LOCATION SWEETSPRING             NV

Established Series
Rev. DJM/ET
12/2015

SWEETSPRING SERIES

The Sweetspring series consists of very deep, well drained soils that formed in mixed alluvium. Sweetspring soils are on fan remnants. Slope ranges from 2 to 8 percent. The mean annual precipitation is about 4 inches and the mean annual temperature is about 73 degrees F.

TAXONOMIC CLASS: Sandy-skeletal, mixed, hyperthermic Petronodic Calciargids

TYPICAL PEDON: Sweetspring extremely gravelly loam, rangeland and wildlife habitat. (Colors are for dry soil unless otherwise noted.) The soil surface is covered by approximately 85 percent pebbles.

A--0 to 1 inch; light yellowish brown (10YR 6/4) extremely gravelly loam, dark yellowish brown (10YR 4/4) moist; strong thick platy structure; slightly hard, very friable, slightly sticky and moderately plastic; common fine roots; many fine and fine vesicular pores; 70 percent pebbles and 5 percent cobbles; violently effervescent; moderately alkaline (pH 8.4); abrupt smooth boundary. (1 to 3 inches thick)

Bt--1 to 4 inches; reddish yellow (7.5YR 6/6) extremely gravelly loam, brown (7.5YR 4/4) moist; moderate very coarse prismatic parting to common moderate subangular blocky structure; slightly hard, very friable, slightly sticky and moderately plastic; common very fine and few fine roots; many very fine interstitial and common very fine tubular pores; common, distinct, thin continuous clay films on all faces of peds and lining pores; 50 percent pebbles and 10 percent cobbles; violently effervescent; moderately alkaline (pH 8.4); abrupt wavy boundary. (3 to 6 inches thick)

Bkq1--4 to 7 inches; light reddish yellow (7.5YR 6/6) extremely gravelly sandy loam, brown (7.5YR 4/4) moist; massive; soft, very friable, nonsticky and nonplastic; common very fine and few fine roots; common very fine and fine interstitial pores; 15 percent fine calcium carbonate coats on bottoms and sides of rock fragments; few (1 percent) distinct silica coats on the undersides of rock fragments; 60 percent pebbles and 5 percent cobbles; violently effervescent; moderately alkaline (pH 8.4); abrupt wavy boundary.

Bkq2--7 to 17 inches; light brown (7.5YR 6/4) extremely gravelly sandy loam, brown (7.5YR 5/4) moist; massive; soft, very friable, nonsticky and nonplastic; few very fine roots; few very fine tubular pores; 55 percent fine calcium carbonate coats on the bottom of rock fragments; few (2 percent) distinct silica coats on the bottom of rock fragments; 65 percent pebbles and 10 percent cobbles; violently effervescent; moderately alkaline (pH 8.4); clear wavy boundary. (Combined thickness of the Bkq horizons is 8 to 17 inches.)

2Bkq3--17 to 22 inches; light yellowish brown (10YR 6/4) stratified extremely gravelly coarse sand and very gravelly loamy sand, dark yellowish brown (10YR 4/4) moist; massive; moderately hard, firm, nonsticky and nonplastic; few very fine roots; common very fine interstitial and few fine and medium tubular pores; 80 percent medium calcium carbonate coats on the bottom of rock fragments; 25 percent soft masses and filaments; few (3 percent) fine (1 to 2 millimeter) silica coats on the bottom of rock fragments; many (35 percent) medium (2 to 5 millimeter) weakly cemented calcium carbonate lenses; 80 percent pebbles and 5 percent cobbles; violently effervescent; moderately alkaline (pH 8.4); abrupt wavy boundary (5 to 10 inches thick)

2Bkq4--22 to 62 inches; pale brown (10YR 6/3) stratified extremely gravelly sand and extremely gravelly loamy sand, brown (10YR 4/3) moist; massive; moderately hard, firm, nonsticky and nonplastic; few very fine roots; common very fine interstitial and few fine and medium tubular pores; 80 percent medium calcium carbonate coats on the bottom of rock fragments; common (25 percent) soft masses and filaments; few (3 percent) fine (1 to 2 millimeter) silica coats on the bottom of rock fragments; many (35 percent) medium (2 to 5 millimeter) weakly cemented calcium carbonate lenses; 80 percent pebbles and 5 percent cobbles; violently effervescent; strongly alkaline (pH 8.6); abrupt wavy boundary

TYPE LOCATION: Clark County, Nevada; south of the road that turns west off the Gold Butte Scenic Byway for river access, about 2 miles south of Juanita Springs Ranch; about 1,245 feet south and 178 feet west of the northeast corner of section 20, T. 14 S., R. 69 E. on the Overton S.E., NV 7.5 minute topographic quadrangle; 36 degrees 37 minutes 10 seconds north latitude and 114 degrees 17 minutes 37 seconds west longitude; UTM 11, 742018e, 4056089n, NAD83.

RANGE IN CHARACTERISTICS:
Soil moisture - Usually dry, moist in some part during winter and spring and intermittingly moist in the upper part following summer convection storms; tyic aridic soil moisture regime.

Mean annual soil temperature - 72 to 78 degrees F.
Depth to base of argillic horizon - 4 to 7 inches.
Depth to calcic horizon 4 to 7 inches.
Reaction: Moderately alkaline or strongly alkaline.

Control section - Clay content: Averages 8 to 15 percent.
Rock fragments: 50 to 85 percent.

A horizon - Hue: 7.5YR or 10YR.
Value: 6 or 7 dry, 4 or 5 moist.
Chroma: 2 through 4.


Bt horizon - Hue: 5YR, 10YR or 7.5YR.
Value: 5 or 6 dry, 4 or 5 moist.
Chroma: 4 through 6.
Texture: Sandy clay loam, loam or very fine sandy loam.
Clay content: 15 to 27 percent.
Rock fragments: 50 to 70 percent pebbles.
Calcium carbonate equivalent: 5 to 10 percent.

Bkq horizons - Hue: 5YR or 7.5YR.
Value: 5 or 6 dry, 4 or 5 moist.
Chroma: 4 through 6.
Texture: Fine sandy loam or sandy loam.
Clay content: 5 to 12 percent.
Rock fragments: 35 to 80 percent pebbles and minor amounts of cobbles.
Calcium carbonate equivalent: 10 to 25 percent.

2Bkq horizons Hue: 5YR, 7.5YR or 10YR.
Value: 5, 6 or 7 dry, 4 or 5 moist.
Texture of fine earth: Stratified loamy fine sand through coarse sand.
Clay content: 2 to 10
Rock fragments: 60 to 85 percent mainly pebbles.
Consistence: Hard or very hard.
Calcium carbonate equivalent: 10 to 25 percent.
Other features: 20 to 50 percent of the horizons have weakly to moderately calcium carbonate cemented lenses of with minor amounts of silica. Some pedons contain very few, fine gypsum segregations.

COMPETING SERIES: There are no competing series.

GEOGRAPHIC SETTING: Sweetspring soils are on fan remnants. These soils formed in alluvium from mixed rock sources. Slope ranges from 2 to 8 percent. Elevations are 1,300 to 2,400 feet. The climate is low-latitude desert, with mild winters and very hot summers. Precipitation is greatest in the winter with a lesser secondary peak in the summer, typical of the Mojave Desert. The mean annual precipitation is 3 to 5 inches; mean annual temperature is 69 to 76 degrees F.; and the frost-free season is 280 to 320 days.

GEOGRAPHICALLY ASSOCIATED SOILS: These are the Carrizo and Huevi soils. Carrizo soils lack an argillic or calcic horizon. Huevi soils have a duric feature at 18 to 60 inches.

DRAINAGE AND PERMEABILITY: Well drained; slow runoff; moderate permeability.

USE AND VEGETATION: The native vegetation consists of creosotebush, white bursage, cacti and plantain.

DISTRIBUTION AND EXTENT: Mojave Desert of southern Nevada; MLRA 30. These soils are not extensive.

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

SERIES ESTABLISHED: Clark County Area, Nevada, 2006. Proposed in Clark County (Virgin River Area), Nevada, 2004.

REMARKS: The Sweetspring series was mapped as the Bitter Spring series in the original Virgin River soil survey. Sweetspring is classified as having a hyperthermic temperature regime and a sandy-skeletal particle size control section to better represent the series concept at lower elevations.

Diagnostic horizon and features recognized in this pedon are:

Ochric epipedon - 0 to 1 inches (A horizon).
Argillic horizon - 1 to 4 inches (Bt horizon).
Calcic horizon - 4 to 62 inches (Bkq1, Bkq2, 2Bkq3 and 2Bkq4 horizons).
Petronodic feature 17 to 62 inches (2Bkq3 and 2Bkq4 horizons).
Particle-size control section - 1 to 40 inches (Bt, Bkq1, Bkq2, 2Bkq3 and part of the 2Bkq4 horizons).

Responsibility for this series was transferred from Davis to Phoenix 12/2015. The last revision to the series was 7/2006. ET

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National Cooperative Soil Survey
U.S.A.