LOCATION PELTON             OR
Established Series
Rev. TMP/RWL
03/98

PELTON SERIES


The Pelton series consists of very deep, well drained soils on flood plains. They formed in alluvium derived from mixed sources. Slopes are 0 to 3 percent. The mean annual precipitation is about 10 inches and the mean annual temperature is about 51 degrees F.

TAXONOMIC CLASS: Loamy-skeletal, mixed, superactive, mesic Torrifluventic Haploxerolls

TYPICAL PEDON: Pelton sandy loam - on a nearly level slope, rangeland. (Colors are for moist soil unless otherwise noted.)

A1--0 to 4 inches; very dark gray (10YR 3/1) sandy loam, grayish brown (10YR 5/2) dry; moderate fine and medium platy structure parting to moderate fine and medium granular; soft, friable, nonsticky and nonplastic; many very fine and fine roots; many very fine and fine irregular pores; 5 percent gravel; mildly alkaline (pH 7.4); gradual smooth boundary.

A2--4 to 10 inches; very dark grayish brown (10YR 3/2) gravelly sandy loam, grayish brown (10YR 5/2) dry; weak fine and medium subangular blocky structure; soft, friable, nonsticky and nonplastic; many very fine and fine roots; many very fine and fine tubular pores; 15 percent gravel; mildly alkaline (pH 7.4); abrupt smooth boundary. (Combined thickness of the A horizon is 8 to 20 inches)

2Bw--10 to 18 inches; dark brown (7.5YR 3/2) very gravelly sandy loam, brown (7.5YR 5/3) dry; moderate fine and medium subangular blocky structure; soft, friable, nonsticky and nonplastic; few very fine and fine roots; few very fine and fine tubular pores; 45 percent gravel and 5 percent cobbles; mildly alkaline (pH 7.4); abrupt smooth boundary. (8 to 20 inches thick)

2C1--18 to 37 inches; dark brown (7.5YR 4/2) extremely cobbly sandy clay loam, brown (7.5YR 5/3) dry; massive; hard, firm, slightly sticky and nonplastic; few very fine roots; few very fine tubular pores; 50 percent cobbles and 30 percent gravel; mildly alkaline (pH 7.4); clear smooth boundary.

2C2--37 to 47 inches; dark brown (7.5YR 4/2) extremely cobbly sandy clay loam, brown (7.5YR 5/4) dry; massive; slightly hard, friable, slightly sticky and nonplastic; few very fine roots; few very fine tubular pores; 40 percent cobbles and 30 percent gravel; mildly alkaline (pH 7.4); clear smooth boundary.

2C3--47 to 60 inches; dark brown (7.5YR 4/3) extremely cobbly loamy sand, brown (7.5YR 5/4) dry; single grain; loose, nonsticky and nonplastic; few very fine roots; 40 percent cobbles and 30 percent gravel; neutral (pH 7.2).

TYPE LOCATION: Wasco County, Oregon, about 2000 feet east and 2200 feet north of the SW corner of section 21, T.8 S., R.14 E. (Latitude 44 degrees, 51 minutes, 30 seconds N, Longitude 121 degrees, 3 minutes, 42 seconds W) Warm Springs Indian Reservation.

RANGE OF CHARACTERISTICS: These soils are usually dry and are dry in all parts of the moisture control section more than half the time (cumulative) that the soil temperature at a depth of 20 inches is above 41 degrees F. The mean annual soil temperature is 52 to 54 degrees F. The mollic epipedon is 10 to 20 inches thick. Depth to the discontinuity is 10 to 20 inches. The particle-size control section averages 18 to 25 percent clay, more than 50 percent sand, and 40 to 85 percent rock fragments.

The A1 horizon has value of 2 or 3 moist, 4 or 5 dry and chroma of 1 or 2 moist and dry. It contains 5 to 10 percent gravel and 0 to 5 percent cobbles.

The A2 horizon has value of 2 or 3 moist, 4 or 5 dry and chroma of 1 or 2 moist and dry. It is gravelly sandy loam or sandy loam and contains 10 to 25 percent gravel and 0 to 10 percent cobbles.

The 2Bw horizon has value of 2 or 3 moist, 4 or 5 dry and chroma of 2 or 3 moist and dry. It contains 40 to 50 percent gravel and 5 to 15 percent cobbles.

The 2C horizon has value of 4 or 5 moist, 5 or 6 dry and chroma of 2 through 4 moist and dry. It is sandy clay loam, sandy loam or loamy sand and contains 40 to 50 percent cobbles and 25 to 40 percent gravel.

COMPETING SERIES: These are the Festus (T) and Logy series. Festus soils have a mean annual soil temperature of 47 to 52 degrees F. and less than 18 percent clay in the particle-size control section. Logy soils average 5 to 15 percent clay in the particle-size control section.

GEOGRAPHIC SETTING: Pelton soils are on flood plains. The soil formed alluvium derived from mixed sources. Slopes are 0 to 3 percent. Elevations are 1100 to 1600 feet. The climate is characterized by cool and moist winters and hot and dry summers. The mean annual precipitation is 9 to 12 inches. The mean annual temperature is 50 to 52 degrees F. The frost-free period is 110 to 160 days. Pelton soils are on the high Ingram geomorphic surface.

GEOGRAPHICALLY ASSOCIATED SOILS: These are the Drybed, Simas and Willowdale soils. Drybed soils are on adjacent terraces and fine-loamy. Simas soils are on south facing slopes and fine, montmorillonitic. Willowdale soils occupy the lowest position on the flood plain and are fine-loamy.

DRAINAGE AND PERMEABILITY: Well drained. Permeability is moderate.

USE AND VEGETATION: These soils are used for livestock grazing and wildlife habitat. The native vegetation is basin big sagebrush, bluebunch wheatgrass and willow.

DISTRIBUTION AND EXTENT: North-central Oregon; MLRA 10. The soils of this series are not extensive.

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

SERIES ESTABLISHED: Wasco County (Warm Springs Indian Reservation), Oregon, 1993.

REMARKS: Diagnostic horizons and features recognized in this pedon are:

Mollic epipedon - the zone from the surface to 18 inches (A1, A2, and 2Bw horizons).

Aridic moisture regime with more than 120 dry days.

Fluventic feature - organic carbon content of more than 0.3 percent throughout to a depth of 125 cm from the surface.

ADDITIONAL DATA: Laboratory data is available for this soil. Reference sample S91OR-031-105 from Jefferson County, Oregon, Warm Springs Indian Reservation; NSSL, Lincoln, NE, 5/92.


National Cooperative Soil Survey
U.S.A.