LOCATION TAMFLAT CAEstablished Series
TAXONOMIC CLASS: Clayey-skeletal, magnesic, frigid Lithic Haploxeralfs
TYPICAL PEDON: Tamflat very cobbly loam-on an east-southeast facing slope of 65 percent under a cover of Fremont silktassel, huckleberry oak, wedgeleaf ceanothus. scattered Jeffrey pine and Incense-cedar at 6,000 feet elevation. (Colors are for dry soil unless otherwise stated. When described 8/13/80 the soil was dry to 11 inches and moist below.)
0--1 inch to 0; loose needles and litter cover 30 percent of surface. (O to 2 inches thick)
A--0 to 1 inch; brown (7.5YR 4/4) very cobbly loam, dark reddish brown (5YR 3/3) moist; moderate thin and medium platy structure; slightly hard, friable, nonsticky and nonplastic; common very fine roots; common fine interstitial pores; 28 percent pebbles, 30 percent cobbles; neutral (pH 7.0); abrupt smooth boundary. (1 to 8 inches thick)
BAt--1 to 10 inches; yellowish red (5YR 5/6) extremely gravelly clay loam, yellowish red (5YR 4/6) moist; moderate medium and fine subangular blocky structure; hard, firm, sticky and plastic; common very fine, few fine and medium roots; common fine interstitial pores; few thin and moderately thick clay films on peds; 57 percent pebbles. 5 percent cobbles; mildly alkaline (pH 7.5); clear wavy boundary. (5 to 10 inches thick)
Bt--10 to 19 inches; strong brown (7.5YR 4/6) extremely gravelly clay, strong brown (7.5YR 4/6) moist; strong fine subangular blocky structure; hard, very firm, slightly sticky and very plastic; few fine, medium and coarse roots; few fine interstitial and tubular pores; continuous thick clay films on peds and in pores; 53 percent pebbles, 25 percent cobbles; neutral (pH 7.2); abrupt irregular boundary. (4 to 10 inches thick)
R--19 to 24 inches; highly fractured peridotite rock.
TYPE LOCATION: Siskiyou County. California; about 6 miles southwest of Weed and 2.5 miles south of Stewart Springs; 3/4 to 1 mile up side road from Eddy Creek Road; hand dug pit at top of road cut about 2,200 feet east of the center section 23, T.41N., R.6W.
RANGE IN CHARACTERISTICS: The thickness of the solum and depth to bedrock ranges from 10 to 20 inches. Rock fragments consist of pebbles, cobbles, and stones and average 35 to 85 percent of the soil. The soil is usually moist between 14 inches and bedrock but is dry in all parts from early August to early October. The base saturation is about 70 to 90 percent immediately above a lithic contact. The mean annual soil temperature ranges from 40 degrees to 47 degrees F.
The A horizon has color of 10YR 5/3; 7.5YR 4/4, 5/4, 5/6, or 5YR 4/6 and moist color of 10YR 3/3; 7.5YR 3/4, 4/6, 3/4; 5YR 3/3, 4/4, or 3/4. It is loam or clay loam with 20 to 35 percent clay, modified by 35 to 60 percent rock fragments. It is neutral or mildly alkaline. Only the upper 1 to 3 inches have the dark colors of a mollic epipedon.
The Bt horizon has color of 10YR 6/6; 7.5YR 4/6, 5/6, 4/4; 5YR 5/6 or 5YR 4/4 and moist color of 10YR 4/4; 7.5YR 4/6, 5/4, 6/6; 5YR 3/4, 4/4 or 5/6. It is heavy clay loam or clay with 35 to 60 percent clay modified by 60 to 85 percent rock fragments. It is neutral or mildly alkaline.
COMPETING SERIES: There are no other series in this family.
GEOGRAPHIC SETTING: Tamflat soils are on uplands and have slopes of 20 to 70 percent. Tamflat soils formed in material weathered from ultramafic rocks, mostly peridotite. Rock outcrop ranges from 5 to 15 percent. Elevation ranges from 4,000 to 6,000 feet. The climate is Canadian with warm, dry summers and cold, moist winters. The average annual precipitation ranges from 40 to 60 inches. Mean annual temperature ranges from 47 degrees to 44 degrees F. Mean January temperature is 28 degrees F. and the mean July temperature is 63 degrees F. The average frost-free season is 80 to 150 days.
GEOGRAPHICALLY ASSOCIATED SOILS: See remarks.
DRAINAGE AND PERMEABILITY: Well drained; moderate to very rapid run-off; slow permeability.
USE AND VEGETATION: Wildlife habitat and watershed; natural vegetation is huckle-berry oak, wedgeleaf ceanothus, Fremont silktassel, rabbitbrush, a few scattered Jeffrey pine, incense-cedar and Douglas-fir.
DISTRIBUTION AND EXTENT: the higher elevations of the Klamath Mountains of northern California and possibly southern Oregon. The soils of this series are of small extent, about 5,000 acres.
MLRA SOIL SURVEY REGIONAL OFFICE (MO) RESPONSIBLE: Davis, California
SERIES ESTABLISHED: Siskiyou County, California, Shasta-Trinity National Forest, 1981.
REMARKS: This series is being established to map a new family in an area where map unit components were classified only to the family level.
ADDITIONAL DATA: NSSL S81CA-93-3.
OSED scanned by SSQA. Last revised by state on 5/83.