LOCATION PITTMAN                 NV

Established Series
REV: RLS/RPZ
12/2015

PITTMAN SERIES

The Pittman series consists of well drained soils that are moderately deep to a lime-cemented hardpan. They formed in alluvium from mostly igneous rock sources on erosional fan remnants and nonburied fan remnants. Slopes are 2 to 8 percent. The mean annual temperature is about 66 degrees F.; and the mean annual precipitation is about 5 inches.

TAXONOMIC CLASS: Sandy-skeletal, mixed, thermic Typic Petrocalcids

TYPICAL PEDON: Pittman extremely cobbly fine sandy loam - desert wildlife habitat (Colors are for dry soil unless otherwise noted.) (60 percent pebbbles and 20 percent cobbles on soil surface)

A--0 to 2 inches; pale brown (10YR 6/3) extremely cobbly fine sandy loam, dark brown (10YR 3/3) moist; weak thin platy structure; soft, very friable, nonsticky and nonplastic; common very fine roots; many very fine vesicular pores; 40 percent pebbles and 25 percent cobbles; slightly alkaline (pH 7.8); abrupt smooth boundary. (l to 4 inches thick)

Cl--2 to 6 inches; light brown (7.5YR 6/4) gravelly loam, brown (7.5YR 4/4) moist; very weak medium subangular blocky structure; slightly hard, very friable, nonsticky and slightly plastic; common very fine and few fine roots; 30 percent pebbles; moderately alkaline (pH 8.0); clear wavy boundary. (3 to 8 inches thick)

C2--6 to l9 inches; light brown (7.5YR 6/4) extremely gravelly loamy sand, brown (7.5YR 5/4) moist; massive; soft, very friable, nonsticky and nonplastic; many very fine,and few fine and medium roots; many very fine and fine interstitial pores; 50 percent pebbles and l5 percent cobbles; moderately alkaline (pH 8.0); clear wavy boundary. (l0 to l3 inches thick)

Ckl--l9 to 23 inches; light brown (7.5YR 6/4) extremely gravelly coarse sand, brown (7.5YR 4/4) moist; massive; slightly hard, very friable, nonsticky and nonplastic; common medium roots; many very fine and fine interstitial pores; 65 percent pebbles and l percent cobbles; very weakly lime-cemented; moderately alkaline (pH 8.0); abrupt wavy boundary. (0 to l0 inches thick)

Ckml--23 to 32 inches; pinkish white (7.5YR 8/2) and pink (7.5YR 8/4) indurated lime-cemented hardpan, light brown (7.5YR 6/4) and brown (7.5YR 5/4) moist; 85 percent pebbles, 2 percent cobbles and 3 percent stones; abrupt wavy boundary. (6 to l2 inches thick)

Ck2--32 to 39 inches; light brown (7.5YR 6/4) extremely gravelly sand, brown (7.5YR 4/4) moist; massive; hard and very hard, firm, nonsticky and nonplastic; common very fine and fine roots; common very fine interstitial pores; 75 percent pebbles; weakly cemented matrix with strongly lime-cemented masses and pebble clumps; slightly alkaline (pH 7.8); clear wavy boundary. (0 to l2 inches thick)

Ckm2--39 to 50 inches; light brown (7.5YR 6/4) strongly cemented and indurated lime hardpan, brown (7.5YR 4/4) moist; few fine roots in cracks; 60 percent pebbles, 5 percent cobbles; moderately alkaline (pH 7.9); clear wavy boundary. (0 to l4 inches thick)

Ck3--50 to 6l inches; light brown (7.5YR 6/4) extremely gravelly sand, brown (7.5YR 4/4) moist; massive; very hard, very firm, nonsticky and nonplastic; few fine roots; 65 percent pebbles, 3 percent cobbles; weakly lime cemented with areas of strong cementation; moderately alkaline (pH 7.9).

TYPE LOCATION: Clark County, Nevada; approximately ll25 feet north and 2450 feet east of the southwest corner of section l5, T. 22 S., R. 63 E.

RANGE IN CHARACTERISTICS:

Soil moisture: Moist in winter, dry in spring, summer and fall except for short periods following summer thunder showers.
Soil temperature: 67 to 70 degrees F.
Control section
Texture of fine earth: Averages loamy sand, loamy coarse sand or coarse sand.
Clay content: 2 to l2 percent.
Rock fragments: 35 to 85 percent, mainly pebbles.
Depth to lime hardpan: 20 to 40 inches.
Reaction: Mildly or moderately alkaline.

A horizon: Value=6 or 7 dry, 3, 4 or 5 moist.
Chroma:2 to 4.

C horizon: Hue=7.5YR or l0YR.
Value: 6 to 8 dry, 4 to 7 moist.
Chroma: 2 to 4.
Structure: Subangular blocky or is massive.

COMPETING SERIES: There are no other soils in the family. Other similar soils are Delnorte, Tencee and Winkel. These soils have loamy-skeletal control sections and have petrocalcic horizons at depths of less than 20 inches. Tencee soils have carbonatic mineralogy.

GEOGRAPHIC SETTING: Pittman soils are on erosional fan remnants and nonburied fan remnants at elevations of l200 to 2500 feet. Slopes range from 2 to 8 percent. These soils formed in alluvium from mostly basalt, rhyolite and limestone. The climate is warm and arid, with hot dry summers and mild dry winters. Mean annual precipitation is about 4 to 6 inches. Mean annual temperature is about 65 to 68 degrees F. The frost-free season is l80 to 270 days.

GEOGRAPHICALLY ASSOCIATED SOILS: These are the Arizo, Aztec, and Tonopah soils. These soils all lack petrocalcic horizons. Aztec soils have loamy-skeletal control sections and contain secondary gypsum.

DRAINAGE AND PERMEABILITY: Well drained; slow runoff; rapid permeability above the hardpan.

USE AND VEGETATION: Wildlife habitat and urban developement. Native vegetation is creosotebush, white bursage, occasional cholla, and catclaw along drainage channels.

DISTRIBUTION AND EXTENT: Portions of southern Nevada. The soils are of small extent.

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

SERIES ESTABLISHED: Clark County, Nevada, l964.

REMARKS: Type location relocated due to destruction of old site by urbanization.

Responsibility for this series was transferred from Davis to Phoenix 12/2015. The last revision to the series was 5/1997. ET

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National Cooperative Soil Survey
U.S.A.