LOCATION ALVODEST OR+NV

Established Series
Rev. RDK/TDT/JBF
01/2023

ALVODEST SERIES

The Alvodest series consists of very deep, somewhat poorly to moderately well drained soils that formed in lacustrine sediments. Alvodest soils are on basin floors and have slopes of 0 to 3 percent. The mean annual precipitation is about 200 mm and the mean annual temperature is about 8 degrees C.

TAXONOMIC CLASS: Fine, smectitic, mesic Sodic Aquicambids

TYPICAL PEDON: Alvodest silty clay loam on a 1 percent slope, rangeland. (Colors are for dry soil unless otherwise noted.)

Aknz1--0 to 5 cm; light gray (10YR 7/2) silty clay loam, brown (10YR 4/3) moist; strong medium and fine angular blocky structure; hard, friable, sticky and plastic; many fine and medium roots; many very fine and fine vesicular pores; strongly effervescent-calcium carbonate is 9 percent, EC is 40 mmhos/cm, SAR is 990; very strongly alkaline (pH 9.7); clear smooth boundary. (3 to 10 cm thick)

Aknz2--5 to 15 cm; light brownish gray (10YR 6/2) silty clay loam, dark brown (10YR 3/3) moist; weak fine subangular blocky structure; soft, very friable, sticky and plastic; many fine and medium roots; many very fine and fine vesicular and irregular pores; strongly effervescent-calcium carbonate is 9 percent, EC is 40 mmhos/cm, SAR is 990; very strongly alkaline (pH 9.5); clear smooth boundary. (5 to 30 cm thick)

Bknz1--15 to 38 cm; grayish brown (10YR 5/2) silty clay, dark brown (10YR 3/3) moist; moderate medium angular blocky structure; hard, friable, sticky and plastic; many fine and medium roots; many very fine and fine irregular pores; few faint stress surfaces; strongly effervescent-calcium carbonate is 9 percent, EC is 27 mmhos/cm, SAR is 685; very strongly alkaline (pH 9.8); clear smooth boundary. (18 to 28 cm thick)

Bknz2--38 to 53 cm; grayish brown (10YR 5/2) silty clay, very dark grayish brown (10YR 3/2) moist; moderate medium angular blocky structure; hard, firm, sticky and plastic; common fine and medium roots; many very fine and fine irregular pores; common faint stress surfaces; strongly effervescent-calcium carbonate is 9 percent, EC is 27 mmhos/cm, SAR is 685; very strongly alkaline (pH 9.8); clear smooth boundary. (10 to 20 cm thick)

Bknz3--53 to 107 cm; grayish brown (10YR 5/2) silty clay, very dark grayish brown (10YR 3/2) moist; moderate coarse prismatic structure; hard, firm, sticky and plastic; common fine and medium roots; many very fine and fine irregular pores; few faint stress surfaces; strongly effervescent-calcium carbonate is 8 percent, EC is 14 mmhos/cm, SAR is 70; very strongly alkaline (pH 9.9); gradual smooth boundary. (43 to 64 cm thick)

Bknz4--107 to 135 cm; light brownish gray (10YR 6/2) silty clay, very dark grayish brown (10YR 3/2) moist; moderate medium prismatic structure; hard, firm, sticky and plastic; few fine roots; many very fine and fine irregular pores; few faint stress surfaces; strongly effervescent-calcium carbonate is 16 percent, EC is 26 mmhos/cm, SAR is 795; very strongly alkaline (pH 10.0); gradual smooth boundary. (23 to 33 cm thick)

Ckz--135 to 198 cm; light gray (10YR 7/2) silty clay, brown (10YR 5/3) moist; massive; hard, firm, sticky, plastic; many very fine and fine irregular pores; strongly effervescent-salts evident on face of profile; very strongly alkaline (pH 9.0).

TYPE LOCATION: Harney County, Oregon; about 3.5 miles east of Fields in the SW1/4 NE1/4 section 21, T. 38 S., R. 35 E.; latitude 42 degrees 15 minutes 36 seconds N and longitude 118 degrees 36 minutes 39 seconds W; NAD 83.

RANGE IN CHARACTERISTICS:
Soil Moisture: Usually dry, but in most years are saturated with water within 100 cm of the surface in late winter and spring.
Mean annual soil temperature: 8 to 10 degrees C.
Reaction: Very strongly alkaline throughout.
Salinity (EC): Greater than 16 mmhos/cm. throughout the profile and is highest in the surface.

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

A horizon
Value: 6 or 7, and 3 or 4 moist.
Chroma: 2 or 3 moist and dry.
Sodicity (SAR): 800 to 1,000.
Other features: 0.5 to 1.0 percent organic matter.

B horizon
Value: 5 through 7 dry, 3 or 4 moist.
Chroma: 2 dry, 2 or 3 moist.
Texture: silty clay, clay or silty clay loam with 35 to 60 percent clay. Sodicity (SAR): 70 to 700.
Other features: angular blocky or prismatic.

C horizon
Value: 6 through 8 dry, 3 through 5 moist.
Chroma: 2 or 3 moist and dry.
Texture: silty clay loam, silty clay or loam with 25 to 50 percent clay.

COMPETING SERIES: This is the Droval series. Droval soils have an SAR of 45 to 80 and contain 1 to 3 percent gypsum in the subsoil.

GEOGRAPHIC SETTING: The soils are on basin floors at elevations of 1,200 to 1,500 meters. Slopes are 0 to 3 percent. The soils formed in lacustrine sediment. The climate is characterized by cool moist winters and hot dry summers. The mean annual precipitation is 180 to 250 mm. The mean annual temperature is 7 to 10 degrees C. The frost-free period is 80 to 110 days.

GEOGRAPHICALLY ASSOCIATED SOILS: These are the Boravall, Catlow, Davey, Defenbaugh, the competing Droval, Enko and Goldrun soils. Goldrun soils are sandy throughout and are on sand dunes. Boravall soils are poorly drained and have an aquic moisture regime. Catlow soils are loamy-skeletal and are on old beach terraces. Davey soils have sandy particle-size control section. Defenbaugh soils have a fine-loamy particle-size control section. Enko soils have a coarse-loamy particle-size control section.

DRAINAGE AND PERMEABILITY: Somewhat poorly to moderately well drained; slow permeability; moderately low saturated hydraulic conductivity. Flooding is none to rare. A water table is at 15 cm above the surface to 76 cm below the surface from December to April.

USE AND VEGETATION: The soils are used for livestock grazing. Vegetation is black greasewood, basin wildrye and inland saltgrass.

DISTRIBUTION AND EXTENT: Southeastern Oregon, and Northwestern Nevada; MLRA 24. The series is of moderate extent.

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

SERIES ESTABLISHED: Lake County, Oregon, Southern Part, 1991.

REMARKS: Diagnostic horizons and features recognized in this pedon are:
Ochric epipedon - The zone from 0 to 18 cm (A and part of the Bknz1 horizons).
Cambic horizon - The zone from 15 to 107 cm (Bknz1, Bknz2 and Bknz3 horizons).
Sodic intergrade - SAR is above 70 throughout the profile.
Aquic conditions: The soil is saturated for 90 or more consecutive days above 100 cm.
Particle-size control section - The zone from 25 to 100 cm (Bknz2 and part of Bknz1 and Bknz3 horizons.

Drainage, water table and ponding depths should be reviewed and verified during the update process.

ADDITIONAL DATA: Reference sample S82OR-025-007.

National Cooperative Soil Survey
U.S.A.