LOCATION CHEVAL OREstablished Series
TAXONOMIC CLASS: Coarse-loamy over sandy or sandy-skeletal, mixed, superactive, frigid Aquic Cumulic Haploxerolls
TYPICAL PEDON: Cheval silt loam - cultivated. (Colors are for moist soil unless otherwise noted.)
Ap--0 to 6 inches; very dark brown (10YR 2/2) silt loam, dark grayish brown (10YR 4/2) dry; moderate fine subangular blocky structure; soft, friable, nonsticky, nonplastic; many fine roots; many irregular pores; strong effervescence; moderately alkaline (pH 8.0); abrupt smooth boundary. (5 to 9 inches thick)
A--6 to 15 inches; very dark gray (10YR 3/1) silt loam, dark gray (10YR 4/1) dry; weak fine granular; soft, friable, nonsticky, nonplastic; common roots; many very fine tubular pores; strong effervescence; moderately alkaline (pH 8.0); clear smooth boundary. (7 to 12 inches thick)
AC--15 to 24 inches; very dark gray (10YR 3/1) loam, gray (10YR 5/1) dry; massive; soft, friable, nonsticky, nonplastic; few fine roots; many very fine tubular pores; strong effervescence; moderately alkaline (pH 8.0; clear smooth boundary. (5 to 15 inches thick)
C1--24 to 31 inches; dark gray (2.5Y 4/1) gravelly loam, gray (2.5Y 5/1) dry; massive; soft, very friable, nonsticky, nonplastic; few fine roots; few irregular pores; 20 percent gravel; few fine faint (10YR 4/4) redox concentrations; strong effervescence; moderately alkaline (pH 8.0; gradual irregular boundary. (3 to 10 inches thick)
2C2--31 to 60 inches; grayish brown (2.5Y 5/2) very gravelly loamy sand, light brownish gray (2.5Y 6/2) single grain; loose, nonsticky, nonplastic; 55 percent gravel; strong effervescence; moderately alkaline (pH 8.0).
TYPE LOCATION: Wallowa County, Oregon; 1550 feet east and 40 feet south of the NW corner of sec. 13, T. 2 S., R. 44 E. (Latitude 45 degrees, 23 minutes, 43 seconds N, Longitude 117 degrees, 15 minutes, 52 seconds W).
RANGE IN CHARACTERISTICS: The mean annual soil temperature is 44 to 47 degrees F. The soils are usually moist but are dry in the moisture control section for 60 to 90 consecutive days during the summer months. Depth to the very gravelly loamy sand horizon is 20 to 36 inches. Thickness of the mollic epipedon is 20 to 30 inches. Depth to redox depletions and faint redox concentrations with chroma of 2 to 4 in 10YR hue is 18 to 30 inches. The soil is calcareous throughout with 1 to 2 percent CaCO3 equivalent.
The A horizon has value of 2 or 3 moist, 4 or 5 dry and chroma of 1 or 2 moist and dry. It is silt loam with 10 to 18 percent clay and 0 to 15 percent gravel.
The AC horizon has value of 3 moist, 4 or 5 dry and chroma of 1 or 2 moist and dry. It is loam or silt loam with 10 to 20 percent clay and 0 to 25 percent gravel.
The C horizon has hue of 2.5Y to 10YR, value of 4 or 5 moist, 5 or 6 dry and chroma of 1 or 2moist and dry. It is silt loam or loam with 10 to 20 percent clay and 0 to 25 percent gravel.
The 2C horizon is loamy sand or sand with 5 to 15 percent clay and 35 to 60 percent gravel.
COMPETING SERIES: There are no competing series.
GEOGRAPHIC SETTING: The Cheval soils are on flood plains. The soils have formed in stratified alluvium weathered from quartz diorite, limestone, basalt, and sedimentary rocks with an influence of alluvial loess and volcanic ash in the epipedon. Slopes are 0 to 2 percent. Elevation is 3400 to 4400 feet. The climate is The climate is characterized by cold wet winters and hot dry summers. The mean annual precipitation is 13 to 17 inches. The mean annual temperature of 42 to 45 degrees F. The frost-free period is 70 to 100 days.
GEOGRAPHICALLY ASSOCIATED SOILS: These are the Josset, Lostine, Redmount, and Sturgill series. Josset soils have redox concentrations at depths greater than 30 inches. Lostine and Redmount soils are well drained, have a regular decrease in organic matter, and lack contrasting textures. Sturgill soils are poorly drained and fine-silty in the control section. Josset and Sturgill soils are on flood plains. Lostine soils are on outwash plains and terraces. Redmount soils are on outwash plains.
DRAINAGE AND PERMEABILITY: Somewhat poorly drained; moderate permeability in the upper coarse-loamy material and very rapid in the sandy-skeletal substratum. A water table fluctuates from 18 to 30 inches from January to June. Occasional and brief flooding from January to June.
USE AND VEGETATION: The soils are used mainly for native pasture; drained and leveled areas produce improved pastures and clover hay. The potential native vegetation is mostly bluegrass, sedges, rushes, and tufted hairgrass.
DISTRIBUTION AND EXTENT: Valleys of northeastern Oregon, MLRA 9. The series is of small extent.
MLRA SOIL SURVEY REGIONAL OFFICE (MO) RESPONSIBLE: Portland, Oregon
SERIES ESTABLISHED: Wallowa County, Oregon, 1998.
REMARKS: Diagnostic horizons and features recognized in this pedon include:
Mollic epipedon - from surface to 24 inches (Ap, A, and AC horizons).
Cumulic feature - mollic epipedon 20 inches or more thick with an inferred irregular decrease in organic carbon based on the nature of the parent material.
Aquic feature - redox depletions and concentrations with chromas of 2 or less from 24 to 31 inches (C1 horizon).
Particle-size control section - from 10 to 40 inches (lower A, AC, C1 and upper 2C2 horizons).