LOCATION OXMAN OR

Established Series
Rev. WEL/TDT
01/2023

OXMAN SERIES

The Oxman series consists of moderately deep, well drained soils on dissected fan terraces. They formed in lacustrine sediments. Slopes are 2 to 35 percent. The mean annual precipitation is about 10 inches and the mean annual temperature is about 48 degrees F.

TAXONOMIC CLASS: Fine-loamy, mixed, superactive, mesic Xeric Haplocambids

TYPICAL PEDON: Oxman silt loam, rangeland. (Colors are for dry soil unless otherwise noted.)

A--0 to 4 inches; pale brown (10YR 6/3) silt loam, dark brown (10YR 3/3) moist; moderate fine and medium granular structure parting to weak very thin platy; soft, very friable, slightly plastic and slightly sticky; many very fine roots; many very fine tubular and irregular pores; strongly effervescent; moderately alkaline (pH 8.0); abrupt wavy boundary. (3 to 6 inches thick)

Bk--4 to 11 inches; pale brown (10YR 6/3) silt loam, brown (10YR 4/3) moist; moderate coarse subangular blocky structure; slightly hard, friable, slightly sticky and slightly plastic; common very fine roots; many very fine tubular pores; slightly effervescent; slightly alkaline (pH 7.8); abrupt wavy boundary. (5 to 10 inches thick)

2Bk1--11 to 21 inches; very pale brown (10YR 7/3) silt loam, brown (10YR 4/3) moist; moderate coarse subangular blocky structure; slightly hard, friable, nonsticky and nonplastic; few very fine roots; common very fine tubular pores; violently effervescent; moderately alkaline (pH 8.2); gradual wavy boundary. (7 to 15 inches thick)

2Bk2--21 to 29 inches; very pale brown (10YR 7/3) silt loam, dark yellowish brown (10YR 4/4) moist; moderate medium and coarse subangular blocky structure; slightly hard, friable, nonsticky and nonplastic; few very fine roots; few very fine tubular pores; about 20 percent soft gravel size lacustrine sediment fragments; violently effervescent; moderately alkaline (pH 8.0). (5 to 10 inches thick)

2Cr--29 inches; light gray (10YR 7/1) platy lacustrine sediment; can be dug with a spade but with difficulty.

TYPE LOCATION: Baker County, Oregon; about 1 mile southeast of Durkee, in the SW1/4NE1/4 sec. 28, T. 11 S., R. 43 E.

RANGE IN CHARACTERISTICS: These soils are usually dry; moist winter and spring, dry mid June through early October. The mean annual soil temperature is about 47 to 52 degrees F. Depth to consolidated lacustrine sediments and solum thickness is 20 to 40 inches. The particle-size control section has an average of 18 to 35 percent clay and 15 to 25 coarser than very fine sand.

The A horizon has value of 5 or 6 dry and 3 or 4 moist, and chroma of 2 or 3 moist and dry.

The Bk horizon has moist value of 3 or 4 and chroma of 2 to 4 moist. It is silt loam or silty clay loam with 18 to 35 percent clay.

The 2Bk horizons have value of 6 or 7 dry and 4 or 5 moist, and chroma of 3 to 6 dry and 3 or 4 moist. It is silt loam, very fine sandy loam, or silt loam with 15 to 27 percent clay. It is mildly alkaline or moderately alkaline. Percent of soft lacustrine fragments is 0 to 25 in the lower part.

COMPETING SERIES: These are the Agency, Defenbaugh(T), Ferdelford, Legler, North Powder, Pocan, Potratz, and Redmond series. Agency, Potratz, and Redmond soils have lithic contacts at 20 to 40 inches. Defenbaugh, Legler and Pocan soils are more than 40 inches deep. Ferdelford soils have a solum 11 to 20 inches thick, lack a lithologic discontinuity and are typically calcareous throughout. North Powder soils are noncalcareous above 18 inches.

GEOGRAPHIC SETTING: Oxman soils are on dissected fan terraces. They formed in lacustrine sediments. Slopes are 2 to 35 percent. Elevation is 2,600 to 3,500 feet. The mean annual precipitation is about 9 to 12 inches, the mean annual temperature is 45 to 50 degrees F, and the frost-free period is 110 to 130 days.

GEOGRAPHICALLY ASSOCIATED SOILS: These are the Poall series and the competing Legler series. Poall soils are deep, have a clay subsoil, and occur on adjacent higher terraces.

DRAINAGE AND PERMEABILITY: Well drained; slow to medium runoff; moderate permeability.

USE AND VEGETATION: Used for range and wildlife habitat. The native vegetation is bluebunch wheatgrass, Thurber needlegrass, Sandberg bluegrass, Wyoming big sagebrush, and wild crab apple.

DISTRIBUTION AND EXTENT: Eastern Oregon. The soils are inextensive.

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

SERIES ESTABLISHED: Baker County Area, Oregon; 1988.

REMARKS: Diagnostic horizons and features in this pedon are:

Ochric epipedon - dry value of 6 throughout the upper 11 inches and moist value of 4 from 4 to 11 inches.

Cambic horizon - the zone from 4 to 29 inches secondary carbonate - violently effervescent from 11 to 29 inches (Bk1 and Bk2 horizons).

Paralithic contact at 29 inches.

NSTH 17, RECLASSIFICATION ONLY, 3/95

National Cooperative Soil Survey
U.S.A.