LOCATION FOEHLIN OREstablished Series
TAXONOMIC CLASS: Fine-loamy, mixed, superactive, mesic Typic Argixerolls
TYPICAL PEDON: Foehlin gravelly loam, orchard. (Colors are for moist soil unless otherwise noted.)
Ap--0 to 7 inches; very dark grayish brown (10YR 3/2) gravelly loam, grayish brown (10YR 5/2) dry; weak fine subangular blocky structure; slightly hard, friable, slightly sticky and slightly plastic; common medium, fine and very fine roots; 20 percent gravel; slightly acid (pH 6.4); abrupt smooth boundary. (0 to 8 inches thick)
A--7 to 13 inches; very dark grayish brown (10YR 3/2) gravelly loam, brown (10YR 5/3) dry; moderate medium subangular blocky structure; slightly hard, friable, slightly sticky and slightly plastic; common medium, fine and very fine roots; many very fine pores; 20 percent gravel; slightly acid (pH 6.4); clear wavy boundary. (4 to 12 inches thick)
Bt1--13 to 25 inches; dark brown (10YR 3/3) gravelly clay loam, pale brown (10YR 6/3) dry; moderate medium subangular blocky structure; slightly hard, friable, sticky and plastic; few medium, fine, and very fine roots; many very fine and fine pores; few faint dark brown (7.5YR 3/4) clay films on faces of peds; 15 percent gravel; slightly acid (pH 6.4); gradual wavy boundary. (8 to 16 inches thick)
Bt2--25 to 48 inches; dark brown (10YR 3/3) gravelly clay loam, pale brown (10YR 6/3) dry; moderate medium subangular blocky structure; hard, firm, sticky and plastic; few medium, fine and very fine roots; many very fine and fine pores; common distinct dark brown (7.5YR 4/3 dry) clay films on faces of peds; common light gray coarse sand grains; 20 percent gravel; slightly acid (pH 6.2); gradual smooth boundary. (16 to 30 inches thick)
Bt3--48 to 60 inches; brown (10YR 4/3) clay loam, pale brown (10YR 6/3) dry; moderate medium subangular blocky structure; hard, firm, sticky and plastic; common very fine and fine pores; common distinct dark brown and reddish brown (7.5YR 4/3 and 5YR 4/3 dry) clay films on faces of peds; common light gray coarse sand grains; 10 percent gravel; slightly acid (pH 6.4); gradual smooth boundary. (0 to 20 inches thick)
Bt4--60 to 66 inches; brown (10YR 4/3) gravelly clay loam, pale brown (10YR 6/3) dry; massive; hard, firm, sticky and plastic; few very fine pores; few distinct reddish brown clay films in pores and on fractures; 25 percent gravel; slightly acid (pH 6.4).
TYPE LOCATION: Josephine County, Oregon; 1/2 mile northeast of the village of Hugo, about 2,025 feet west and 775 feet south of the northeast corner of sec. 27, T. 34 S., R. 6 W., Willamette Meridian.
RANGE IN CHARACTERISTICS: The soils are usually moist but are dry during the summer for 80 to 110 consecutive days in all parts between depths of 4 and 12 inches. The mean annual soil temperature is about 52 to 56 degrees F. Subrounded rock fragments range from 5 to 30 percent in the control section. Depth to bedrock is 60 inches or more. The solum is 40 to over 60 inches thick.
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. It has 15 to 30 percent gravel.
The Bt 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 and dry. It is clay loam or gravelly clay loam with 27 to 35 percent clay. It has 10 to 30 percent gravel and 0 to 5 percent cobbles.
The C horizon when present, has the same range in hue, value and chroma as the Bt horizon. Faint to distinct redox concentrations are below a depth of 40 inches in some pedons.
COMPETING SERIES: These are the Colma, Dragoon, Duzel, Facey, Farrot, Immiant, Ladd, Lobitos, Los Gatos, Mehlhorn, Morical, Taneum, Tieton, Tweedy and Yaxon series. Colma soils have a mean annual soil temperature of 55 to 58 degrees F, have a solum less than 40 inches thick and have mottles in the subsoil. Dragoon, Duzel, Morical and Tweedy soils have a paralithic contact at 20 to 40 inches. Facy soils have bedrock at 40 to 60 inches, are on uplands and have 0 to 35 percent (2 to 5 mm) gravel throughout the particle-size control section. Farrot, Immiant, Lobitos, Los Gatos and Mehlhorn soils are 20 to 40 inches to a lithic contact. Taneum soils have a mean annual soil temperature of 48 to 50 degrees F and are dry for 60 to 80 consecutive days. Ladd soils have a mean annual soil temperature of 47 to 52 degrees F. Teiton soils have a mean annual soil temperature of 50 to 52 degrees F. Yaxon soils have a mean annual soil temperature of 49 to 52 degrees F and are neutral to mildly alkaline throughout the solum.
GEOGRAPHIC SETTING: The Foehlin soils are on alluvial fans and low stream terraces at elevation of 200 to 2,500 feet. Slopes range from 0 to 12 percent. The soils formed in moderately fine textured alluvium weathered from metamorphic, granitic, and ultramafic rocks. The climate is characterized by having hot and dry summers and warm and wet winters. The mean annual precipitation is typically 25 to 60 inches. In the interior river valleys of Curry County, Oregon, the mean annual precipitation may range to 90 inches. The mean annual temperature is 50 to 56 degrees F. The frost-free period is 140 to 235 days.
GEOGRAPHICALLY ASSOCIATED SOILS: These are the Brockman, Clawson, Copsey, Kerby and Takilma soils. Brockman soils are moderately well drained and are fine textured and serpentinitic. Clawson soils are somewhat poorly drained and are coarse-loamy. Copsey soils are poorly drained and fine textured and serpentinitic. Kerby soils have an ochric epipedon and lack an argillic horizon. Takilma soils are loamy-skeletal.
DRAINAGE AND PERMEABILITY: Well drained; moderately slow permeability.
USE AND VEGETATION: Foehlin soils are used for both irrigated pasture and native pasture, hayland, orchards, and homesites. The vegetation is mainly California black oak, Oregon white oak, common snowberry, poison oak, Idaho fescue, Pacific madrone and serviceberry.
DISTRIBUTION AND EXTENT: Interior valleys of southwestern Oregon, MLRA 5. The series is inextensive.
MLRA SOIL SURVEY REGIONAL OFFICE (MO) RESPONSIBLE: Davis, California
SERIES ESTABLISHED: Josephine County, Oregon, 1979.
REMARKS: CEC activity class superactive added 1/2000, competing series not updated at that time.
Diagnostic horizons and features include:
Mollic epipedon - from the surface to 13 inches (Ap, and A horizons).
Argillic horizon - from 13 to 66 inches (Bt1, Bt2, Bt3, and Bt4 horizons).
Particle-size control section from 13 to 33 inches.