LOCATION BOULDER LAKE NV+CA ID OR

Established Series
Rev. JBF-TM
10/2018

BOULDER LAKE SERIES

The Boulder Lake series consists of very deep, somewhat poorly drained soils that formed in lacustrine deposits and alluvium derived mainly from volcanic rocks. Boulder Lake soils are on depressions on plateaus and on lake plains. Slopes are 0 to 2 percent. The mean annual precipitation is about 360 mm and the mean annual temperature is about 6 degrees C.

TAXONOMIC CLASS: Fine, smectitic, frigid Xeric Epiaquerts

TYPICAL PEDON: Boulder Lake clay--rangeland. (Colors are for moist soil unless otherwise noted.)

A--0 to 5 cm; very dark grayish brown (10YR 3/2) clay, grayish brown (10YR 5/2) dry; strong very fine and fine granular structure; slightly hard, friable, very sticky and very plastic; root crowns only; many very fine and fine interstitial pores; slightly acid (pH 6.4); abrupt smooth boundary. (1 to 20 cm thick)

Bw--5 to 10 cm; dark grayish brown (10YR 4/2) clay, grayish brown (10YR 5/2) dry; moderate medium prismatic structure; slightly hard, friable, very sticky and very plastic; few very fine, fine and medium roots; many very fine and fine interstitial pores; neutral (pH 6.6); abrupt wavy boundary. (0 to 13 cm thick)

Bss1--10 to 15 cm; dark grayish brown (10YR 4/2) clay, grayish brown (10YR 5/2) dry; moderate coarse prismatic structure and strong very fine and fine angular blocky; slightly hard, friable, very sticky and very plastic; many very fine, few fine and medium roots; few very fine and fine tubular, and many very fine and fine interstitial pores; few slickensides; neutral (pH 6.6); clear wavy boundary. (5 to 50 cm thick)

Bss2--15 to 61 cm; dark grayish brown (10YR 4/2) clay, light brownish gray (10YR 6/2) dry; moderate medium prismatic structure; very hard, firm, very sticky and very plastic; few very fine, fine and medium roots; few fine tubular and many very fine interstitial pores; common slickensides; few fine and medium distinct brown (7.5YR 4/4) and very dark brown (7.5YR 2.5/2) masses of iron and manganese accumulation; neutral (pH 6.8); gradual smooth boundary. (30 to 76 cm thick)

Bss3--61 to 157 cm; dark grayish brown (10YR 4/2) clay, light brownish gray (10YR 6/2) dry; weak coarse prismatic structure and strong medium through very coarse angular blocky; very hard, firm, very sticky and very plastic; few fine and medium roots; few fine tubular and many very fine interstitial pores; common slickensides; common fine distinct brown (7.5YR 4/4) and dark brown (7.5YR 3/4) masses of iron accumulation; few fine and medium faint very dark brown (10YR 2/2) masses of manganese accumulation; neutral (pH 6.8).

TYPE LOCATION: Washoe County, Nevada; about 0.75 miles west of Boulder Lake; near the center of section 9, T. 40 N., R. 19 E.; USGS Boulder Lake 7.5 minute topographic quadrangle; latitude 41 degrees 23 minutes 44 seconds N and longitude 119 degrees 51 minutes 37 seconds W; WGS84 Decimal Degrees 41.3955556 latitude, -119.8602778 longitude.

RANGE IN CHARACTERISTICS:
Soil moisture: Usually ponded for less than 45 consecutive days in most years, mainly in the spring; brief ponding occurs after intensive rainfall. Saturated to a depth of 76 to 150 cm in late winter and spring; Seasonal periods of aquic moisture regime when the soil moisture control section is saturated and reduced.
Mean annual soil temperature: 6 to 8 degrees C.
Mean summer soil temperature: 17 to 18 degrees C.
Effervescence: Noneffervescent or slightly effervescent but ranges to strongly effervescent in some pedons where few to common, very fine to medium filaments or masses of carbonate occur below depths of 50 cm.
Other features: Reversible trans-horizon cracks are normally open to the soil surface during summer and early fall, are up to 8 cm wide, and are 8 to 15 cm apart. They decrease in width with increasing depth. Cracks remain open for fewer than 180 consecutive days.

Particle-size control section - Clay content: Averages 40 to 60 percent.

A horizon
Hue: 10YR or 2.5Y.
Value: 3 through 5 moist, 5 or 6 dry.
Chroma: 2 or 3 moist, 1 through 3 dry.
Reaction: Slightly acid through slightly alkaline.

Bw horizon (when present) and Bss horizons
Hue: 10YR through 5Y.
Chroma: 2 or 3, moist or dry; some pedons have dry chroma of 1 in the Bss1 horizon; dominantly chroma 2 or less above 51 cm.
Texture: Clay or silty clay.
Structure: Moderate or strong, very fine to very coarse prismatic, medium to very coarse angular blocky in the upper part and weak to strong, medium to very coarse prismatic and moderate or strong, medium to very coarse angular in the lower subhorizons.
Consistence: Very hard or extremely hard, dry; firm or very firm, moist; may be slightly hard and friable in the upper subhorizon.
Redoximorphic features: Few or common, very fine to medium, distinct or prominent, redox concentrations of iron and manganese with reddish, yellowish and brownish colors that have hue of 10YR through 5YR and chroma of 2 through 6.
Reaction: Neutral through moderately alkaline.
Vertic features: Few too many slickensides and many pressure cutans. Soil is interpreted as having reduced matrix colors and redox concentrations due to saturation.

Bk horizon (when present)
Hue: 10YR through 5Y.
Value: 5 through 7, moist or dry.
Chroma 2 through 6, moist or dry.
Texture: Silty clay loam or clay loam.
Clay content: 35 to 40 percent.
Reaction: Slightly alkaline or moderately alkaline.

COMPETING SERIES: This is the Chancelakes series. Chancelakes soils have albic horizons, argillic horizons, and ashy surface textures.

GEOGRAPHIC SETTING: Boulder Lake soils are on depressions on plateaus and on lake plains. These soils formed in lacustrine deposits derived mainly from volcanic rocks such as tuff, basalt, and andesite. Gilgai microrelief is evident in most areas. Slopes are 0 to 2 percent. Elevations range from 1,400 to 2,200 meters. The climate is semiarid with cool, moist winters and warm, dry summers. The mean annual precipitation is 230 to 510 mm, the mean annual temperature is 5 to 8 degrees C, and the frost-free period is 50 to 90 days.

GEOGRAPHICALLY ASSOCIATED SOILS: These are the Disabel and Schamp soils. Disabel and Schamp soils have clayey argillic horizons and are well drained.

DRAINAGE AND SATURATED HYDRAULIC CONDUCTIVITY: Somewhat poorly drained; negligible through very high surface runoff; moderately low saturated hydraulic conductivity. These soils are susceptible to occasional or frequent ponding for long duration from December through June with water up to two feet deep. Some areas are also susceptible to rare ponding for brief or very brief duration during summer and fall months. Ponding is a result of surface runoff from higher-lying soils and is less than 45 consecutive days in most years.

USE AND VEGETATION: Boulder Lake soils are used for livestock grazing and wildlife habitat. The vegetation is mainly silver sagebrush, Nevada bluegrass, mat muhly, poverty weed, and primrose, with some Carex and Rumex species.

DISTRIBUTION AND EXTENT: Northern Nevada, northeastern California, south-central Oregon, and southwestern Idaho. These soils are moderately extensive. The series concept and main acreage is in MLRA 23, while other acreage occurs in MLRAs 21 and 25.

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

SERIES ESTABLISHED: Washoe County (Surprise Valley-Home Camp Area), Nevada, 1974.

REMARKS: Diagnostic horizons and features recognized in this pedon are:
Ochric epipedon - The zone from the soil surface to 18 cm (A, Bw and part of the Bss1 horizons).
Slickensides - The zone from 10 to 152 cm (Bss1, Bss2, and Bss3 horizons).
Particle-size control section - The zone from 25 to 100 cm (parts of the Bss2 and Bss3 horizons).

National Cooperative Soil Survey
U.S.A.