LOCATION SED                     NV

Established Series
Rev. JR/TM/ET
12/2015

SED SERIES

The Sed series consists of moderately deep, well drained soils on mountain shoulders and summits. Sed soil formed in residuum from quartzite, tuff or rhyolite. Slopes are 15 to 50 percent. The mean annual precipitation is about 13 inches and the mean annual temperature is about 50 degrees F.

TAXONOMIC CLASS: Loamy-skeletal, mixed, superactive, mesic Ustic Haplargids

TYPICAL PEDON: Sed very gravelly loam - woodland. (Colors are for dry soil unless otherwise noted). The soil surface is partially covered with 30 percent pebbles and 15 percent cobbles.

A1--0 to 3 inches; pale brown (10YR 6/3) very gravelly loam, brown (10YR 4/3) moist; weak coarse platy structure; soft, very friable, slightly sticky and slightly plastic; common very fine and fine roots; common very fine tubular pores; 45 percent pebbles; slightly alkaline (pH 7.8); abrupt wavy boundary. (2 to 6 inches thick)

A2--3 to 7 inches; pale brown (10YR 6/3) gravelly loam, brown (10YR 4/3) moist; weak medium subangular blocky structure; soft, very friable, slightly sticky and slightly plastic; common medium and coarse, few very coarse roots; common fine and medium tubular pores; 15 percent pebbles; moderately alkaline (pH 8.0); clear wavy boundary. (0 to 7 inches thick)

Bt1--7 to 20 inches; brown (10YR 5/3) very gravelly loam, dark brown (10YR 4/3) moist; moderate medium subangular blocky structure; slightly hard, friable, slightly sticky and slightly plastic; few medium and coarse, common very fine and fine roots; common fine and medium tubular pores; common distinct clay films on faces of peds; 35 percent pebbles; moderately alkaline (pH 8.0); clear wavy boundary. (10 to 17 inches thick)

Bt2--20 to 24 inches; light yellowish brown (10YR 6/4) extremely stony clay loam, yellowish brown (10YR 5/4) moist; weak fine subangular blocky structure; slightly hard, friable, slightly sticky and slightly plastic; few very fine, common medium and coarse roots; common medium and coarse interstitial and common fine tubular pores; few fine distinct clay films on faces of ped; 30 percent pebbles 10 percent cobbles and 25 percent stones; moderately alkaline (pH 8.0); abrupt wavy boundary. (3 to 10 inches thick)

R--24 inches; extremely hard fractured quartzite bedrock.

TYPE LOCATION: Nye County, Nevada; in the Spring Mountains approximately 10 miles north of Pahrump and about 1,500 feet south and 1,000 feet east of the northwest corner of section 25, T. 17 S., R. 53 E.

RANGE IN CHARACTERISTICS:

Soil moisture - Usually dry, moist during winter and early spring and for brief periods July through October following summer convection storms.
Soil temperature - 53 to 58 degrees.
Depth to bedrock - 20 to 40 inches.

Control section - Clay content: 20 to 30 percent.
Rock fragments: Averages 40 to 60 percent.

A horizon - Value: 5 or 6 dry, 4 or 5 moist.
Reaction: Mildly alkaline or moderately alkaline.

Bt horizon - Value: 5 or 6 dry, 4 or 5 moist.
Chroma: 3 or 4.
Structure: Subangular blocky or is massive.
Texture: Very gravelly loam or very gravelly clay loam, in upper part, extremely stony clay loam or extremely stony loam in lower part.
Consistence: Slightly sticky or moderately sticky and slightly plastic or moderately plastic

COMPETING SERIES: These are the Elements (T AZ), Larim (WY), Musofare (NM), Romberg (MT), Saemo (AZ), Sedillo (NM) and Tacan (UT) soils. Larim, Romberg, Sedillo and Tacan soils lack bedrock within 40 inches. Musofare soils have hues of 7.5YR or 5YR and have calcic horizons.

GEOGRAPHIC SETTING: Sed soils are on mountain shoulders and summits. These soils formed in residuum from quartzite, tuff, or rhyolite. Slopes are 15 to 50 percent. Elevations are 5,600 to 8,100 feet. The climate is cool, semiarid with cold winters and warm summers. The mean annual precipitation is 10 to 14 inches; mean annual temperature is 51 to 57 degrees F., and the frost-free season is 130 to 180 days.

GEOGRAPHICALLY ASSOCIATED SOILS: These are the Zibate soils. Zibate soils are shallower than 20 inches to bedrock. They are found at lower elevations and on south facing slopes.

DRAINAGE AND PERMEABILITY: Well drained. Moderately rapid runoff; moderately slow permeability.

USE AND VEGETATION: Woodland and wildlife habitat. The present vegetation is mainly Wyoming big sagebrush, blue grama, pine bluegrass, singleleaf pinyon, and Utah juniper.

DISTRIBUTION AND EXTENT: Southern Nevada. These soils are not extensive. MLRA 30.

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

SERIES ESTABLISHED: Nye County, Nevada (Southwest Part), 1994. The name is coined.

REMARKS: Diagnostic horizons and features recognized in this pedon are:
Ochric epipedon - The zone from about 0 to 7 inches (A1 and A2 horizons)
Argillic horizon - The zone from about 7 to 24 inches (Bt1 and Bt2 horizons).
Ustic feature- The soil moisture regime is Aridic bordering Ustic.
Lithic contact - The boundary between the soil and bedrock at about 24 inches.

Responsibility for this series was transferred from Davis to Phoenix 12/2015. The last revision to the series was 8/2001. ET

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National Cooperative Soil Survey
U.S.A.