LOCATION GRASSVAL NV+OR
Established Series
Rev. CEJ/RLB/JBF
03/2016
GRASSVAL SERIES
The Grassval series consists of shallow and very shallow over indurated duripan, well drained soils that formed in alluvium derived from mixed rocks. Grassval soils occur on fan piedmont remnants. Slopes are 2 to l5 percent. The mean annual precipitation is about 230 mm and the mean annual temperature is about 8 degrees C.
TAXONOMIC CLASS: Loamy, mixed, superactive, mesic, shallow Xeric Argidurids
TYPICAL PEDON: Grassval fine sandy loam--rangeland. (Colors are for dry soils unless otherwise noted.) The surface is covered with approximately 10 percent gravel.
A--0 to 10 cm; light brownish gray (10YR 6/2) fine sandy loam, brown (10YR 4/3) moist; weak thin platy structure; slightly hard, very friable, nonsticky and slightly plastic; few fine and very fine roots; few medium and many fine vesicular pores; 10 percent gravel; slightly effervescent; moderately alkaline (pH 8.0); abrupt smooth boundary. (5 to 13 cm thick)
Bt--10 to 25 cm; pale brown (10YR 6/3) gravelly loam, dark yellowish brown (10YR 4/4) moist; moderate medium subangular blocky structure; slightly hard, friable, moderately sticky and moderately plastic; few medium and coarse and common fine roots; common fine and very fine tubular pores; common faint clay films on peds; 20 percent gravel and 5 percent cobbles; violently effervescent; moderately alkaline (pH 8.2); clear wavy boundary. (10 to 18 cm thick)
Btk--25 to 33 cm; light yellowish brown (10YR 6/4) gravelly clay loam, yellowish brown (10YR 5/4) moist; moderate medium and coarse subangular blocky structure; hard, friable, moderately sticky and moderately plastic; common fine roots; common fine tubular pores; common faint clay films on ped faces; 20 percent gravel and 5 percent cobbles; carbonate coats on undersides of gravel and many fine and medium soft masses; violently effervescent; strongly alkaline (pH 8.8); abrupt smooth boundary. (5 to 13 cm thick)
Bqkm--33 to 152 cm; white (10YR 8/1) indurated duripan with thin horizontal lenses that are weakly or strongly cemented; violently effervescent.
TYPE LOCATION: Lander County, Nevada; approximately 10 miles east of Austin in the northern part of Smoky Valley, about 1,950 feet north and 1,900 feet west of the southeast corner of section 25, T. 19 N., R. 45 E.; USGS Cape Horn 7.5 minute topographic quadrangle; latitude 39 degrees 28 minutes 38 seconds N and longitude 116 degrees 51 minutes 49 seconds W; WGS84 Decimal Degrees 39.4772222 latitude, -116.8636111longitude.
RANGE IN CHARACTERISTICS:
Soil moisture: Usually dry, moist in winter and spring, dry early June through October; aridic soil moisture regime bordering on xeric.
Mean annual soil temperature: 8 to 10 degrees C.
Depth to duripan: 20 to 36 cm.
Depth to carbonates: Calcareous throughout, effervescence increasing with depth; segregated carbonate common in lower portion of the solum.
Particle-size control section - Percent clay: 18 to 27 percent.
Rock fragments: 15 to 35 percent, mainly gravel.
A horizon
Value: 3 or 4 moist.
Chroma: 2 or 3.
Reaction: Slightly alkaline or moderately alkaline.
Bt and Btk horizons
Value: 5 or 6 dry, 4 or 5 moist.
Chroma: 3 or 4.
Texture: Gravelly loam or gravelly clay loam.
Clay content: 25 to 35 percent.
Structure: Prismatic or subangular blocky structure.
Consistence: Slightly hard or hard, slightly sticky or sticky and slightly plastic or plastic.
Reaction: Moderately alkaline or strongly alkaline.
COMPETING SERIES: These are the
Argalt,
Bigfrog,
Bruncan,
Chuckridge,
Chuska,
Colthorp,
Dewar,
Handpah,
Minu,
Packwood,
Pipeline,
Roseworth,
Roval,
Thoms, and
Wellington series.
Argalt,
Bruncan,
Colthorp and
Packwood soils have bedrock within 100 cm.
Bigfrog soils are noncalcareous above the duripan.
Chuckridge,
Handpah,
Minu and
Roval soils have summer moisture.
Chuska soils have a noncalcareous upper argillic and a 10 to 30 cm thick indurated duripan.
Dewar soils have 27 to 35 percent clay in the particle-size control section and are 36 to 50 cm deep to a duripan.
Pipeline soils have less than 15 percent coarse fragments in the particle-size control section and are noncalcareous in the upper argillic.
Roseworth soils have A horizons that are neutral.
Thoms soils lack secondary carbonate in the argillic and are neutral to slightly acid.
Wellington soils have noncalcareous and neutral or slightly acid.
GEOGRAPHIC SETTING: Grassval soils are on fan piedmont remnants. These soils formed in alluvium derived from mixed rocks. Elevations are 1,620 to 2,260 meters. Slopes are 2 to 15 percent. The climate is cool, semiarid with warm, dry summers and cool, moist winters. The mean annual precipitation is 200 to 250 mm; mean annual temperature is 8 to 9 degrees C., and the frost-free season is 90 to 120 days.
GEOGRAPHICALLY ASSOCIATED SOILS: These are the
Oxcorel,
Wieland, and
Zaidy soils. Oxcorel and Wieland soils have more than 35 percent clay in the particle-size control section. Zaidy soils are deep and have strongly cemented duripans.
DRAINAGE AND SATURATED HYDRAULIC CONDUCTIVITY: Well drained; slow to medium runoff; moderately high saturated hydraulic conductivity.
USE AND VEGETATION: Livestock grazing and wildlife habitat. The present vegetation is mainly black sagebrush, bottlebrush squirreltail and Sandberg bluegrass.
DISTRIBUTION AND EXTENT: Central Nevada. These soils are of small extent. MLRA 24, 28B.
MLRA SOIL SURVEY REGIONAL OFFICE (MO) RESPONSIBLE: Davis, California
SERIES ESTABLISHED: Lander County, South Part, Nevada, 1985.
REMARKS: Diagnostic horizons and features recognized in this pedon are:
Ochric epipedon - The zone from the surface to 10 cm (A horizon).
Argillic horizon - The zone from 10 to 33 cm (Bt and Btk horizon).
Indurated duripan - The zone from 33 to 152 cm (Bqkm horizon).
Particle-size control section - The zone from the soil surface to 33 cm (A, Bt and Btk horizon).
National Cooperative Soil Survey
U.S.A.