LOCATION HILLTISH OREstablished Series
TAXONOMIC CLASS: Loamy-skeletal, mixed, superactive, mesic Typic Dystroxerepts
TYPICAL PEDON: Hilltish very gravelly sandy loam - forested, 55 percent slope at an elevation of 1600 feet. (Colors are moist soil unless otherwise noted)
A--0 to 2 inches; dark brown (10YR 3/3) very gravelly sandy loam, brown (10YR 4/3) dry; moderate medium and fine granular structure; soft, friable, nonsticky and nonplastic; many very fine and fine roots; many medium irregular pores; 30 percent gravel and 5 percent cobbles; slightly acid (pH 6.4); abrupt smooth boundary. (2 to 9 inches thick)
AB--2 to 4 inches; dark brown (10YR 3/3) very gravelly sandy loam, brown (10YR 5/3) dry; weak fine and medium granular structure; soft, friable, nonsticky and nonplastic; many very fine, fine, and medium roots; many medium irregular pores; 40 percent gravel and 5 percent cobbles; moderately acid (pH 6.0); clear smooth boundary. (0 to 4 inches thick)
Bw1--4 to 9 inches; brown (10YR 4/3) very gravelly sandy loam, brown (10YR 5/3) dry; moderate fine and medium subangular blocky structure; slightly hard, friable, nonsticky and nonplastic; many very fine and fine and common medium roots; common medium irregular and tubular pores; 35 percent gravel and 5 percent cobbles; moderately acid (pH 5.8); clear smooth boundary.
Bw2--9 to 14 inches; brown (7.5YR 5/3) very gravelly sandy loam, pale brown (10YR 6/3) dry; weak fine and medium subangular blocky structure; slightly hard, friable, slightly sticky and slightly plastic; common very fine, fine, and medium roots; common fine irregular and tubular pores; 30 percent gravel and 5 percent cobbles; moderately acid (pH 5.8); clear smooth boundary. (Combined thickness of the Bw horizon is 10 to 27 inches)
BC--14 to 18 inches; brown (7.5YR 5/3) extremely cobbly sandy loam, light brown (7.5YR 6/3) dry; weak fine and medium subangular blocky structure; hard, friable, nonsticky and nonplastic; common very fine, fine, and medium roots; many medium irregular and tubular pores; 35 percent gravel and 30 percent cobbles; moderately acid (pH 5.8); gradual wavy boundary. (0 to 7 inches thick)
C--18 to 27 inches; reddish yellow (7.5YR 6/6) extremely cobbly sandy loam, pink (7.5YR 7/4) dry; massive; hard, friable, nonsticky and nonplastic; few very fine, fine, and medium roots; few medium irregular pores; 40 percent gravel and 30 percent cobbles; moderately acid (pH 5.6); clear smooth boundary. (8 to 16 inches thick)
R--27 inches; conglomerate
TYPE LOCATION: Douglas County, Oregon, about 2 miles south of the town of Myrtle Creek, about 1500 feet south and 1750 feet east of the northeast corner of section 3, T.30S., R.5 W. (Latitude 42 degrees, 59 minutes, 40 seconds N, Longitude 123 degrees, 16 minutes, 35 seconds W)
RANGE IN CHARACTERISTICS: These soils are usually moist but are dry in the moisture control section for 60 to 90 consecutive days in the four months that follow the summer solstice. The mean annual soil temperature is 51 to 56 degrees F. Depth to bedrock is 20 to 40 inches. The particle-size control section has 10 to 22 percent clay, 30 to 50 percent gravel, and 5 to 30 percent cobbles. Rock fragments are rounded.
The A and AB horizons have a value of 3 to 5 moist, 4 to 6 dry, and chroma of 2 to 4 moist and dry. It has 30 to 50 percent gravel and 5 to 15 percent cobbles.
The Bw horizon has a hue of 10YR or 7.5YR, value of 4 to 6 moist, 5 to 7 dry, and chroma of 3 to 6 moist and dry. It is very gravelly sandy loam, extremely gravelly sandy loam, or very gravelly coarse sandy loam. It has 30 to 50 percent gravel and 5 to 20 percent cobbles. It is moderately or slightly acid.
The BC and C horizons have a hue of 10YR or 7.5YR, value of 4 to 6 moist, 5 to 7 dry, and chroma of 3 to 6 moist and dry. It is very gravelly sandy loam, very gravelly sandy clay loam, or extremely cobbly sandy loam. It has 30 to 45 percent gravel and 5 to 30 percent cobbles. It is strongly or moderately acid.
COMPETING SERIES: These are the Atring, Baldhill, Barpeak, Beekman, Clallam, Farber, Geppert, Hartless, Inskip, Kanid, Kindig, Mayacama, Neuns, Sheetiron, Straight, Terbies, Vena and Woodin series. Atring soils are dry 45 to 60 days and have angular rock fragments in the particle-size control section and have a paralithic contact. Baldhill, Barpeak, and Farber soils are greater than 60 inches to bedrock. Geppert and Straight soils have a paralithic contact. In addition, Straight soils have hue of 5YR or 2.5YR. Clallam soils are moderately well drained and have a paralithic contact. Hartless, Kanid, Kindig, and Terbies soils are greater than 40 inches to bedrock. Inskip soils have less than 10 percent clay in the particle-size control section. Mayacama soils are dry for 120 days. Neuns, Sheetiron, and Woodin soils are dry for more than 90 consecutive days. Beekman and Vena soils contain angular rock fragments. Beekman soils are over metasedimentary and metavolcanic rocks. Vena soils are formed over rhyolitic tuff.
GEOGRAPHIC SETTING: Hilltish soils are on hills and mountain side slopes. The soils formed in conglomerate from the Riddle Formation. Slopes are 30 to 90 percent. Elevations are 700 to 2900 feet. The climate is characterized by warm, wet winters and hot, dry summers. The mean annual temperature is 50 to 55 degrees F. The mean annual precipitation is 30 to 40 inches. The frost-free period is 150 to 200 days.
GEOGRAPHICALLY ASSOCIATED SOILS: These are the competing Beekman soils and the Brader, Debenger, Josephine, Speaker, Sutherlin, and Vermisa soils. Brader soils are less than 20 inches to bedrock and on convex side slopes. Debenger and Speaker soils have less than 35 percent rock fragments and are on convex side slopes. Josephine soils are more than 40 inches to bedrock and on concave side slopes. Sutherlin soils are fine-silty over clayey and are on concave side slopes. Vermisa soils are less than 20 to bedrock and are primarily on slopes over 60 percent.
DRAINAGE AND PERMEABILITY: Well drained; moderately rapid permeability.
USE AND VEGETATION: Hilltish soils are used for timber production, water supply, and wildlife habitat. Natural vegetation is Douglas fir, ponderosa pine, Pacific madrone, whipplevine, tall Oregongrape, hairy honeysuckle, common snowberry, Pacific poison oak, canyon live oak, and California fescue.
DISTRIBUTION AND EXTENT: Southwestern Oregon, MLRA 5. The series is not extensive.
MLRA SOIL SURVEY REGIONAL OFFICE (MO) RESPONSIBLE: Davis, California
SERIES ESTABLISHED: Douglas County, Oregon, 1994.
REMARKS: Diagnostic horizons and features recognized in this pedon are:
Ochric epipedon-
Cambic horizon - from 4 to 14 inches (Bw1 and Bw2 horizons).
Particle-size control section - from 10 to 27 inches.
The assumed base saturation (ammonium acetate) between 10 and 30 inches is less than 60 percent.
Series limited to conglomerates of the Riddle Formation
Classification revised from loamy-skeletal, mixed, mesic Dystric Xerochrepts 6/99