LOCATION STATZ              OR
Established Series
Rev. JSC/TDT
07/2003

STATZ SERIES


The Statz series consists of shallow to a duripan, well drained soils that formed in ash over material weathered from lava rocks. Statz soils are on lava plains and have slopes of 0 to 30 percent. The mean annual precipitation is about 11 inches and the mean annual temperature is about 47 degrees F.

TAXONOMIC CLASS: Loamy, mixed, superactive, mesic, shallow Vitritorrandic Durixerolls

TYPICAL PEDON: Statz ashy sandy loam, on a 1 percent slopes at elevation of 3,640 feet in juniper woodland. (Colors are for dry soil unless otherwise noted. When described the soil was moist throughout.)

A1--0 to 4 inches; grayish brown (10YR 5/2) ashy sandy loam, very dark grayish brown (10YR 3/2) moist; weak thin platy structure; soft, very friable, slightly sticky and nonplastic; many very fine roots; many very fine pores; neutral (pH 7.3); clear wavy boundary. (3 to 6 inches thick)

A2--4 to 9 inches; brown (10YR 5/3) ashy sandy loam, very dark grayish brown (10YR 3/2) moist; massive; soft, very friable, slightly sticky and nonplastic; common roots, many very fine pores; slightly alkaline (pH 7.8); abrupt smooth boundary. (4 to 8 inches thick)

2Bkq--9 to 16 inches; pale brown (10YR 6/3) sandy loam, dark brown (10YR 3/3) moist; massive; firm and brittle; few roots; many very fine pores; strongly effervescent; moderately alkaline (pH 8.4); abrupt smooth boundary. (0 to 9 inches thick)

2Bkqm--16 to 27 inches; pale brown (10YR 6/3) duripan, dark brown (10YR 3/3) moist; platy; indurated; reticulate pattern of opal veins about 1 millimeter thick in plates; tops of some plates have an opal cap 1 millimeter thick; slightly effervescent. (7 to 15 inches thick)

3R--27 inches; basalt

TYPE LOCATION: Crook County, Oregon; 300 feet north of trail fork; SE1/4 SE1/4 section 8, T. 17 S., R. 16 E.

RANGE IN CHARACTERISTICS: The mean annual soil temperature ranges from 47 to 52 degrees F. Soils are moist in winter and spring. They are warmer than 41 degrees F from March 15 to November 1, and they are dry in this period after July 1. Depth to the duripan is 10 to 20 inches. Depth to bedrock is 20 to 40 inches. The solum has 0 to 15 percent gravel and 5 to 15 percent clay. The solum has a phosphate retention of 15 to 25 percent, 10 to 30 percent glass and glass-coated aggregate, and acid oxalate extractable aluminum plus one-half the acid oxalate iron of 0.4 to 0.8 percent.

The A horizon has chroma of 2 or 3 moist and dry. It has 0 to 15 percent gravel and 0 to 15 percent stones and cobbles. It is neutral or slightly alkaline.

The 2Bkq horizon is sandy loam or loam. It may contain durinodes or lack brittleness in some pedons. It is noncalcareous to strongly calcareous.

The duripan commonly extends into the bedrock fractures.

COMPETING SERIES: This is the Whiteye series. Whiteye soils have an argillic horizon.

GEOGRAPHIC SETTING: Statz soils are on lava plains at elevation of 2,000 to 4,800 feet. Slopes are 0 to 30 percent. The soils formed in ash over material weathered from scoria, basalt, and other hard volcanic rocks. The mean annual precipitation is 8 to 12 inches. The average January temperature is 63 to 66 degrees F, and the mean annual temperature is 47 to 52 degrees F. The frost-free period is 70 to 100 days.

GEOGRAPHICALLY ASSOCIATED SOILS: These are the Deschutes and Searles soils. Deschutes soils lack a duripan. Searles soils lack a duripan and have an argillic horizon.

DRAINAGE AND PERMEABILITY: Well drained; permeability is moderately rapid above the duripan and very slow through the duripan.

USE AND VEGETATION: Livestock grazing and wildlife habitat. Native vegetation is bluebunch wheatgrass, Idaho fescue, antelope bitterbrush, mountain big sagebrush and western juniper.

DISTRIBUTION AND EXTENT: Central Oregon east of the Cascade Mountains; MLRA 10. The soils are moderate in extent.

MLRA SOIL SURVEY REGIONAL OFFICE (MO) RESPONSIBLE: Portland, Oregon

SERIES ESTABLISHED: Upper Deschutes River Area, Oregon, 1992.

REMARKS: Diagnostic horizons and other features:

Mollic epipedon - the zone from 0 to 9 inches (A1 and A2 horizons)

Duripan - the zone from 16 to 27 inches (2Bkqm horizon)

Vitritorrandic - the zone from 0 to 9 inches has over 5 percent glass and over 0.4 percent acid oxalate extractable aluminum plus one-half the acid oxalate iron. This data is based on the associated Deschutes Series.

ADDITIONAL DATA: Soil characterization data on two pedons (S79-OR-013-1 and S79-OR-013-2) reported in Oregon State University Soils Laboratory Report for Statz soils sampled in Crook County, Oregon.


National Cooperative Soil Survey
U.S.A.