LOCATION NUMU CA

Established Series
Rev. ET-MAV
06/2016

NUMU SERIES

The Numu series consists of very deep, somewhat poorly drained soils that formed in alluvium from mixed sources, and lacustrine sediments. Numu soils are on stream and lacustrine terraces and have slopes of 0 to 2 percent. The mean annual precipitation is about 130 mm and the mean annual temperature is about 15 degrees C.

TAXONOMIC CLASS: Fine-loamy, mixed, superactive, thermic Durinodic Xeric Haplargids

TYPICAL PEDON: Numu fine sandy loam on a level stream terrace, under inland saltgrass and alkali sacaton at an elevation of 1,160 meters. (When described on May 2, 1985, the soil was moist to 84 cm, and wet below to 152 cm. Colors are for dry soil unless otherwise stated).

Anz1--0 to 10 cm; brown (7.5YR 5/4) fine sandy loam, dark brown (7.5YR 3/4) moist; weak medium and coarse subangular blocky structure; slightly hard, friable, slightly sticky and slightly plastic; common very fine and few fine and medium roots; common very fine and few fine tubular pores; violently effervescent; moderately alkaline (pH 8.4); clear smooth boundary. (5 to 15 cm thick).

Anz2--10 to 23 cm; brown (7.5YR 5/4) fine sandy loam, dark brown (7.5YR 3/4) moist; weak medium and coarse subangular blocky structure; slightly hard, friable, slightly sticky and slightly plastic; common very fine, and fine and few medium and coarse roots; many very fine and few fine tubular pores; violently effervescent; moderately alkaline (pH 8.2); clear smooth boundary. (8 to 18 cm thick).

Anz3--23 to 43 cm; brown (7.5YR 5/4) fine sandy loam, brown (7.5YR 4/4) moist; weak medium and coarse subangular blocky structure; slightly hard, very friable, slightly sticky and slightly plastic; common very fine, fine, medium and few coarse roots; many very fine and few fine tubular pores; violently effervescent; strongly alkaline (pH 8.6); clear smooth boundary. (13 to 25 cm thick).

Btnz--43 to 69 cm; pale brown (10YR 6/3) loam, brown (10YR 4/3) moist; weak coarse subangular blocky structure; hard, friable, sticky and plastic; common very fine and few fine and medium roots; many very fine and common fine tubular pores; common faint clay films in pores and few faint clay films bridging mineral grains and on faces of peds; strongly effervescent; 2 percent gravel; moderately alkaline (pH 8.4); clear smooth boundary. (20 to 30 cm thick).

Btqnz--69 to 84 cm; pale brown (10YR 6/3) clay loam, brown (10YR 4/3) moist; weak coarse subangular blocky structure; hard to very hard, firm to very firm, moderately sticky and plastic; common very fine and few fine and medium roots; many very fine and common fine tubular pores; common faint clay films in pores and few faint clay films bridging mineral grains and on faces of peds; 20 percent weakly cemented durinodes 5 to 25 mm in diameter; strongly effervescent; 2 percent gravel; moderately alkaline (pH 8.4); clear smooth boundary. (5 to 15 cm thick).

Btq--84 to 112 cm; light gray (2.5Y 7/2) clay loam, dark grayish brown (2.5Y 4/2) moist; weak coarse subangular blocky structure; hard to very hard, firm to very firm, moderately sticky and moderately plastic; few fine and very fine roots; common very fine tubular pores; common faint clay films in pores and few faint clay films bridging mineral grains and on faces of peds; 40 percent weakly cemented durinodes 5 to 25 mm in diameter; strongly effervescent; few fine prominent dark gray (10YR 4/1), black (10YR 2/1) moist masses of manganese accumulations lining pores and surrounding roots; 2 percent gravel; strongly alkaline (pH 8.7); clear smooth boundary. (18 to 36 cm thick).

2C--112 to 137 cm; light olive gray (5Y 6/2) clay, olive gray (5Y 4/2) moist; massive; very hard, firm, moderately sticky and very plastic; few very fine roots; few very fine tubular pores; common medium prominent dark gray (10YR 4/1), black (10YR 2/1) moist masses of manganese accumulations lining pores and surrounding roots; slightly alkaline (pH 7.6); abrupt smooth boundary. (0 to 36 cm thick).

3C--137 to 183 cm; light olive gray (5Y 6/2) loamy fine sand, olive gray (5Y 4/2) moist; massive; soft, very friable, nonsticky and nonplastic; many very fine interstitial pores; slightly acid (pH 6.2).

TYPE LOCATION: Inyo County, California; about 5.5 miles north of Independence; 2,200 feet west and 2,200 feet south of the northeast corner of Sec. 23, T. 12 S., R. 34 E.; USGS Blackrock 7.5 minute topographic quadrangle; latitude 36 degrees 53 minutes 33 seconds N and longitude 118 degrees 13 minutes 33 seconds W; WGS84 Decimal Degrees 36.8925000 latitude, -118.2258333 longitude.

RANGE IN CHARACTERISTICS: The thickness of the argillic is 43 to 81 cm. The mean annual soil temperature is 15 to 17.8 degrees C. The soil temperature is below 8.3 degrees C from about December 1 to March 1, and is below 5 degrees C from about January 1 to February 1. The soil between the depths of 18 and 36 cm is dry throughout for 200 to 225 days from about May 15 to December 15. It is moist throughout for 75 to 105 days from about January 15 to April 30 and is moist in some or all parts for 70 to 85 consecutive days from about March 1 to May 15 when the soil is above 8.3 degrees C. A water table is at a depth of 91 to 152 cm from March 1 to May 15. There is less than 5 percent gravel throughout.

The A horizon color is 2.5Y 6/2, 7/2; 7.5YR 5/2, 5/4; 10YR 5/2, 6/2, 6/3, 7/2 or 7/3. Moist color is 2.5Y 5/2, 4/4; 7.5YR 4/2, 3/4, 4/4; 10YR 3/2, 3/3, 5/3, 4/4, or 5/4. Textures are loamy sand, sandy loam, fine sandy loam or loam averaging 4 to 12 percent clay. Electrical conductivity is 16 to 30 decisiemens/meter and sodium adsorption ratio is greater than 45. Reaction is moderately or strongly alkaline.

The Bt horizon color is 2.5Y 7/2; 7.5YR 4/4, 5/4, 6/4 or 7/4; 10YR 6/2, 6/3, 7/2, or 7/3. Moist color is 2.5Y 4/4; 7.5YR 4/2, 4/4; 10YR 4/3, 5/3, or 5/4. Textures are loam or sandy loam averaging 18 to 27 percent clay. Electrical conductivity is 16 to 30 decisiemans/meter and sodium adsorption ratio is greater than 45. Reaction is moderately or strongly alkaline.

The Btq horizon color is 2.5Y 7/2, 8/2; 10YR 6/2, 6/3, 6/4 or 8/1. Moist color is 2.5Y 4/2, 6/2, 4/4; 10YR 4/2, 4/3, 4/4 or 6/2. Textures are loam, sandy clay loam or clay loam averaging 18 to 35 percent clay. It has 20 to 50 percent 5 to 25 mm durinodes. Electrical conductivity is 8 to 30 decisiemens/meter and sodium adsorption ratio is greater than 45. Reaction is moderately or strongly alkaline.

The 2C and 3C horizon color is 5Y 6/1, 6/2, 6/3, 7/2, or 7/3. Moist color is 5Y 4/2, 4/4, or 5/3. Textures are sand, loamy sand, loamy fine sand or loam averaging 4 to 12 percent clay in the lower part. The upper part is clay loam or clay averaging 35 to 50 percent clay. Some pedons have C horizons with similar colors and textures of the 2C or 3C.

COMPETING SERIES: There are no other series in this family. A similar soil in another family is the Winnedumah series. Winnedumah soils does not have a duric layer. Winnedumah soils are in similar landscape position.

GEOGRAPHIC SETTING: Numu soils are on stream and lacustrine terraces. Slopes are 0 to 2 percent. The soils formed in alluvium from mixed sources and lacustrine sediments. Elevations are 1,143 to 1,189 meters. The climate is hot dry summers with cool moist winters. The mean annual precipitation is 100 to 150 mm. The mean annual temperature is 15 to 16.1 degrees C. Mean July temperature is about 26.7 degrees C, and mean January temperature is about 4.4 degrees C. The frost-free season is 150 to 225 days.

GEOGRAPHICALLY ASSOCIATED SOILS ARE: Manzanar (T), Mazourka (T), Pokonahbe (T), Shondow (T) and Winnedumah soils. Manzanar soils do not have an argillic horizon; Mazourka soils have a coarse-loamy textural control section; Pokonahbe and Winnedumah soils do not have a duric layer; Shondow soils have a mollic epipedon. All these soils are on stream terraces.

DRAINAGE AND PERMEABILITY: Somewhat poorly drained; slow runoff; moderately slow permeability over slow and rapid in the stratified substratum. Moderately well drained phases are recognized.

USE AND VEGETATION: Numu soils are used for rangeland and wildlife habitat. Vegetation is inland saltgrass, alkali sacaton, black greasewood and shadscale.

DISTRIBUTION AND EXTENT: Owens Valley of east central California. The series is not extensive in MLRA 29.

MLRA SOIL SURVEY REGIONAL OFFICE (MO) RESPONSIBLE: Davis, California

SERIES PROPOSED: Benton-Owens Valley area, Inyo County, California, 1988. The name is taken from the Mono Indian tribe meaning "the people".

REMARKS: The electrical conductivity can be as high as 200 decisiemens/meter on the surface and the sodium adsorption ratio can be as high as 600 within the profile.

Diagnostic horizons and features recognized in this pedon are:

1. Ochric epipedon - 0 to 43 cm (A)

2. Argillic horizon -- 43 to 112 cm (Bt, Btq1, Btq2)

2.1 Clay content increases greater than 1.2 times to A horizon

2.2 Common faint clay films in pores and on ped faces

3. Duric horizon--69 to 112 cm (Btq1, Btq2).

4. Thermic temperature regime -- mean annual soil temperature 15 to 17.8 degrees C local climatic data.

5. Mineralogy -- assumed mixed

6. Particle Size Class -- fine-loamy.

7. Moisture Regime - Aridic bordering on Xeric

7.1 The moisture control section is dry throughout from May 15 to December 15. It is moist in some or all parts from about March 1 to May 15 when the soil is above 8.3 degrees C.

7.2 The soil temperature exceeds 5 degrees C from February 1 to January 1 (335 days). Within this time period the moisture control section is dry from May 15 to December 15 (214 days).

7.3 The soil temperature exceeds 8.3 degrees C from March 1 to December 1 (275 days). Within this time period the moisture control section is dry from about May 15 to December 15 (214 days).

National Cooperative Soil Survey
U.S.A.