LOCATION PINEHURST OR+CAEstablished Series
TAXONOMIC CLASS: Fine-loamy, mixed, superactive, frigid Pachic Ultic Argixerolls
TYPICAL PEDON: Pinehurst loam - forested. (Colors are for moist soil unless otherwise noted.)
Oi--1 inch to 0; organic litter of needles and twigs.
A1--0 to 4 inches; dark reddish brown (5YR 2/2) loam, dark brown (7.5YR 3/3) dry; moderate very fine granular structure; slightly hard, friable, slightly sticky and slightly plastic; common fine and very fine roots; many irregular pores; 10 percent gravel; slightly acid (pH 6.4); clear smooth boundary. (2 to 6 inches thick)
A2--4 to 15 inches; dark reddish brown (5YR 2/2), crushed (10YR 3/2) loam, dark reddish brown (5YR 3/3) dry; moderate very fine subangular blocky structure; slightly hard, friable, slightly sticky and slightly plastic; common fine and coarse roots; many very fine tubular pores; 10 percent gravel; slightly acid (pH 6.2); clear smooth boundary. (0 to 12 inches thick)
BAt--15 to 21 inches; dark reddish brown (5YR 3/3) clay loam, reddish brown (5YR 4/3) dry; moderate very fine and fine subangular blocky structure; hard, friable, sticky and plastic; common fine and coarse roots; many very fine tubular pores; few faint clay films; 10 percent gravel; moderately acid (pH 6.0); clear wavy boundary. (0 to 8 inches thick)
Bt--21 to 41 inches; dark reddish brown (5YR 3/4) clay loam, reddish brown (5YR 4/4) rubbed, dark brown (7.5YR 4/4) dry; moderate medium subangular blocky structure; hard, firm, sticky and plastic; few medium and coarse roots; many very fine tubular pores; common faint clay films; 10 percent partially weathered gravel; moderately acid (pH 5.8); gradual wavy boundary. (14 to 30 inches thick)
BCt--41 to 60 inches; dark reddish brown (5YR 3/4) clay loam, brown (7.5YR 5/4) dry; weak coarse subangular blocky structure; hard, friable, sticky and plastic; few roots; common very fine tubular pores; few faint clay films; 5 percent partially weathered gravel and 10 percent partially weathered cobbles; strongly acid (pH 5.4).
TYPE LOCATION: Jackson County, Oregon; about 3/4 mile east of Hyatt Reservoir; 600 feet north and 500 feet west of the SE corner sec. 11, T. 39 S., R. 3 E., W.M.
RANGE IN CHARACTERISTICS: The soil is usually moist but is dry during the summer months for 45 to 70 consecutive days or more in all parts between 4 and 12 inches. The mean annual soil temperature is 42 to 47 degrees F. Base saturation is less than 75 percent in some parts of the upper 30 inches of the solum. Depth to bedrock ranges from 40 to 60 inches or more. There is a stone line at the upper boundary of the Bt horizon in some pedons. The mollic epipedon is 20 to 30 inches thick.
The A horizon has hue of 10YR, 7.5YR, or 5YR, value of 2 or 3 moist, 3 through 5 dry, and chroma of 2 or 3 moist and 2 through 4 dry. It is loam or stony loam. It has 15 to 25 percent clay. It has 0 to 20 percent stones and cobbles and 0 to 15 percent gravel. It has 2 to 4 percent organic matter.
The Bt horizon has hue of 5YR, 7.5YR, or 10YR, value of 3 through 5 moist, 4 through 6 dry, and chroma of 2 through 4 moist and dry. It is loam or clay loam with 20 to 35 percent clay and partially weathered rock fragments ranging from 5 to 25 percent gravel and 0 to 10 percent cobbles or stones. The upper 20 inches of the argillic horizon has less than 35 percent rock fragments. The lower part is very stony in some pedons. It is strongly or moderately acid.
COMPETING SERIES: These are the Bauscher, Brinegar, Bringmee, De Masters and Watchabob series. Bauscher soils lack an O horizon, are slightly acid, have formed in weathered granite and are high in medium and coarse sands and are coarse sandy loam in the lower part of the argillic horizon and the C horizon. Brinegar soils have a water table at depths of 36 inches in early spring, depth to mottles ranges from 30 to 45 inches, and lack an O horizon. De Masters soils lack an O horizon, have a mollic epipedon 30 to 55 inches thick. Bringmee soils lack an O horizon, are moderately acid to neutral and have significant amounts of ash in the upper part of the argillic horizon. Watchabob soils are 20 to 40 inches to a lithic contact.
GEOGRAPHIC SETTING: Pinehurst soils are on alluvial fans, hillslopes, pediment slopes and saddles at elevations of 3,400 to 6,000 feet. Slopes are 1 to 50 percent. The soils formed in mixed colluvium weathered from andesite, volcanic breccia, or tuffs. Summers are cool and dry and winters are cold and moist. The mean annual precipitation is 20 to 55 inches. The annual temperature is 40 to 46 degrees F. The frost-free period is less than 100 days.
GEOGRAPHICALLY ASSOCIATED SOILS: These are the Bogus, Farva, Greystoke, Iller and Sheld soils. Bogus soils have a fine-textured argillic horizon. Farva soils are moderately deep and have more than 35 percent rock fragments in the control section. Iller and Sheld soils are dominated by ash and have more than 35 percent rock fragments in the control section. Greystoke soils have more than 35 percent rock fragments in the control section.
DRAINAGE AND PERMEABILITY: Well drained; slow to rapid runoff; moderately slow permeability.
USE AND VEGETATION: Soils are used for timber production, grazing, water supply, recreation, wildlife, and building sites. Native vegetation is mainly Douglas fir, white fir, Pacific Yew, snowberry, serviceberry, and bunchgrass.
DISTRIBUTION AND EXTENT: Southern Cascades of Southwestern Oregon and in Northern California. The soils are of moderate extent.
MLRA SOIL SURVEY REGIONAL OFFICE (MO) RESPONSIBLE: Davis, California
SERIES ESTABLISHED: Siskiyou County, California, 1978.
REMARKS: The activity class was added to the classification in March of 2003. Competing series were not checked at that time. - ET