LOCATION TAKILMA OREstablished Series
TAXONOMIC CLASS: Loamy-skeletal, mixed, superactive, mesic Entic Ultic Haploxerolls
TYPICAL PEDON: Takilma cobbly loam, oak-grassland with a 1 percent slope. (Colors are for moist soil unless otherwise noted.)
A--0 to 6 inches; dark brown (7.5YR 3/2) cobbly loam, brown (7.5YR 5/3) dry; moderate fine subangular blocky and moderate very fine granular structure; slightly hard, friable, slightly sticky and slightly plastic; many very fine roots; many interstitial pores; 20 percent cobbles and 15 percent gravel; slightly acid (pH 6.2); clear smooth boundary. (4 to 6 inches thick)
Bw--6 to 18 inches; dark brown (7.5YR 3/3) very cobbly loam, brown (7.5YR 5/3) dry; weak medium subangular blocky structure; slightly hard, friable, slightly sticky and slightly plastic; common medium and fine roots; many interstitial pores; 25 percent cobbles and 25 percent gravel; slightly acid (pH 6.4); clear smooth boundary. (8 to 14 inches thick)
C--18 to 60 inches; dark brown (7.5YR 3/3) extremely cobbly sandy loam, brown (7.5YR 5/3) dry; massive; slightly hard, friable, slightly sticky and slightly plastic; few medium roots; many interstitial pores; 35 percent cobbles and 45 percent gravel; neutral (pH 6.6).
TYPE LOCATION: Josephine County, Oregon; about 0.25 mile north of the Takilma store and 200 feet west of the Takilma-Bridgeview Road, 1,030 feet north and 820 feet east of the southwest corner of sec. 26, T. 40 S., R. 8 W.
RANGE IN CHARACTERISTICS: The solum thickness is 12 to 20 inches. Depth to bedrock is 60 inches or more. The mean annual soil temperature is 52 to 57 degrees F. The soils are usually moist, but are dry between depths of 8 and 24 inches for 60 to 80 consecutive days following the summer solstice. The mollic epipedon is 12 to 20 inches thick. The 10 to 40 inch control section averages 12 to 18 percent clay, 30 to 35 percent gravel, and 25 to 45 percent cobbles.
The A horizon has hue of 7.5YR or 10YR, value of 2 or 3 moist, 4 or 5 dry, and chroma of 2 or 3 moist and 2 through 4 dry. It has 10 to 20 percent gravel and 15 to 35 percent cobbles and averages 25 to 35 percent total rock fragments.
The Bw horizon has hue of 7.5YR or 10YR, value of 3 or 4 moist, 4 or 5 dry, and chroma of 2 or 3 moist and 3 or 4 dry. It is loam or clay loam with 18 to 30 percent clay. It has 20 to 30 percent gravel and 15 to 30 percent cobbles.
The C horizon has hue of 7.5YR or 10YR, value of 3 or 4 moist, 5 or 6 dry, and chroma of 3 or 4 moist and dry. It is sandy loam or loam with 10 to 18 percent clay. It has 30 to 50 percent gravel and 10 to 35 percent cobbles. Below a depth of 40 inches, stratification is common.
COMPETING SERIES: This is the Knapke series. Knapke soils have 18 to 27 percent clay in the particle-size control section.
GEOGRAPHIC SETTING: Takilma soils are on nearly level low stream terraces at elevations of 200 to 2,500 feet. These soils formed in cobbly mixed alluvium. The climate is characterized by hot, dry summers and cool, moist winters. The annual precipitation is typically 18 to 60 inches but may range up to 90 inches in the high winter rainfall areas of Curry County, Oregon. The mean January temperature is 37 degrees F, the mean July temperature is 68 degrees F, and the mean annual temperature is 50 to 56 degrees F. The frost-free period is 140 to 210 days.
GEOGRAPHICALLY ASSOCIATED SOILS: These are the Kerby and Foehlin soils. Kerby soils are fine-loamy and have an ochric epipedon. Foehlin soils are fine-loamy and have an argillic horizon.
DRAINAGE AND PERMEABILITY: Well drained; slow runoff; moderately rapid permeability in the B horizon and rapid in the C horizon.
USE AND VEGETATION: Takilma soils are used for irrigated pasture, wildlife habitat and homesite development. Native vegetation is mainly Oregon white oak, Douglas fir, California black oak, California laurel, incense cedar, ponderosa pine, Pacific madrone, common snowberry, wedgeleaf ceanothus, and grasses.
DISTRIBUTION AND EXTENT: Valleys of southwestern Oregon; MLRA 5. This series is of small extent.
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 recognized include:
Mollic epipedon - from 0 to 18 inches (A, Bw horizons).
Entic feature - the Bw is part of the mollic and cannot qualify as cambic.
Particle-size control section - from 10 to 40 inches (part of Bw and C horizons) with weighted average of 73 percent rock fragments.