LOCATION MESMAN OREstablished Series
TAXONOMIC CLASS: Fine-loamy, mixed, superactive, mesic Xeric Natrargids
TYPICAL PEDON: Mesman fine sandy loam--rangeland. (Colors are for dry soil unless otherwise noted.)
An--0 to 9 inches; light brownish gray (10YR 6/2) fine sandy loam, dark brown (10YR 3/3) moist; moderate medium granular structure parting to weak fine subangular blocky; soft, very friable, slightly sticky and slightly plastic; many very fine to coarse roots; slightly effervescent, SAR is 26; EC is 3.9 mmhos/cm; strongly alkaline (pH 8.9); abrupt smooth boundary. (2 to 15 inches thick)
2Btn--9 to 20 inches; pale brown (10YR 6/3) sandy clay loam, brown (10YR 4/3) moist; weak very fine prismatic parting to moderate fine platy structure; slightly hard, friable, moderately sticky and slightly plastic; common very fine roots; few, very fine discontinuous random vesicular pores; common distinct clay films on faces of peds; slightly effervescent (calcium carbonate is a trace); carbonates are disseminated; SAR is 54; EC is 28 mmhos/cm; moderately alkaline (pH 8.2); abrupt smooth boundary. (4 to 12 inches thick)
3Bkn1--20 to 25 inches; pale brown (10YR 6/3) silt loam, brown (10YR 4/3) moist; massive; slightly hard, firm, slightly sticky and slightly plastic; few very fine roots; slightly effervescent (1 percent calcium carbonate); secondary carbonates segregated in common medium irregular seams and filaments; SAR is 61; EC is 43 mmhos/cm; moderately alkaline (pH 8.0); clear wavy boundary. (5 to 15 inches thick)
4Bkn2--25 to 35 inches; pale brown (10YR 6/3) very fine sandy loam, brown (10YR 4/3) moist; massive; soft, friable, nonsticky and slightly plastic; few very fine roots; 5 percent fine gravel; slightly effervescent; secondary carbonates segregated in few medium irregular seams and filaments; moderately alkaline (pH 8.0); clear wavy boundary. (2 to 12 inches thick)
4Bkn3--35 to 60 inches; pale brown (10YR 6/3) silt loam, brown (10YR 4/3) moist; massive; hard, brittle, extremely firm, slightly sticky and slightly plastic; slightly effervescent (3 percent calcium carbonate); SAR is 53; EC is 31 mmhos/cm; moderately alkaline (pH 8.1).
TYPE LOCATION: Lake County, Oregon; in the Warner Valley about 4 miles north-northeast of Plush; in the SE 1/4 of the SW 1/4 of the NE 1/4 of section 4, T. 36 S., R. 24 E.; USGS Plush 7.5 minute topographic quadrangle; 42 degrees 28 minutes 36 seconds north latitude and 119 degrees 53 minutes 25 seconds west longitude, NAD27.
RANGE IN CHARACTERISTICS:
Soil moisture - Usually moist in winter and spring, dry in summer and fall; These soils are dry for more than half the time when soil temperature is greater than 41 degrees F. The soil temperature is above 41 degrees F from about March 15 to about November 15; Aridic moisture regime that borders on xeric.
Mean annual soil temperature - 47 to 50 degrees F.
Depth to base of natric horizon - 15 to 30 inches.
Depth to bedrock - Greater than 60 inches.
Particle-size control section - Clay content: 18 to 35 percent; Sand content: 25 to 50 percent, most of which is very fine sand and fine sand.
An horizon - Value: 5 through 7 dry, 3 or 4 moist.
Chroma: 2 or 3, dry or moist.
Structure: Granular or subangular blocky.
Reaction: Slightly alkaline through strongly alkaline.
Salinity (EC): 2 to 8 mmhos/cm.
Sodicity (SAR): 5 to 30.
2Btn horizon - Hue: 10YR or 7.5YR.
Value: 5 through 6 dry, 3 through 5 moist.
Chroma: 2 or 3, dry or moist.
Texture: Loam, clay loam, silty clay loam, or sandy clay loam.
Clay content: 18 to 35 percent.
Structure: Prismatic or columnar parting to blocky or platy.
Reaction: Moderately alkaline or strongly alkaline.
Salinity (EC): 16 to 32 mmhos/cm.
Sodicity (SAR): 25 to 70.
3Bkn and 4Bkn horizons - Value: 6 through 8 dry, 3 through 6 moist.
Chroma: 2 through 4, dry or moist.
Texture: Very fine sandy loam, silt loam, loam, or clay loam.
Clay content: 10 to 30 percent.
Structure: Massive but ranges to strong fine and medium angular blocky. Structure is due to consolidation and compaction of the lacustrine sediments (rock structure). Some pedons are single grain.
Salinity (EC): 16 to 43 mmhos/cm.
Sodicity (SAR): 20 to 70.
Calcium carbonate equivalent: 1 to 5 percent.
Other features: Lenses of white volcanic ash are present in some pedons.
COMPETING SERIES: These are the Antelope Springs, Calnat, Slipback, Tannawasha (T), and Wespac series.
Antelope Springs soils have hue of 5YR or 7.5YR. Calnat soils are moderately deep to paralithic contacts. Slipback soils have a mean annual soil temperature of 53 to 57 degrees F. and have texture of coarse sandy loam or loamy coarse sand below the natric horizon. Tannawasha soils are moderately deep to lithic contacts. Wespac soils have a mean annual soil temperature of 53 to 56 degrees F.
GEOGRAPHIC SETTING: Mesman soils are on lake terraces. These soils formed in lacustrine deposits with surface mantles of eolian sand. Slopes are 0 to 15 percent. Elevations range from 4,200 to 4,800 feet. The climate is semiarid and characterized by cool, moist winters and warm, dry summers. The mean annual precipitation is 8 to 10 inches, the mean annual temperature is 45 to 50 degrees F., and the frost-free period is 80 to 110 days.
GEOGRAPHICALLY ASSOCIATED SOILS: These are the Helphenstein, Icene, Reese, and Turpin soils. Helphenstein soils are somewhat poorly drained and have EC that is less than 16 mmhos/cm. Icene soils are moderately well drained and have a salic horizon. Reese soils are poorly drained have a very strongly sodic and saline surface and are strongly alkaline throughout. Turpin soils are very strongly alkaline throughout and have EC that is less than 16 mmhos/cm.
DRAINAGE AND PERMEABILITY: Well drained; medium or high surface runoff; slow permeability.
USE AND VEGETATION: Mesman soils are used for livestock grazing and wildlife habitat. The native vegetation is basin big sagebrush, Wyoming big sagebrush, spiny hopsage, black greasewood, Indian ricegrass, basin wildrye, and creeping wildrye.
DISTRIBUTION AND EXTENT: South-central Oregon. These soils are moderately extensive. MLRA 23.
MLRA OFFICE RESPONSIBLE: Reno, Nevada.
SERIES ESTABLISHED: Lake County (Southern Part), Oregon, 1991.
REMARKS: Diagnostic horizons and features recognized in this pedon are:
Ochric epipedon - The zone from the soil surface to 9 inches (An horizon).
Natric horizon - The zone from about 9 to 20 inches (2Btn horizon).
Identifiable secondary carbonates - The zone from 20 to 35 inches (3Bkn1 and 4Bkn2 horizons).
Particle-size control section - The zone from 9 to 20 inches (2Btn horizon).
The superactive cation exchange activity class was added in 03/2003 to the taxonomic classification by the National Soil Survey Center on request of the Reno MLRA office, without review of the soil series property data.
ADDITIONAL DATA: The typical pedon at the series type location is reference sampled by the Soil Survey Laboratory (SSL), Lincoln, NE, as soil survey sample number S86OR-037-001 (pedon # 86P0987). Another pedon from Harney County, OR is reference sampled as soil survey sample number S93OR-025-009 (pedon # 97P0019).