common snowberry and whipplevine.

DISTRIBUTION AND EXTENT: Southwestern and west-central Oregon and coastal mountains of northern California. The series is extensive.

MLRA SOIL SURVEY REGIONAL OFFICE (MO) RESPONSIBLE: Davis, California

SERIES ESTABLISHED: Josephine County, Oregon, 1979.


National Cooperative Soil Survey
U.S.A.