LOCATION WEIMER                  NV+CA

Established Series
Rev. JBF/TM
01/2020

WEIMER SERIES

The Weimer series consists of very deep, poorly drained soils that formed in mixed alluvium and lacustrine sediments derived from volcanic rocks. Weimer soils are on flats of internally drained basins and lake plains. Slopes are 0 to 2 percent. Mean annual precipitation is about 330 mm and the mean annual temperature is about 6 degrees C.

TAXONOMIC CLASS: Very-fine, smectitic, frigid Xeric Epiaquerts

TYPICAL PEDON: Weimer clay - rangeland (Colors for dry soils unless otherwise noted). Vertical cracks 3 to 10 cm wide extend from the soil surface to a depth of 50 cm.

A1--0 to 8 cm; dark gray (10YR 4/1) clay, very dark gray (10YR 3/1) moist; strong very fine granular structure; very hard, friable, very sticky and very plastic; many very fine and fine roots; many fine interstitial pores; neutral (pH 7.2); clear smooth boundary, (8 to 15 cm thick)

A2--8 to 18 cm; dark gray (10YR 4/1) clay, very dark gray (10YR 3/1) moist; strong fine and medium subangular blocky structure; very hard, very firm, very sticky and very plastic; many very fine and fine roots; many very fine interstitial and few fine tubular pores; common pressure cutans; neutral (pH 7.3); clear smooth boundary. (5 to 15 cm thick)

Bss1--18 to 66 cm; dark gray (10YR 4/1) clay, very dark gray (10YR 3/1) moist; strong medium and coarse angular blocky structure; very hard, very firm, very sticky and very plastic; many very fine and fine roots; many very fine interstitial and few fine tubular pores; many slickensides; many wedge-shaped aggregates tilted 30 degrees from horizontal; few fine distinct yellowish brown (10YR 5/4) iron masses on faces of peds; slightly alkaline (pH 7.4); gradual wavy boundary. (30 to 60 cm thick)

Bss2--66 to 122 cm; dark gray (10YR 4/1) clay, very dark gray (10YR 3/1) moist; strong medium and coarse angular blocky structure; very hard, very firm, very sticky and very plastic; few very fine and fine roots; common very fine interstitial and few fine tubular pores; many slickensides; many wedge-shaped aggregates tilted 30 degrees from horizontal; few fine distinct yellowish brown (10YR 5/4) iron masses on faces of peds; slightly effervescent; moderately alkaline (pH 8.4); clear smooth boundary, (40 to 66 cm thick.)

Bk--122 to 157 cm; dark gray (10YR 4/1) clay, very dark grayish brown (10YR 3/2) moist; massive; very hard, very firm, very sticky and very plastic; few very fine roots; few very fine and fine tubular pores; common fine and medium white (10YR 8/1) soft masses of lime; strongly effervescent; moderately alkaline (pH 8.4).

TYPE LOCATION: Washoe County, Nevada in Garden Lake Flat; about 600 feet east and 600 feet south of the north-west corner of Section 12, T. 35 N., R. 18 E.; USGS Burnt Lake 7.5-minute topographic quadrangle; 40 degrees, 55 minutes, 42 seconds north latitude and 119 degrees, 54 minutes, 56 seconds west longitude; WGS84 Decimal Degrees 40.9283333 latitude, -119.9155556 longitude.
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RANGE IN CHARACTERISTICS:
Soil moisture: Moist in winter and spring, ponded for long or very long duration in spring and early summer, dry summer and fall.
Aquic conditions: Saturated within a depth of 50 cm in spring and early summer.
Mean annual soil temperature: 6 to 8 degrees C.
Mean summer soil temperature: 16 to 17 cm.
Depth to carbonates: 50 to 100 cm.
Other features: When dry, vertical cracks 1.25 to 10 cm wide extend from the soil surface to a depth of 50 to 76 cm or more. The cracks are closed in winter to early summer. Gilgai micro relief is evident in most areas.

Particle-size control section - Clay content: 60 to 75 percent

A horizons
Hue: Neutral, 10YR or 2.5Y.
Value: 4 or 5 dry, 2 through 3.5 moist.
Chroma: 0 or 1.
Reaction: Neutral, or slightly alkaline through strongly alkaline in saline phases.
Salinity (EC:) Less than 1 or 8 to 16 mmhos/cm in saline phases.

Bss horizons
Hue: Neutral, 10YR or 2.5Y.
Value: 4 or 5 dry, 2 or 3 moist.
Chroma: 0 or 1.
Structure: Prismatic or angular blocky.
Reaction: Slightly alkaline or moderately alkaline. Slightly alkaline through strongly alkaline in saline phases.
Effervescence: Noneffervescent or slightly effervescent.
Salinity (EC): 0 to 8 mmhos/cm.
Other features: Common or many slickensides and wedge-shaped aggregates. Few or common distinct redox concentrations

Bk horizons:
Hue: Neutral, 10YR or 2.5Y
Value: 4 or 5 dry, 2 or 3 moist
Chroma: 0 through 2
Texture: Clay or silty clay
Reaction: Moderately alkaline or strongly alkaline
Effervescence: Slightly effervescent through strongly effervescent. None to many fine to large soft masses of lime

COMPETING SERIES: No other series have been classified in the same family at the present time.

GEOGRAPHIC SETTING: Weimer soils are on flats of internally drained basins. They formed in alluvium derived from mixed rocks and lacustrine sediments from basalt, andesite and tuff. Slopes are 0 to 2 percent. Elevations are 1,495 to 2,170 meters. The mean annual precipitation is 300 to 360 mm, mean annual temperature is 5 to 7 degrees C, and the frost-free season is 60 to 80 days.

GEOGRAPHICALLY ASSOCIATED SOILS: These are the Boulder Lake, Home Camp, Newlands and Ninemile soils. Boulder Lake soils have chroma greater than 1.5 throughout the control section. Home Camp soils have gravelly clay Bt horizons. Newlands soils have clay loam Bt horizons. Ninemile soils have clay Bt horizons and are shallow to hard volcanic rock.

DRAINAGE AND SATURATED HYDRAULIC CONDUCTIVITY: Poorly drained; ponded or very slow runoff; low saturated hydraulic conductivity. The seasonal water table is perched at 0 to 15 cm during the winter and spring. The soil surface is ponded with water for a short period during the same period in most years.

USE AND VEGETATION: Livestock grazing and wildlife habitat. Juncus, rumex, carex and mat muhly is the principal vegetation.

DISTRIBUTION AND EXTENT: North-western Nevada, north-eastern California. These soils are of small extent.

MLRA SOIL SURVEY REGIONAL OFFICE (MO) RESPONSIBLE: Davis, California

SERIES ESTABLISHED: Surprise Valley-Home Camp Area, California-Nevada, 1963. The name is from Weimer Springs located within the Area.

REMARKS:
Diagnostic horizons and features recognized in this pedon are:
Ochric epipedon - The zone from the soil surface to 18 cm (A1 and A2 horizons).
Vertical cracks - The zone from the soil surface to a depth of 50 cm (A1, A2 and part of the Bss1 horizons).
Slickensides and wedge-shaped aggregates - The zone from 18 to 122 cm (Bss1 and Bss2 horizons).
Redox concentrations - The zone from 18 to 66 cm (Bss1, Bss2 horizons).
Chroma of 1 or less - The zone from the soil surface to 122 cm (A1, A2, Bss1, Bss2 horizons).

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National Cooperative Soil Survey
U.S.A.