LOCATION LUAP NV

Established Series
Rev. STD-DWW-RLB-JBF
12/2011

LUAP SERIES

The Luap series consists of moderately deep to a strongly cemented lime hardpan, well drained soils that formed in alluvium derived from mixed rocks with a component of loess and volcanic ash. The Luap soils are on fan skirts and offshore bars. Slopes are 2 to 8 percent. The mean annual precipitation is about 180 mm and the mean annual temperature is about 8 degrees C.

TAXONOMIC CLASS: Loamy-skeletal, mixed, superactive, mesic Typic Petrocalcids

TYPICAL PEDON: Luap very gravelly fine sandy loam--rangeland. The soil surface is partially covered with 45 percent gravel. (Colors are for dry soil unless otherwise noted.)

A--0 to 8 cm; light gray (10YR 7/2) very gravelly fine sandy loam, brown (10YR 5/3) moist; massive; slightly hard, very friable, nonsticky and nonplastic; common very fine roots; many very fine and few fine interstitial pores; 40 percent gravel; violently effervescent; strongly alkaline (pH 8.8); clear wavy boundary. (5 to 10 cm thick)

Bw--8 to 20 cm; light gray (10YR 7/2) very gravelly very fine sandy loam, brown (10YR 5/3) moist; weak fine subangular blocky structure; slightly hard, very friable, nonsticky and nonplastic; common very fine and few fine and medium roots; many very fine and few fine interstitial pores; 35 percent gravel; violently effervescent; strongly alkaline (pH 9.0); abrupt wavy boundary. (10 to 25 cm thick)

Bk1--20 to 58 cm; very pale brown (10YR 8/4) very gravelly very fine sandy loam, light yellowish brown (10YR 6/4) moist; massive; hard, firm, nonsticky and nonplastic; common very fine roots; many very fine and few fine interstitial pores; 50 percent discontinuous weak lime cementation; 40 percent gravel; few, fine soft lime masses; violently effervescent; strongly alkaline (pH 8.8); abrupt wavy boundary. (23 to 50 cm thick)

2Bk2--58 to 94 cm; variegated extremely gravelly coarse sand; single grained; loose, nonsticky and nonplastic; common very fine roots; many very fine interstitial pores; 70 percent gravel; thin lime coats on undersides of gravel; violently effervescent; moderately alkaline (pH 8.2); abrupt wavy boundary. (0 to 40 thick)

3Bkm--94 to 112; very pale brown (10YR 8/2) continuous strongly cemented lime hardpan, pale yellow (2.5Y 7/4) moist; massive; extremely hard, extremely firm; 70 percent gravel; violently effervescent; clear wavy boundary. (5 to 20 thick)

4Ck--112 to 155 cm; variegated extremely gravelly coarse sand; massive; hard, firm, nonsticky and nonplastic; many very fine interstitial pores; 50 percent discontinuous weak lime cementation; 80 percent gravel; violently effervescent; moderately alkaline (pH 8.2).

TYPE LOCATION: Elko County, Nevada; approximately 2 miles southeast of Montello, about 250 feet east and 2,400 feet south of the northwest corner, sec. 22, T. 39 N., R. 69 E.; latitude 41 degrees 15 minutes 23 seconds N and longitude 114 degrees 09 minutes 40 seconds W; NAD 83.

RANGE IN CHARACTERISTICS:
Soil moisture: Usually dry, moist for short periods in the winter and spring, dry late May through early November; typic aridic soil moisture regime.
Mean annual soil temperature: 12 to 15 degrees C.
Depth to petrocalcic horizon: 50 to 100 cm.
Reaction: Moderately alkaline or strongly alkaline.
Sodium absorption ratio: Ranges from 6 to 25 between a depth of 25 cm to the petrocalcic horizon.

Particle-size ontrol section - Clay content: 8 to 18 percent.
Rock fragments: Averages 45 to 70 percent gravel.

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

Bw horizons
Value: 6 or 7 dry, 4 or 5 moist.
Chroma: 2 through 4.
Texture: Very gravelly very fine sandy loam or very gravelly loam.

Bk horizons
Value: 7 or 8 dry, 6 or 7 moist.
Chroma: 2 through 4.
Texture: Very gravelly very fine sandy loam, fine sandy loam or loam with extremely gravelly coarse sand or loamy sand common in some lower subhorizons.

COMPETING SERIES: There are no other series in the family.

GEOGRAPHIC SETTING: Luap soils are on fan skirts and offshore bars. These soils formed in alluvium derived from mixed rocks with a component of loess and volcanic ash. Slopes are 2 to 8 percent. Elevations are 1,465 to 1,800 meters. The climate is cool, semiarid with warm, dry summers and cool, moist winters. The mean annual precipitation is 150 to 200 mm; mean annual temperature is 7 to 10 degrees C; and the frost-free season is 100 to 130 days.

GEOGRAPHICALLY ASSOCIATED SOILS: These are the Clowfin, Piltdown and Valmy series. Clowfin and Piltdown soils lack lime cementation. In addition Piltdown soils have less than 15 percent rock fragments in the particle-size control section. Valmy soils lack a petrocalcic horizon and have less than 35 percent rock fragments in the particle-size control section.

DRAINAGE AND SATURATED HYDRAULIC CONDUCTIVITY: Well drained; medium runoff; moderate high saturated hydraulic conductivity.

USE AND VEGETATION: Rangeland and wildlife habitat. The present vegetation is mainly shadscale, bud sagebrush, Indian ricegrass, black greasewood and bottlebrush squirreltail.

DISTRIBUTION AND EXTENT: Northeastern Nevada. These soils are not extensive.

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

SERIES ESTABLISHED: Elko County, Nevada, northeast part, 1986.

REMARKS: Diagnostic horizons and features recognized in this pedon are:
Ochric epipedon - The zone from the soil surface to 18 cm (A and part of the Bw horizons).
Petrocalcic horizon - The zone from about 94 to 112 cm (3Bkm horizon).
Particle-size control section - The zone from about 25 to 94 cm (Bk1, 2Bk2 horizons and part of the Bw horizon).

National Cooperative Soil Survey
U.S.A.