LOCATION TIMOSEA                 CA

Established Series
Rev. AFF-PWB-ET-MAV
12/2015

TIMOSEA SERIES


The Timosea series consists of very deep, well drained soils formed in alluvium from dominantly granitic sources. Timosea soils are on fan terraces and have slopes of 2 to 15 percent. The mean annual precipitation is about 6 inches and the mean annual temperature is about 59 degrees F.

TAXONOMIC CLASS: Loamy-skeletal, mixed, superactive, thermic Typic Haplargids

TYPICAL PEDON: Timosea gravelly sandy loam on a west-southwest facing slope of 7 percent under Cooper goldenbush, desert needlegrass and spiny hopsage at an elevation of 3,920 feet. (When described on April 3, 1984, the soil was dry throughout; colors are for dry soil unless otherwise stated).

A--0 to 4 inches; light yellowish brown (10YR 6/4) gravelly sandy loam, dark yellowish brown (10YR 4/4) moist; weak medium subangular blocky structure parting to weak thin and medium platy; soft, very friable, nonsticky and nonplastic; common very fine and few fine roots; common very fine and few fine and medium tubular pores; strongly effervescent; 20 percent pebbles, 5 percent cobbles and 5 percent stones; moderately alkaline (pH 8.0); clear wavy boundary. (3 to 10 inches thick)

AB--4 to 11 inches; light yellowish brown (10YR 6/4) gravelly sandy loam, dark yellowish brown (10YR 4/4) moist; weak fine and medium subangular blocky structure; slightly hard, very friable, nonsticky and nonplastic; common very fine and few fine and medium roots; common very fine and fine and few medium tubular pores; 15 percent pebbles, 10 percent cobbles and 5 percent stones; moderately alkaline (pH 8.1); clear wavy boundary. (0 to 10 inches thick)

Bt--11 to 19 inches; yellowish brown (10YR 5/4) very cobbly sandy clay loam, dark yellowish brown (10YR 4/4) moist; moderate fine and medium subangular blocky structure; hard, friable, slightly sticky and slightly plastic; common very fine and few fine and medium roots; many very fine and few fine and medium tubular pores; many thin clay films bridging mineral grains and in pores, common thin clay films on peds; 5 percent pebbles, 25 percent cobbles and 5 percent stones; moderately alkaline (pH 8.1); gradual wavy boundary.

Btk--19 to 44 inches; brownish yellow (10YR 6/6) very cobbly sandy clay loam, dark yellowish brown (10YR 4/4) moist; moderate fine and medium subangular blocky structure; very hard, firm, slightly sticky and plastic; common very fine and fine and few medium roots; common very fine and few fine tubular pores; many thin clay films on peds and in pores; matrix noneffervescent with carbonates segregated as common fine filaments and seams; 5 percent pebbles, 35 percent cobbles and 15 percent stones; moderately alkaline (pH 8.2); gradual wavy boundary. (Combined thickness of the Bt and Btk horizons is 18 to 35 inches thick)

BCtk--44 to 60 inches; brownish yellow (10YR 6/6) gravelly sandy loam, dark yellowish brown (10YR 4/4) moist; weak medium and coarse subangular blocky structure; hard, friable, slightly sticky and slightly plastic; few very fine and fine roots; common very fine and few fine tubular pores; many thin clay films bridging mineral grains and in pores, few thin clay films on peds; matrix noneffervescent with carbonates segregated as few fine filaments and seams; 15 percent pebbles and 5 percent cobbles; moderately alkaline (pH 8.0).

TYPE LOCATION: Inyo County, California; about 4.5 miles south of Olancha, 520 feet north and 400 feet east of the SW corner of Sec.4, T.20S., R.37E., M.D.B.M., Haiwee Reservoir NW quadrangle, and 150 feet west of Highway 395 and 50 feet south of Summit Creek Road.

RANGE IN CHARACTERISTICS: Thickness of the solum is 35 to 65 inches. The mean annual soil temperature is 61 to 66 degrees F The soil temperature is below 47 degrees F from about December 1 to March 1 and is below 41 degrees F from about January 1 to February 1. The soil between the depths of 12 and 38 inches is dry throughout for 210 to 235 days from about May 1 to December 15. It is moist throughout for 40 to 60 days from about January 15 to March 15 and is moist in some or all parts for 40 to 60 consecutive days from about March 1 to May 1 when the soil temperature exceeds 47 degrees F. The surface is covered with 15 to 70 percent rock fragments (many do not extend down into the A horizon) with 10 to 50 percent gravel, 2 to 15 percent cobbles, 0 to 12 percent stones, and 0 to 10 percent boulders. Reaction is slightly alkaline or moderately alkaline throughout. Electrical conductivity is 0 to 2 dS/m

The A horizon color is 10YR 5/3, 5/4, 6/2, 6/3, 6/4, or 7/3. Moist color is 10YR 3/3, 3/4, 4/2, 4/3 or 4/4. Those colors that are dark either do not have the organic carbon or the thickness to qualify for a mollic epipedon. It has 15 to 60 percent rock fragments with 5 to 35 percent gravel, 3 to 20 percent cobbles, 0 to 15 percent stones, and 0 to 20 percent boulders. The fine-earth fraction is loamy sand or sandy loam averaging 5 to 15 percent clay.

The Bt horizon color is 10YR 5/4, 5/6, 6/6, 7/4; 7.5YR 5/6, or 6/6. Moist color is 10YR 4/4, 4/6, 5/4, 5/6; or 7.5YR 4/6. It has 35 to 60 percent rock fragments with 5 to 45 percent gravel, 10 to 35 percent cobbles, and 0 to 30 percent stones and boulders. The fine earth fraction is sandy loam or sandy clay loam averaging 18 to 35 percent clay.

COMPETING SERIES: These are the Ashmed (T), Bitter, Bitter Spring, and Pinaleno series. Ashmed soils have solum thickness ranging from 25 to 41 inches. In addition rock fragments are 60 percent or more in the control section. Bitter soils have a 10 to 30-inch solum. Bitter Spring soils have a 5 to 10-inch solum. Pinaleno soils receive appreciable amounts of precipitation during summer months.

GEOGRAPHIC SETTING: Timosea soils are on fan terraces. Slopes are 2 to 15 percent. They formed in alluvium dominantly from granitic sources. Elevations are 3,700 to 4,200 feet. The climate is arid with hot dry summers, and cool, moist winters. Mean annual precipitation is 5 to 6 inches. Mean January temperature is about 40 degrees F, mean July temperature is about 81 degrees F; mean annual temperature is 57 to 61 degrees F. Frost-free season is 215 to 225 days.

GEOGRAPHICALLY ASSOCIATED SOILS: These are the Centennial (T), Helendale and Neuralia soils. Centennial soils are coarse-loamy and have a petrocalcic horizon. Helendale soils are coarse-loamy. Neuralia soils are fine-loamy. All of these soils are on fan terraces of nearby landscapes.

DRAINAGE AND PERMEABILITY: Well drained; slow and medium runoff; moderately slow permeability. In some areas the substratum has rapid permeability.

USE AND VEGETATION: Timosea soils are used for rangeland and wildlife habitat. Vegetation is desert needlegrass, spiny hopsage, white bursage, blackbrush and creosotebush.

DISTRIBUTION AND EXTENT: Southern Owens Valley of eastern California. The series is not extensive in MLRA 30.

MLRA SOIL SURVEY REGIONAL OFFICE (MO) RESPONSIBLE: PHOENIX, ARIZONA

SERIES PROPOSED: Benton-Owens Valley Area, Inyo County, California, 1989. Name from nearby Timosea Peak.

REMARKS: Major diagnostic horizons and other soil characteristics recognized in the profile are:

1. Ochric epipedon--0 to 11 inches (A, AB). Values are too high, or the epipedon is not thick enough to be mollic.

1.1 Organic carbon assumed less than 0.6%

2. Argillic horizon--11 to 60 inches (Bt, Btk, BCtk). Clay increase from 12 percent (AB) to 23 percent (Bt) to 26 percent (Btk) by field estimate and hydrometer. Clay films are present.

3. Thermic soil temperature regime -- assumption based on preliminary SCS soil temperature transect, 55 years local climatic records and BLM data.

4. Mineralogy -- assumed mixed; no indication otherwise.

5. Loamy-skeletal particle-size class -- based on field estimates, hydrometer, and rock fragment content.

6. Moisture regime - Aridic

Responsibility for this series was transferred from Davis to Phoenix 12/2015. The last revision to the series was 2/1997. ET


National Cooperative Soil Survey
U.S.A.