LOCATION CALFRANCH OREstablished Series
TAXONOMIC CLASS: Loamy-skeletal, mixed, active, isomesic Typic Dystrudepts
TYPICAL PEDON: Calfranch very channery loam - woodland, on a 45 percent southwest-facing slope at an elevation of 220 feet. (When described on October 18, 1990 the soil profile was moist to a depth of 12 inches and dry below this depth. Colors are for moist soil unless otherwise noted.)
Oi--0 to 3 inches; partially decomposed needles, leaves, twigs and woody materials.
A1--3 to 7 inches; brown (10YR 4/3) very channery loam, grayish brown (10YR 5/2) dry; weak fine subangular blocky structure; slightly hard, friable, nonsticky and nonplastic; many very fine and fine, and common medium and coarse roots; common fine and very fine tubular pores; 35 percent channers; moderately acid (pH 5.6); clear smooth boundary.
A2--7 to 15 inches; dark yellowish brown (10YR 4/4) very channery loam, light yellowish brown (10YR 6/4) dry; weak fine subangular blocky structure; slightly hard, friable, slightly sticky and slightly plastic; many very fine and fine, and common medium and coarse roots; many fine tubular pores; 35 percent channers and 5 percent flagstones; moderately acid (pH 6.0); clear wavy boundary. (Combined thickness of the A horizon is 10 to 16 inches)
Bw1--15 to 20 inches; light olive brown (2.5Y 5/4) very channery loam, pale yellow (2.5Y 7/3) dry; weak fine and medium subangular blocky structure; slightly hard, friable, slightly sticky and slightly plastic; many fine and medium, and few coarse roots; common fine tubular pores; 35 percent channers and 10 percent flagstones; moderately acid (pH 5.7); clear wavy boundary.
Bw2--20 to 32 inches; light yellowish brown (2.5Y 6/3) very channery sandy loam, light gray (2.5Y 7/2) dry; weak fine and medium subangular blocky structure; slightly hard, friable, slightly sticky and slightly plastic; common fine and medium, and few coarse roots; common fine tubular pores; 40 percent channers and 15 percent flagstones; strongly acid (pH 5.2); clear wavy boundary.
Bw3--32 to 45 inches; light yellowish brown (2.5Y 6/3) extremely flaggy sandy loam, light gray (2.5Y 7/2) dry; weak fine subangular blocky structure; slightly hard, friable, slightly sticky and slightly plastic; common fine and medium, and few coarse roots; common fine tubular pores; 40 percent channers and 25 percent flagstones; very strongly acid (pH 4.9); gradual wavy boundary. (Combined thickness of the Bw horizon is 30 to 44 inches)
C1--45 to 58 inches; pale olive (5Y 6/3) extremely flaggy sandy loam, light gray (5Y 7/2) dry; massive; slightly hard, friable, slightly sticky and slightly plastic; few fine tubular pores; 50 percent channers and 25 percent flagstones; very strongly acid (pH 4.8); clear wavy boundary. (10 to 15 inches thick)
C2--58 to 70 inches; pale olive (5Y 6/3) extremely flaggy sandy loam, pale yellow (5Y 7/3) dry; massive; slightly hard, friable, slightly sticky and slightly plastic; few fine tubular pores; 50 percent channers and 25 percent flagstones; very strongly acid (pH 4.8).
TYPE LOCATION: Curry County, Oregon; located about 2,970 feet south and 2,450 feet west of the northeast corner of section 33, T. 35 S., R. 13 W. (Latitude 42 degrees, 30 minutes, 07 seconds N.; Longitude 124 degrees, 14 minutes, 59 seconds W.)
RANGE IN CHARACTERISTICS: The mean annual soil temperature is 51 to 54 degrees F. The difference between mean summer and mean winter soil temperature varies from 5 to 9 degrees F. The soils are usually moist but are dry less than 45 consecutive days between 4 and 12 inches in the four months following the summer solstice. The particle-size control section averages 10 to 20 percent clay and has 45 to 85 percent total rock fragments. Depth to bedrock is greater than 60 inches. Solum thickness is 40 to 60 inches.
The A horizon has value of 4 or 5 moist, 5 or 6 dry and chroma of 2 through 4 moist and dry. It is very channery loam with l5 to 25 percent clay. It has 35 to 50 percent channers and 0 to 5 percent flagstones. It is strongly or moderately acid.
The Bw horizon has hue of 10YR or 2.5Y, value of 5 or 6 moist, 6 or 7 dry and chroma of 2 through 4 moist and dry. It is very channery loam, very channery sandy loam, or extremely flaggy sandy loam with 10 to 20 percent clay. It has 35 to 50 percent channers and 10 to 30 percent flagstones. It is strongly or moderately acid.
The C horizon has hue of 2.5Y or 5Y, value of 6 or 7 moist, 7 or 8 dry and chroma of 2 through 4 moist and dry. It is very channery loam, extremely channery sandy loam, or extremely flaggy sandy loam with 10 to 20 percent clay. It has 40 to 55 percent channers and 15 to 30 percent flagstones. It is very strongly or strongly acid.
COMPETING SERIES: These are the Capeblanco, Dulandy, Lackscreek, and Slidecreek series. Capeblanco and lackscreek soils are 20 to 40 inches deep to bedrock. Dulandy and Lackscreek soils have a mean annual soil temperature greater than 54 degrees F. Slidecreek soils contain 25 to 35 percent clay in the particle-size control section.
GEOGRAPHIC SETTING: Calfranch soils occur on metastable broad ridgetops and slump benches, and on metastable to active side slopes of coastal hills and mountains. Slopes are 0 to 90 percent. The soils formed in colluvium and residuum derived from schist or phyllite rock types of the Colebrooke Schist Formation. Elevations are 100 to 1,000 feet. The climate is characterized by cool, wet winters and cool, moist summers with fog. A strong marine influence limits the diurnal and annual range of temperature. The mean annual precipitation is 75 to 95 inches. The mean annual temperature is 50 to 53 degrees F. The frost-free period is 200 to 270 days.
GEOGRAPHICALLY ASSOCIATED SOILS: These are the Desons, Watches, and the competing Capeblanco soils. All of these soils occur on broad ridgetops, benches, or side slopes of coastal hills and mountains. Desons soils have an argillic horizon. Watches soils are fine-loamy.
DRAINAGE AND PERMEABILITY: Well drained; moderately rapid permeability.
USE AND VEGETATION: Calfranch soils are used for timber production, watershed, recreation, and wildlife habitat. The native vegetation is Douglas fir, western hemlock, grand fir, Sitka spruce, red alder, tanoak, Pacific madrone, cascade Oregongrape, salal, Pacific rhododendron, evergreen huckleberry, western swordfern, common beargrass, red elderberry, and salmonberry.
DISTRIBUTION AND EXTENT: Coastal hills and mountains of southwestern Oregon; MLRA 1. The series is not extensive.
MLRA SOIL SURVEY REGIONAL OFFICE (MO) RESPONSIBLE: Portland, Oregon
SERIES ESTABLISHED: Curry County, Oregon; 1995. The source of the name is from Calf Ranch Mountain in northern Curry County.
REMARKS: Diagnostic horizons and features recognized in this pedon include:
Ochric epipedon.
Cambic horizon - from a depth of 15 to 45 inches (Bw1, Bw2, and Bw3 horizons).
Particle-size control section - from 10 to 40 inches (part of the A2, Bw1, the Bw2, and part of the Bw3 horizons) with a weighted average of 55 percent rock fragments.
All diagnostic horizons and features are measured from the to of the first mineral horizon.
ADDITIONAL DATA: Partial laboratory data available for pedon 91P 330, samples 91P1969-1973 from Curry County, Oregon sampled by NSSL, Lincoln NE - 4/15/92.