LOCATION PRUNIE NV
Established Series
Rev. CEJ/WED/JVC/JBF
06/2017
PRUNIE SERIES
The Prunie series consists of deep, well drained soils that formed in colluvium and residuum derived from volcanic rocks. Prunie soils are on mountains and plateaus. Slopes are 4 to 15 percent. The mean annual precipitation is about 400 mm and the mean annual temperature is about 7 degrees C.
TAXONOMIC CLASS: Fine, smectitic, frigid Aridic Argixerolls
TYPICAL PEDON: Prunie very stony loam--rangeland. (Colors are for dry soil unless otherwise noted.) The soil surface has 15 percent cover with stones.
A1--0 to 10 cm; brown (10YR 5/3) very stony loam, very dark brown (10YR 2/2) moist; moderate medium subangular blocky structure; slightly hard, friable, slightly sticky and slightly plastic; many very fine, fine and medium roots, common coarse roots; many very fine, fine and medium tubular and interstitial pores; 15 percent gravel, 10 percent cobbles, and 10 percent stones; neutral (pH 6.7); clear smooth boundary. (8 to 15 cm thick)
A2--10 to 25 cm; dark grayish brown (10YR 4/2) very cobbly loam, very dark brown (10YR 2/2) moist; moderate medium subangular blocky structure; slightly hard, friable, slightly sticky and slightly plastic; many very fine, fine, medium and coarse roots; many very fine, fine and common medium tubular pores; 10 percent gravel, 20 percent cobbles, and 5 percent stones; neutral (pH 6.7); abrupt smooth boundary. (13 to 23 cm thick)
Bt1--25 to 36 cm; brown (7.5YR 5/4) gravelly clay loam, dark reddish brown (5YR 3/3) moist; moderate fine and medium prismatic structure; hard, firm, moderately sticky and moderately plastic; many very fine, fine, medium and coarse horizontal roots; common very fine and fine tubular pores; many distinct and common prominent clay films on faces of peds and lining pores; 20 percent gravel; neutral (pH 6.8); clear wavy boundary. (10 to 15 cm thick)
Bt2--36 to 79 cm; brown (7.5YR 4/4) gravelly clay, dark reddish brown (5YR 3/4) moist; strong fine and medium angular blocky structure; very hard, firm, very sticky and very plastic; few medium roots; common very fine, fine and medium tubular pores; many prominent clay films on faces of peds and lining pores; 20 percent gravel; neutral (pH 7.2); clear smooth boundary. (25 to 60 cm)
Bt3--79 to 114 cm; brown (7.5YR 4/4) clay, dark reddish brown (5YR 3/3) on moist faces of peds; strong fine and medium angular blocky structure; very hard, firm, very sticky and very plastic; few very fine roots; few fine tubular pores; common distinct clay films on faces of peds and lining pores; slightly alkaline (pH 7.4); clear smooth boundary. (30 to 50 cm thick)
Cr--114 to 132 cm; highly weathered basalt; clear smooth boundary.
R--132 cm; hard, unweathered basalt.
TYPE LOCATION: Washoe County, Nevada; west of the Virginia Mountains near Spanish Flat; approximately 1,200 feet east and 1,900 feet north of the southwest corner of section 24, T. 25 N., R. 19 E.; USGS Spanish Flat 7.5 minute topographic quadrangle; latitude 40 degrees 01 minute 03 seconds N and longitude 119 degrees 48 minutes 16 seconds W; WGS84 Decimal Degrees 40.0175000 latitude, -119.8044444 longitude.
RANGE IN CHARACTERISTICS:
Soil moisture: Usually moist in winter and spring, dry in summer and fall; aridic soil moisture regime that borders on xeric.
Mean annual soil temperature: 6 to 8 degrees C.
Mollic epipedon thickness: 25 to 40 cm; does not include the Bt1 horizon.
Depth to bedrock: 100 to 150 cm to a paralithic contact. The paralithic materials below the contact are highly weathered volcanic rock. Harder, less weathered bedrock is within 150 cm of the soil surface.
Particle-size control section - Clay content: 40 to 60 percent.
A horizons
Value: 4 or 5 dry, 2 or 3 moist.
Chroma: 2 or 3, dry or moist.
Organic matter content: 1 to 3 percent.
Bt1 horizon
Texture: Clay loam or gravelly clay loam.
Bt2 horizon
Value: 4 or 5 dry.
Chroma: 3 or 4, dry or moist.
Clay content: 40 to 60 percent.
Rock fragments: 15 to 35 percent.
Bt3 horizon
Value: 4 or 5 dry 3 or 4 moist.
Chroma: 3 or 4, dry or moist.
Clay content: 60 to 70 percent.
Rock fragments: 0 to 10 percent
COMPETING SERIES: These are the
Alyan and
Walti series.
Alyan and
Walti soils have bedrock within 100 cm of the soil surface.
GEOGRAPHIC SETTING: Prunie soils are on mountain and plateaus. They typically occur on slightly concave footslope positions. These soils formed in residuum and colluvium derived from volcanic rocks. Slopes are 4 to 15 percent. Elevations range from 1,830 to 2,450 meters. The climate is semiarid with cool, moist winters and warm, dry summers. The mean annual precipitation is 360 to 400 mm, the mean annual temperature is 6 to 7 degrees C, and the frost-free period is 50 to 75 days.
GEOGRAPHICALLY ASSOCIATED SOILS: These are the
Gabica,
Softscrabble,
Sumine, and
Thulepah soils. Gabica soils are shallow to bedrock. Softscrabble and Sumine soils are loamy-skeletal. Thulepah soils are fine-loamy and have a cryic soil temperature regime.
DRAINAGE AND SATURATED HYDRAULIC CONDUCTIVITY: Well drained; high surface runoff; low saturated hydraulic conductivity.
USE AND VEGETATION: Prunie soils are used for rangeland and wildlife habitat. The present vegetation is mainly low sagebrush, bluebunch wheatgrass, Sandberg's bluegrass, Hooker's balsamroot, and currant.
DISTRIBUTION AND EXTENT: Western Nevada. These soils are not extensive with about 2,000 acres of the series mapped to date. MLRA 26.
MLRA SOIL SURVEY REGIONAL OFFICE (MO) RESPONSIBLE: Davis, California.
SERIES ESTABLISHED: Washoe County, Nevada, Central Part, 1990. The name is coined.
REMARKS: Diagnostic horizons and features recognized in this pedon are:
Mollic epipedon - The zone from the soil surface to 25 cm (A1 and A2 horizons).
Argillic horizon - The zone from 25 to 114 cm (Bt1, Bt2, and Bt3 horizons).
Paralithic contact - The boundary at 114 cm to underlying weathered bedrock (Cr layer).
Lithic contact - The boundary at 132 cm to the unweathered bedrock(R layer).
Particle-size control section - The zone from 25 to 75 cm (Bt1 horizon and part of the Bt2 horizon).
National Cooperative Soil Survey
U.S.A.