LOCATION SEQUITE NV
Inactive Series
Rev. LJL/TM/RLB
02/2024
SEQUITE SERIES
The Sequite series consists of shallow to a hardpan, well drained soils that formed in lacustrine sediments. Sequite soils are on lake plain terraces and have slopes of 0 to 4 percent. The mean annual precipitation is about 6 inches and the mean annual air temperature is about 60 degrees F.
TAXONOMIC CLASS: Loamy-skeletal, carbonatic, thermic, shallow Calcic Petrocalcids
Calcic Petrocalcids
TYPICAL PEDON: Sequite extremely gravelly fine sandy loam, livestock grazing and wildlife habitat. (Colors are for dry soil unless otherwise noted.) The surface is partially covered by approximately 65 percent pebble-size pan fragments.
A--0 to 3 inches; very pale brown (10YR 7/3) extremely gravelly fine sandy loam, yellowish brown (10YR 5/4) moist; moderate medium and thick platy structure; slightly hard, very friable, slightly sticky and slightly plastic; few very fine roots; many very fine and few fine vesicular and interstitial pores; 65 percent pebble-size pan fragments; violently effervescent; moderately alkaline (pH 8.4); clear smooth boundary. (2 to 6 inches thick)
Bk--3 to 16 inches; pale brown (10YR 6/3) very gravelly sandy loam, yellowish brown (10YR 5/4) moist; weak medium subangular blocky structure; slightly hard, very friable, nonsticky and slightly plastic; many very fine, few fine and medium roots; common very fine and few fine interstitial pores; 40 percent pebble-size lime nodules; violently effervescent; very strongly alkaline (pH 9.2); clear wavy boundary. (8 to 16 inches thick)
Bkqm1--16 to 22 inches; white (10YR 8/1) very strongly cemented petrocalcic horizon, very pale brown (10YR 7/3) moist; moderate very thick platy structure; very rigid, rigid, very strongly cemented; common very fine and few fine and medium roots in fractures; common very fine and few fine tubular pores; violently effervescent; strongly alkaline (pH 8.8); clear wavy boundary. (2 to 6 inches thick)
Bkqm2--22 to 33 inches; white (10YR 8/1) continuously indurated petrocalcic horizon, pale brown (10YR 6/3) moist; massive; very rigid, indurated; few very fine and fine tubular pores; violently effervescent; strongly alkaline (pH 8.6); clear wavy boundary. (10 to 24 inches thick)
Bkq--33 to 60 inches; white (10YR 8/1) very gravelly loam, pale brown (10YR 6/3) moist; massive; moderately hard, friable, slightly sticky and slightly plastic; few very fine and fine tubular pores; 60 percent pebble-size lime nodules that are very rigid, rigid, strongly cemented; violently effervescent; strongly alkaline (pH 8.6).
TYPE LOCATION: Clark County, Nevada; approximately 0.6 miles east of Stump Spring in the southeast end of Pahrump Valley; about 150 feet south and 100 feet west of the northeast corner of section 5, T. 23 S., R. 55 E.; 35 degrees, 59 minutes, 01 seconds north latitude and 115 degrees, 48 minutes, 52 seconds west longitude.
RANGE IN CHARACTERISTICS:
Soil moisture - Usually dry, moist in some part for short periods during winter and early spring and for 10 to 20 days cumulative between July to October following convection storms. Has a typic-aridic moisture regime.
Soil temperature - 59 to 65 degrees F.
Depth to calcic horizon - 2 to 6 inches.
Depth to hardpan - 10 to 20 inches.
Calcium carbonate equivalent: 40 to 80 percent of the less than 20 mm fraction.
Control section - Percent clay: 8 to 16 percent.
Rock fragments: Averages 35 to 60 percent, composed mainly of lime nodules.
Bk horizon - Rock fragments: 35 to 60 percent, very rigid, rigid, very strongly cemented or indurated lime nodules.
Calcium carbonate equivalent: 25 to 40 percent of the less than 2 mm fraction. 40 to 80 percent of less than 20 mm fraction.
Secondary carbonates: Identifiable secondary carbonates as nodules, concretion or soft masses.
Bkqm horizons - Rupture resistance: Indurated or very strongly cemented .
Bkq horizon - Clay content: 10 to 18 percent.
Rock fragments: 35 to 60 percent, very rigid, rigid, very strongly cemented or indurated lime nodules.
Calcium carbonate equivalent: 40 to 60 percent of the less than 2 mm fraction.
COMPETING SERIES: There are no competing series.
Tencee (NM) soils are similar but lack a calcic horizon and rock fragments consisting of lime concretions.
GEOGRAPHIC SETTING: Sequite soils are on lake plain terraces. These soils formed in lacustrine sediments. Slopes are 0 to 4 percent. Elevations are 2700 to 3000 feet. The climate is hot and arid with warm, moist winters and hot, dry summers. The mean annual precipitation is 5 to 7 inches; mean annual air temperature is 57 to 63 degrees F., and the frost-free season is 180 to 240 days.
GEOGRAPHICALLY ASSOCIATED SOILS: These are the
Pahrump (NV) and
Vegastorm T(NV) series. Pahrump and Vegastorm soils both lack a petrocalcic horizon. Vegastorm soils have coarse-loamy control sections.
DRAINAGE AND PERMEABILITY: Well drained; slow runoff; moderately rapid permeability.
USE AND VEGETATION: Rangeland and wildlife habitat. The present vegetation is mainly shadscale, white bursage and creosotebush.
DISTRIBUTION AND EXTENT: Southern Nevada. MLRA 30. These soils are not extensive.
SOIL SURVEY REGIONAL OFFICE (SSRO) RESPONSIBLE: DAVIS, CALIFORNIA
SERIES PROPOSED: Clark County, Nevada, 1994. The name is coined from Mesquite Valley to the south.
REMARKS:
Diagnostic horizons and features recognized in this pedon are:
Ochric epipedon - The zone from the soil surface to a depth of 6 inches (A and upper part of Bk horizon).
Calcic horizon - More than 5 percent visible lime accumulation as nodules, concretion or soft masses
Petrocalcic horizon - The zone from 16 inches to 33 inches (Bkqm1 and Bkqm2 horizons).
Particle-size control section - The zone from 10 inches to 16 inches (Part of the Bk horizon).
Calcic feature - The lime concretions that are considered rock fragments make up more than the 5 percent requirement of visible lime accumulation.
National Cooperative Soil Survey
U.S.A.