LOCATION EDENBOWER OREstablished Series
TAXONOMIC CLASS: Clayey, smectitic, mesic Lithic Ultic Haploxerolls
TYPICAL PEDON: Edenbower clay - on a 6 percent convex south-facing slope in an unimproved pasture. When described, the soil was dry throughout. (Colors are for moist soil unless otherwise stated.)
A1--0 to 2 inches; very dark brown (10YR 2/2) clay, very dark grayish brown (10YR 3/2) dry; moderate fine and very fine granular and fine subangular blocky structure; hard, firm, very sticky and very plastic; many fine and very fine roots; common fine discontinuous interstitial pores; slightly acid (pH 6.4); clear smooth boundary. (0 to 3 inches thick)
A2--2 to 8 inches; very dark brown (10YR 2/2) clay, very dark grayish brown (10YR 3/2) dry; moderate coarse prismatic structure parting to strong very fine and fine granular and fine subangular blocky; very hard, very firm, very sticky and very plastic; common very fine and fine roots; common fine discontinuous interstitial pores; 5 percent basalt gravel; common worm casts; common pressure faces; slightly acid (pH 6.4); abrupt smooth boundary. (4 to 7 inches thick)
R--8 inches; partially weathered and semiconsolidated fractured basalt with common prominent very dark brown (10YR 2/2) clay films on rock fragments; common fine roots penetrating fissures to a depth of 31 inches.
TYPE LOCATION: Douglas County, Oregon; 1/2 mile west of Umpqua Community College; 1,400 feet east and 700 feet north of the SW corner SW1/4SW1/4 section 19, T. 26 S., R. 5 W.
RANGE IN CHARACTERISTICS: These soils are usually moist, but are dry throughout for 60 to 90 consecutive days during the summer. The mean annual soil temperature is 52 to 57 degrees F. The depth to a lithic contact is 4 to 10 inches. The profile has cracks that are open for 60 to 90 days during the summer. Rock fragments range from 0 to 15 percent gravel and cobbles.
The A horizon has hue of 10YR or 7.5YR, and chroma of 1 through 3 moist and dry. It is silty clay or clay, averaging 45 to 60 percent clay.
COMPETING SERIES: There are no competing series.
GEOGRAPHIC SETTING: Edenbower soils are on smooth convex ridgetops and hill slopes. Elevations are 350 to 2,000 feet. Slopes are 3 to 60 percent. The soils formed in fine textured residuum or colluvium weathered predominantly from basic igneous materials. The climate is characterized by warm dry summers and cool moist winters. The mean annual precipitation is 30 to 60 inches. The mean annual temperature is 50 to 55 degrees F. The frost-free season is 160 to 235 days.
GEOGRAPHICALLY ASSOCIATED SOILS: These are the Climax, Curtin, Dixonville, and Nonpareil soils and the competing Philomath soils. Curtin soils are deeper than 40 inches to bedrock and are somewhat poorly drained. Dixonville soils have an argillic horizon and are 20 to 40 inches deep to a paralithic contact. Nonpareil soils are loamy and are 10 to 20 inches deep to a paralithic contact.
DRAINAGE AND PERMEABILITY: Well drained; slow permeability.
USE AND VEGETATION: These soils are used for improved and unimproved pasture. Native vegetation is grass, wild rose, poison oak and patches of Oregon white oak.
DISTRIBUTION AND EXTENT: Interior valleys of southwestern Oregon; MLRA 5. The series is of moderate extent.
MLRA SOIL SURVEY REGIONAL OFFICE (MO) RESPONSIBLE: Davis, California
SERIES ESTABLISHED: Douglas County, Oregon, 1994.
REMARKS: The classification was changed from shallow Entic Ultic Haploxerolls to Lithic Ultic Haploxerolls in 1994.
Diagnostic horizons and features recognized in this pedon are:
Mollic epipedon -the zone from 0 to 8 inches (A1 and A2 horizons)
Lithic contact - 8 inches
Ultic feature - base saturation of 50 to 75 percent in some horizon between the surface and lithic contact.
Vertic feature - assumed linear extensibilty of 6.0cm from 0 to 8 inches.