LOCATION WASPO              NV

WASPO SERIES

TAXONOMIC CLASS: Fine, smectitic, mesic Aridic Haploxererts

TYPICAL PEDON: Waspo clay, rangeland. (Colors are for dry soil unless otherwise noted.)

Al--0 to 7 inches; dark grayish brown (10YR 4/2) clay, brown (10YR 4/3) moist; moderate medium prismatic structure, extremely hard, very firm, very sticky and very plastic; few medium and coarse roots, few medium and large pores; 10 percent pebbles; slightly acid (pH 6.5); gradual wavy boundary. (6 to l0 inches thick)

A2--7 to 24 inches; dark grayish brown (10YR 4/2) clay, brown (10YR 4/3) moist; moderate coarse prismatic structure; extremely hard, very firm, very sticky and very plastic; few medium and coarse roots, few medium and large pores; many intersecting slickensides; 10 percent pebbles; slightly acid; (pH 6.5); gradual wavy boundary. (14 to 34 inches)

Cr--24 inches; light gray weathered tuff.

TYPE LOCATION: Washoe County, Nevada; about 6 miles west of Reno; in the southeast 1/4 of southwest 1/4 of section 10, T. 19 N., R. 18 E.

RANGE IN CHARACTERISTICS:

Mean annual soil temperature: 52 to 54 degrees F.
Depth to the paralithic contact: 20 to 40 inches.
Cracks: The soil has cracks 1 to 2 centimeters wide that remain open in most years from June to November. The cracks are generally closed the rest of the year. In most years the cracks extend to the weathered rock.
Profile reaction: commonly slightly acid or neutral, but are mildly alkaline in the lower part above the bedrock in some pedons.
Other features: The stoniness classes range up through class 2. Some pedons have a thin pale brown clay C horizon above the weathered bedrock. The weathered bedrock is usually tuff but unrelated very soft sandstone is in some pedons.

Control section - Rock fragments: 5 to 15 percent, mainly tuffaceous gravel are throughout the profile.
Clay content: 45 to 60 percent clay.

A horizon - Hue: 10YR or 7.5YR
Value: 4 or 5 dry
Chroma: 2 or 3 dry, and 3 or 4 moist
Texture: Clay
Structure: medium or coarse prismatic structure, but the immediate surface is fine granular in some pedons.

COMPETING SERIES: These are the Doten, Karcal, Manogue and Moroni series. Doten, Manogue, and Moroni soils lack bedrock within 40 inches. Karcal soils have a lithic contact at a depth of 20 to 30 inches.

GEOGRAPHIC SETTING: Waspo soils are on side slopes of pediments and uplands at elevations of 3,400 to 5,200 feet. Slopes are 2 to 50 percent. The soils formed in mixed pedisediment and residuum weathered from tuff. The climate is semiarid, with hot dry summers and cold moist winters. The mean annual temperature is 49 to 52 degrees F. The mean annual precipitation is 8 to 12 inches. The average frost-free season is about 100 days.

GEOGRAPHICALLY ASSOCIATED SOILS: These are the Chalco and Reno soils. Chalco soils have an argillic horizon and weathered bedrock within 20 inches. Reno soils have an argillic horizon and a duripan.

DRAINAGE AND PERMEABILITY: Well drained; rapid runoff; very slow permeability.

USE AND VEGETATION: Most of these soils are used for wildlife habitat and some livestock grazing. Vegetation is principally rabbitbrush, big sagebrush, horsebrush, cheatgrass, and some bitterbrush. Some of these soils are now being used for urban development.

DISTRIBUTION AND EXTENT: Western Nevada and southern Oregon. These soils are inextensive.

MLRA OFFICE RESPONSIBLE: Reno, Nevada

SERIES ESTABLISHED: Washoe County (South Part), Nevada, 1980.