LOCATION MCCULLOUGH NV+NM
Established Series
Rev. ELS/RLB/ET
11/2015
MCCULLOUGH SERIES
The McCullough series consists of very deep, well drained soils that formed in alluvium from mixed rock sources. The McCullough soils are on inset fans, fan skirts and alluvial flats. Slopes are 0 to 8 percent. The mean annual precipitation is about 5 inches and the mean annual temperature is about 65 degrees F.
TAXONOMIC CLASS: Coarse-loamy, mixed, superactive, calcareous, thermic Typic Torriorthents
TYPICAL PEDON: McCullough fine sandy loam-desert wildlife habitat. (Colors are for dry soil unless otherwise noted.
A--0 to 2 inches; pink (7.5YR 7/4) fine sandy loam, brown (7.5YR 5/4)moist; moderate fine and medium platy structure; soft, very friable, nonsticky and nonplastic; few very fine roots; few very fine vesicular and many very fine interstitial pores; violently effervescent; moderately alkaline (pH 8.4); 5 percent pebbles; abrupt wavy boundary. (1 to 3 inches thick)
Bw--2 to 5 inches; light brown (7.5YR 6/4) gravelly sandy loam, strong brown (7.5YR 5/6) moist; very weak coarse prismatic structure; slightly hard, very friable, nonsticky and nonplastic; common very fine roots; common very fine tubular and many very fine interstitial pores; 15 percent pebbles; common faint clay films on undersides of pebbles; violently effervescent; moderately alkaline (pH 8.4); abrupt wavy boundary. (0 to 10 inches thick)
C1--5 to 20 inches; pink (7.5YR 7/4) fine sandy loam, strong brown (7.5YR 5/6) moist; many coarse distinct iron mottles, reddish yellow (7.5YR 6/8) moist; few coarse faint soft lime masses, pink (7.5YR 7/4) moist; weak fine subangular blocky structure; soft, very friable, nonsticky and slightly plastic; few medium and common very fine and fine roots; few fine and medium and many very fine interstitial pores; violently effervescent; moderately alkaline (pH 8.4); clear wavy boundary. (10 to 20 inches thick)
C2--20 to 26 inches; pink (7.5YR 8/4) fine sandy loam, light brown (7.5YR 6/4) moist; few fine distinct iron mottles, reddish yellow (7.5YR 6/8), and pink (7.5YR 7/4) moist; massive; soft, very friable, nonsticky and slightly plastic; common very fine and fine roots; few very fine tubular and many very fine interstitial pores; violently effervescent; moderately alkaline (pH 8.4); abrupt wavy boundary. (0 to 12 inches thick)
Cky1--26 to 32 inches; pink (7.5YR 7/4) loam, brown (7.5YR 5/4) moist; common medium distinct iron mottles, strong brown (7.5YR 5/6) moist; very weak fine subangular blocky structure; slightly hard, very friable, slightly sticky and slightly plastic; many fine and very fine roots; many very fine interstitial and tubular pores; common fine lime and gypsum filaments, weak lime cementation, violently effervescent; moderately alkaline (pH 8.4); abrupt wavy boundary. (0 to 12 inches thick)
Cky2--32 to 35 inches; pink (7.5YR 7/4) fine sandy loam, brown (7.5YR 5/4) moist; common medium distinct iron mottles, strong brown (7.5YR 5/6) moist; moderate medium subangular blocky structure; hard, friable, slightly sticky and slightly plastic; common fine roots; common very fine tubular pores; weak lime and gypsum cementation; violently effervescent, strongly alkaline (pH 8.6); abrupt wavy boundary. (0 to 12 inches thick)
2C'1--35 to 48 inches; pink (7.5YR 7/4) fine sand, strong brown (7.5YR 5/6) moist; massive; soft, very friable, nonsticky and nonplastic; few fine roots; many very fine interstitial pores; violently effervescent; strongly alkaline (pH 8.6); abrupt wavy boundary. (10 to 20 inches thick)
2C'2--48 to 62 inches; pink (7.5YR 7/4) fine sand, brown (7.5YR 5/4) moist; massive; soft, very friable, nonsticky and nonplastic; common fine roots; many very fine interstitial pores; strongly effervescent; strongly alkaline (pH 8.6).
TYPE LOCATION: Clark County, Nevada; about 600 feet east and 1,120 feet north of the southwest corner of section 5, T. 22 S., R. 61 E.
RANGE IN CHARACTERISTICS:
Soil moisture: Usually dry. Moist for short periods throughout the moisture control section December through March. Moist above and periodically in upper part of moisture control section for 10 to 20 days cumulative June through September.
Soil temperature: 64 to 70 degrees F.
Reaction: - Moderately alkaline or strongly alkaline.
Control section - Percent clay: 8 to 18 percent in upper part, 2 to 8 percent in lower part.
Rock fragments: Less than 15 percent, by average.
A horizon - Hue: 5YR, 7.5YR, 10YR.
Value: 4 through 7 dry, 3 through 5 moist.
Chroma: 3 or 4.
C horizon - Hue: 5YR, 7.5YR or 10YR.
Value: 4 through 8 dry, 3 through 5 moist.
Chroma: 3 through 6.
Texture: Stratified, averaging sandy loam, fine sandy loam, or loam with more than 50 percent fine sand or coarser in the upper part, and coarse sand through loamy fine sand in the lower part.
Lime and gypsum: Commonly has soft lime masses and filaments, gypsum crystals, and pendants of lime and gypsum in lower C horizons.
Other features: Some pedons have contrasting substrata below 40 inches.
COMPETING SERIES: These are the
Bitterwater,
Corbilt (T),
Elkhills,
Kimberlina, and
Seaman series. Bitterwater, Elkhills and Kimberlina soils lack the 10 to 20 days of summer precipitation during summer convection storms. Bitterwater soils also have a paralithic contact between 50 to 60 inches and lack significant sandy strata in the lower part of the control section. Corbilt soils contain 15 to 20 percent CaC03 in the control section, and depth to carbonates range from 5 to 20 inches deep, and also contain a Bq horizon that is weakly silica cemented. Seaman soils have a component of volcanic ash and lack significant sand strata in the lower part of the control section.
GEOGRAPHIC SETTING: McCullough soils are on inset fans, fan skirts, and alluvial flats. These soils formed in alluvium from mixed rock sources commonly with a component of gypsiferous materials. Slopes are 0 to 8 percent. Elevations are 1,900 to 4,800 feet. The climate is arid with hot dry summers and mild winters. The mean annual precipitation is 4 to 10 inches; mean annual temperature is 62 to 68 degrees F., and the frost-free season is 170 to 250 days.
GEOGRAPHICALLY ASSOCIATED SOILS: These are the
Alamogordo,
Goodsprings,
Holloman,
Jean,
Largo and
Prelo soils. Alamogordo soils have gypsic horizons. Jean soils have sandy-skeletal control sections. Goodsprings soils have petrocalcic horizons. Holloman soils are shallow over bedded gypsum. Largo and Prelo soils have fine-silty control sections.
DRAINAGE AND PERMEABILITY: Well drained, slow or medium runoff; moderate permeability.
USE AND VEGETATION: Rangeland and wildlife habitat. The present vegetation is mainly creosotebush, white bursage, big galleta, and Indian ricegrass.
DISTRIBUTION AND EXTENT: Southern Nevada in MLRA 30 and southern New Mexico. These soils are not extensive.
MLRA SOIL SURVEY REGIONAL OFFICE (MO) RESPONSIBLE: PHOENIX, ARIZONA
SERIES ESTABLISHED: Clark County (Las Vegas and El Dorado Valleys Area), Nevada. 1964.
REMARKS: The type location was moved to better represent the present concept of the series. The activity class was added to the classification in March of 2003. Competing series were not checked at that time. - ET
Responsibility for this series was transferred from Davis to Phoenix 11/2015. - ET
Diagnostic horizon and features recognized in this pedon are:
Ochric epipedon - The zone from the surface to 2 inches
Particle- size control section - The zone from 10 to 40 inches ( part of the C2, C3, Cky1, Cky2 and part of the 2C1 horizon)
National Cooperative Soil Survey
U.S.A.