LOCATION PIEDRABLANCA            NM

Established Series
Rev GWC-DAW
03/2016

PIEDRABLANCA SERIES

The Piedrablanca series consists of very deep, moderately well drained soils that formed in gypsiferous eolian deposits over gypsiferous lacustrine deposits. These nearly level soils are on interdune areas overlying playa steps, and stabilized, vegetated playa steps. Slopes range from 0 to 3 percent. The mean annual precipitation is about 8 inches and the mean annual air temperature is about 67 degrees F.

TAXONOMIC CLASS: Gypseous-skeletal, hypergypsic, thermic Leptic Haplogypsids

TYPICAL PEDON: Piedrablanca gypsiferous loam - rangeland. (Colors are for dry soil unless otherwise noted)

Ay--0 to 2 inches; very pale brown (10YR 7/3) gypsiferous loam, pale brown (10YR 6/3), moist; 23 percent clay; moderate medium platy structure; soft, very friable, moderately sticky, slightly plastic; few very fine roots throughout; many very fine vesicular pores; carbonate, finely disseminated throughout and gypsum, finely disseminated throughout; strongly effervescent, 8 percent calcium carbonate equivalent and 26 percent gypsum; slightly alkaline, pH 7.6; electrical conductivity 4.4 dS/m; slightly saline; clear smooth boundary.

Byy--2 to 22 inches; light gray (10YR 7/2) gypsiferous loamy sand, light brownish gray (10YR 6/2), moist; 5 percent clay; weak fine subangular blocky structure; soft, very friable, slightly sticky, nonplastic; few very fine roots throughout; many very fine irregular and many fine interstitial pores; carbonate, finely disseminated throughout and gypsum, finely disseminated throughout and many coarse irregular gypsum masses throughout; slightly effervescent, 6 percent calcium carbonate equivalent and 72 percent gypsum; slightly alkaline, pH 7.5; electrical conductivity 4.8 dS/m; slightly saline; clear smooth boundary.

2BCyy--22 to 30 inches; light gray (10YR 7/2) gypsiferous extremely channery loamy sand, light brownish gray (10YR 6/2), moist; 10 percent clay; weak fine subangular blocky structure; soft, very friable, slightly sticky, nonplastic; many very fine irregular and many fine interstitial pores; salt, finely disseminated throughout and carbonate, finely disseminated throughout and gypsum, finely disseminated throughout and common fine irregular gypsum masses throughout; 65 percent, flat, angular, very strongly cemented, 2 to 150 millimeter, gypsum crystal fragments; slightly effervescent, 2 percent calcium carbonate equivalent and 75 percent gypsum; neutral, pH 7.2; electrical conductivity 5.8 dS/m; slightly saline; gradual smooth boundary.

2Cyyz--30 to 37 inches; light brownish gray (10YR 6/2) gypsiferous extremely channery loamy sand, grayish brown (10YR 5/2), moist; 8 percent clay; massive; loose, loose, slightly sticky, nonplastic; many very fine irregular and many fine interstitial pores; carbonate, finely disseminated throughout and gypsum, finely disseminated throughout and salt, finely disseminated throughout; 70 percent, flat, angular, very strongly cemented, 2 to 150 millimeter, gypsum crystal fragments; very slightly effervescent, 2 percent calcium carbonate equivalent and 80 percent gypsum; neutral, pH 7.3; electrical conductivity 8.0 dS/m; moderately saline; gradual smooth boundary.

2Cyyzg--37 to 60 inches; gray (N 5) gypsiferous channery sand, grayish brown (10YR 5/2), moist; 2 percent clay; massive; loose, loose, nonsticky, nonplastic; many very fine interstitial pores; gypsum, finely disseminated throughout and common fine irregular gypsum crystals, unspecified throughout; 16 percent, flat, angular, very strongly cemented, 2 to 150 millimeter, gypsum crystal fragments; noneffervescent, 0 percent calcium carbonate equivalent and 76 percent gypsum; neutral, pH 7.2; electrical conductivity 18.0 dS/m; strongly saline.

TYPE LOCATION: Dona Ana County, New Mexico. USGS Quad Heart of the Sands SW; approximately 13.5 miles west of the intersection of US Highway 70 and the White Sands National Monument entrance; 1,636 feet north and 136 feet east of the southwest corner of Section 2, Township 18 S, Range 5 E. Latitude: 32 degrees 46 minutes 14.4 seconds north, Longitude: 106 degrees 24 minutes 37.70 seconds west, NAD 83; UTM Easting: 367895 meters, UTM Northing: 3626744 meters. UTM zone 13.

RANGE IN CHARACTERISTICS:
Soil moisture: Typic aridic soil moisture regime. The moisture control section is usually dry in all parts more than three-fourths of the time that the soil temperature exceeds 41 degrees F. at 20 inches. This soil has transitory internal free water and a fluctuating water table below the particle-size control section. Water table is at 43 to 60 inches in most years.

Mean annual soil temperature: 66 to 72 degrees F.

Particle-size control section (weighted average)
Clay content: 1 to 27 percent
Rock fragments: 15 to 80 percent, averages greater than 35 percent
Percent gypsum: 40 to 90 percent

Ay and Ayy horizons
Hue: 10YR, 2.5Y
Value: 6 to 9 dry, 4 to 8 moist
Chroma: 1 to 4, dry or moist
Texture: gypsiferous coarse sand, gypsiferous sand, gypsiferous loamy coarse sand, sandy loam, gypsiferous sandy loam, loam, gypsiferous loam, gypsiferous clay loam, gypsiferous loamy sand
Clay: 1 to 28 percent
Gypsum: 15 to 90 percent
Reaction: neutral to slightly alkaline
Salinity: very slightly saline to slightly saline

Byy and 2BCyy horizons
Hue: 10YR, 2.5Y
Value: 6 to 9 dry, 4 to 8 moist
Chroma: 1 to 4, dry or moist
Texture: gypsiferous sand, gypsiferous coarse sand, gypsiferous loamy sand, gypsiferous sandy loam, gypsiferous loam, gypsiferous sandy clay loam
Clay: 1 to 27 percent
Rock fragments: 0 to 75 percent, averages greater than 35 percent
Calcium carbonate equivalent: 0 to 6 percent
Gypsum: 40 to 100 percent
Reaction: neutral to moderately alkaline
Salinity: very slightly saline to slightly saline

Cyy, 2Cyyz and 2Cyyzg horizons
Hue: 10YR, 2.5Y, N
Value: 5 to 9.5 dry, 5 to 9 moist
Chroma: 1 to 4, dry or moist
Texture: gypsiferous sand, gypsiferous loamy coarse sand, gypsiferous loamy sand, gypsiferous sandy loam, gypsiferous coarse sand
Clay: 1 to 12 percent
Rock fragments: 10 to 75 percent
Calcium carbonate equivalent: 0 to 2 percent
Gypsum: 40 to 100 percent
Reaction: neutral to slightly alkaline
Salinity: moderately saline to strongly saline

COMPETING SERIES: There are no competing series.

GEOGRAPHIC SETTING: Piedrablanca soils are on interdune areas overlying playa steps, and stabilized, vegetated playa steps. Slope is 0 to 3 percent. These soils formed in gypsiferous eolian deposits over gypsiferous lacustrine deposits. Elevation ranges from 3,890 to 4,050 feet. The mean annual precipitation is 8 to 12 inches. Precipitation falls mostly during the months of July through September. The mean annual air temperature is 64 to 70 degrees F. The frost-free period is 180 to 240 days.

GEOGRAPHICALLY ASSOCIATED SOILS: These are the Carreta (NM), Lark (NM), Nasa (NM), Ratscat (NM), Salago (NM) and Wulie (NM) soils. Carreta soils are on playas and are gypseous-skeletal. Nasa soils are on playa steps and have a moderately deep petrogypsic horizon. Ratscat soils have a shallow petrogypsic horizon. Salago soils are on playas and are coarse gypseous. Wulie soils are on playa steps and are coarse-gypseous.

DRAINAGE AND PERMEABILITY: Moderately well to well drained; negligible to low runoff; moderately rapid to very rapid permeability. Water table ranges from 43 to 60 inches during most years.

USE AND VEGETATION: The major uses are wildlife habitat, recreation and research activities. Native vegetation is alkali sacaton, Torrey ephedra, fourwing saltbush, hairy coldenia.

DISTRIBUTION AND EXTENT: South central New Mexico, limited to White Sands National Monument. MLRA 42, Piedrablanca is of limited extent.

MLRA SOIL SURVEY REGIONAL OFFICE (MO) RESPONSIBLE: Phoenix, Arizona

SERIES ESTABLISHED: White Sands National Monument, Dona Ana County, New Mexico, 2015. The name Piedrablanca translates to white stone in English.

REMARKS: Diagnostic horizon and features recognized in this pedon are:

Particle-size control section - the zone from 10 to 40 inches (Byy, 2BCyy, 2Cyyz and 2Cyyzg horizons)

Ochric epipedon - the zone from 0 to 2 inches (Ay horizon)

Gypsic horizon - the zone from 2 to 60 inches (Byy, 2BCyy, 2Cyyz, and 2Cyyzg horizons)

Soils classified according to Soil Taxonomy Second Edition, 1999; Keys to Soil Taxonomy, Twelfth Edition, 2014

Revised for the correlation of White Sands National Monument, New Mexico; April, 2015, NMS

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National Cooperative Soil Survey
U.S.A.