LOCATION ROSEBURG OREstablished Series
TAXONOMIC CLASS: Fine-loamy, mixed, superactive, mesic Pachic Ultic Argixerolls
TYPICAL PEDON: Roseburg loam - on a 1 percent slope in a cultivated field. When described, the soils were moist. (Colors are for moist soil unless otherwise noted.)
A1--0 to 4 inches; very dark grayish brown (10YR 3/2) loam, grayish brown (10YR 5/2) dry; weak fine granular and weak fine subangular blocky structure; hard, friable, slightly sticky and slightly plastic; many fine roots; many fine irregular and tubular pores; moderately acid (pH 5.7); abrupt smooth boundary. (4 to 8 inches thick)
A2--4 to 10 inches; very dark grayish brown (10YR 3/2) loam, grayish brown (10YR 5/2) dry; weak coarse subangular blocky structure; hard, firm, slightly sticky and slightly plastic; common very fine roots; common very fine tubular pores; moderately acid (pH 5.9); abrupt smooth boundary. (0 to 7 inches thick)
BAt--10 to 15 inches; very dark grayish brown (10YR 3/2) clay loam, grayish brown (10YR 5/2) dry; weak fine and medium subangular blocky structure; hard, firm, sticky and plastic; common very fine roots; many very fine and common fine and medium tubular pores; few faint (10YR 2/2) films on vertical faces of peds and lining pores; moderately acid (pH 6.0); clear smooth boundary. (0 to 7 inches thick)
Bt1--15 to 32 inches; dark brown (7.5YR 3/2) clay loam, brown (7.5YR 5/2) dry; weak medium prismatic structure parting to moderate medium subangular blocky; hard, firm, sticky and plastic; few fine roots; many very fine and common fine and medium tubular pores; common distinct (10YR 3/2) clay films on faces of peds and lining pores; slightly acid (pH 6.1); clear smooth boundary. (12 to 23 inches thick)
Bt2--32 to 41 inches; dark brown (7.5YR 3/4) loam, brown (7.5YR 5/4) dry; weak fine prismatic structure parting to moderate medium and fine subangular blocky; hard, firm, sticky and plastic; few fine roots; many very fine and common fine and medium tubular pores; common distinct clay films on faces of peds and lining pores; slightly acid (pH 6.2); clear smooth boundary. (7 to 11 inches thick)
BCt--41 to 50 inches; dark brown (7.5YR 3/4) sandy loam, brown (7.5YR 5/4) dry; weak medium subangular blocky structure; hard, friable, sticky and slightly plastic; few fine roots; many very fine and few fine and medium tubular pores; common distinct clay films on faces of peds and lining pores; slightly acid (pH 6.3); gradual wavy boundary. (5 to 14 inches thick)
C--50 to 64 inches; dark brown (7.5YR 3/4) sandy loam, brown (7.5YR 5/4) dry; massive; soft, very friable, nonsticky and nonplastic; slightly acid (pH 6.4).
TYPE LOCATION: Douglas County, Oregon; about 1/4 mile northeast of the confluence of the North and South Umpqua Rivers; 1,050 feet south and 1,100 feet east of the northwest corner of section 32, T. 26 S., R. 6 W.
RANGE IN CHARACTERISTICS: The soils are usually moist but are dry throughout in the control section for 60 to 90 consecutive days during the four-month period following the summer solstice. The mean annual soil temperature ranges from 52 to 57 degrees F. Depth to gravel is more than 60 inches and the solum is 40 to 60 inches thick. Hue is 10YR or 7.5YR. Organic carbon decreases regularly with increasing depth and the mollic epipedon is 20 to 40 inches thick.
The A horizon has value of 2 or 3 moist, 4 or 5 dry and chroma of 2 or 3 moist and dry. It has 0 to 15 percent gravel.
The Bt horizon has hue of 7.5YR or 10YR, value of 2 or 3 moist to a depth of 20 inches or more and 3 or 4 below 20 inches. Value of 4 or 5 dry and chroma of 2 through 4 moist and dry. It is loam, clay loam or sandy clay loam, averaging 25 to 35 percent clay and more than 15 percent coarser than very fine sand. It has 0 to 15 percent gravel.
The lower part of the solum and C horizon are stratified in some pedons.
Faint redoximorphic features are below depth of 40 inches in some pedons.
COMPETING SERIES: These are the Aptos, Buckeye, Campfour, Elmore, Nisene and Paragon series. Aptos soils are 20 to 40 inches deep to a paralithic contact and a mean annual soil temperature of 56 to 58 degrees F. Buckeye soils are 20 to 40 inches deep to bedrock. Campfour soils have hue of 2/5YR and 5YR in the subsoil. Elmore soils have mean annual soil temperature of 47 to 52 degrees F. and are 40 to 60 inches deep to a lithic contact. Nisene soils have mean annual soil temperature of 56 to 58 degrees F. and are 40 to 60 inches deep to a paralithic contact. Paragon soils are 20 to 40 inches deep to a paralithic contact.
GEOGRAPHIC SETTING: The Roseburg soils are on flood plains with slope gradients of 0 to 3 percent. The soils formed in loamy and sandy mixed alluvium. Elevations are 100 to 1,000 feet. Winters are cool and wet and summers are warm and dry with an average temperature of 50 to 55 degrees F. Average January temperature is 41 to 42 degrees F., and average July temeperature is 61 to 64 degrees F. The average growing season is 160 to 235 days. The mean annual precipitation is 30 to 60 inches.
GEOGRAPHICALLY ASSOCIATED SOILS: These are the Chapman, Coburg, and Evans soils. Chapman soils lack argillic horizons. Coburg soils are in the fine family. Evans soils are in the coarse-loamy family.
DRAINAGE AND PERMEABILITY: Well drained; slow runoff; moderate permeability. Flooding is rare.
USE AND VEGETATION: These soils are used for orchards, row crops, and hay and pasture. Native vegetation is Oregon white oak, ash, willow, Douglas fir, myrtle, blackberry, poison oak, and other shrubs and grasses.
DISTRIBUTION AND EXTENT: Umpqua valley, Oregon. The series is not extensive.
MLRA SOIL SURVEY REGIONAL OFFICE (MO) RESPONSIBLE: Davis, California
SERIES ESTABLISHED: Douglas County, Oregon, 1994.
REMARKS: The activity class was added to the classification in March of 2003. Competing series were not checked at that time. - ET
ADDITIONAL DATA: Characterization data on two profiles (S59-Ore-10-6 and 10-7) reported in SCS Riverside Soil Laboratory Report for soils sampled in west-central Oregon, July and October, 1959.