LOCATION WEBFOOT OREstablished Series
TAXONOMIC CLASS: Loamy-skeletal, mixed, superactive, frigid Pachic Haploxerolls
TYPICAL PEDON: Webfoot silt loam - on a 2 percent slope, woodland. (Colors are for moist soil unless otherwise noted.)
Oi--0 to 2 inches; partially decomposed pine needles, grass, leaves and twigs.
A1--2 to 8 inches; very dark brown (10YR 2/2) silt loam, grayish brown (10YR 5/2) dry; moderate very fine and fine subangular blocky structure; slightly hard, friable, slightly sticky and slightly plastic; many very fine and fine and few medium and coarse roots; many very fine tubular pores; 10 percent gravel; slightly alkaline (pH 7.6); clear smooth boundary. (5 to 10 inches thick)
A2--8 to 15 inches; very dark grayish brown (10YR 3/2) gravelly loam, grayish brown (10YR 5/2) dry; common medium distinct yellowish brown (10YR 5/4) redox concentrations; moderate fine and medium subangular blocky structure; slightly hard, friable, slightly sticky and slightly plastic; many very fine and fine and few medium and coarse roots; many very fine tubular pores; 15 percent gravel; moderately alkaline (pH 8.2); clear smooth boundary. (6 to 12 inches thick)
Bw--15 to 27 inches; very dark grayish brown (10YR 3/2) gravelly sandy loam, grayish brown (10YR 5/2) dry; common medium distinct yellowish brown (10YR 5/4) redox concentrations; moderate fine and medium subangular blocky structure; slightly hard, friable, slightly sticky and slightly plastic; many very fine and fine and few medium and coarse roots; many very fine and fine tubular pores; 20 percent gravel and 5 percent cobbles; slightly alkaline (pH 7.6); gradual smooth boundary. (9 to 18 inches thick)
2Cg1--27 to 37 inches; olive gray (5Y 4/2) very gravelly sandy loam, light olive gray (5Y 6/2) dry; many coarse distinct yellowish brown (10YR 5/6) redox concentrations; massive; slightly hard, friable, slightly sticky and slightly plastic; few fine and medium roots; many very fine and fine irregular pores; 30 percent gravel and 10 percent cobbles; slightly alkaline (pH 7.4); gradual smooth boundary. (10 to 15 inches thick)
2Cg2--37 to 50 inches; dark gray (5Y 4/1) extremely gravelly loamy sand, light gray (5Y 7/1) dry; many coarse distinct yellowish brown (10YR 5/6) redox concentrations; single grain; loose, nonsticky and nonplastic; few fine and medium roots; many very fine and fine irregular pores; 55 percent gravel and 10 percent cobbles; neutral (pH 7.2); gradual smooth boundary. (5 to 15 inches thick)
2Cg3--50 to 60 inches; multicolored extremely gravelly sand; single grain; loose, nonsticky and nonplastic.
TYPE LOCATION: Baker County, Oregon; SE1/4NW1/4SW1/4 of sec. 16, T. 10 S., R. 38 E.
RANGE IN CHARACTERISTICS: The mean annual soil temperature ranges from 42 to 47 degrees F, and the mean summer temperature is greater than 55 degrees F. The soil is saturated from March through June at a depth of 1.0 to 2.0 feet; it is dry in all parts of the moisture control section from mid-July through mid-September. The mollic epipedon and depth to the 2Cg horizon is 20 to 40 inches. The particle-size control section averages 5 to 15 percent clay and 35 to 60 percent coarse fragments.
The A horizon has value of 2 or 3 moist, 4 or 5 dry and chroma of 1 or 2 moist and dry. It has 0 to 15 percent gravel, and some pedons may have up to 15 percent (2-4 mm) concretions. The lower part of this horizon has few to common distinct mottles. It is slightly or moderately alkaline. It has 4 to 10 percent organic matter.
The Bw horizon has hue of 10YR or 2.5Y, value of 2 or 3 moist, 4 or 5 dry and chroma of 0 to 2 moist and dry. It is gravelly sandy loam or gravelly loam with 10 to 20 percent gravel and 0 to 5 percent cobbles. It has few to many distinct or prominent mottles. It is slightly or moderately alkaline.
The 2Cg horizon has hue of 5Y or 2.5Y and is usually gleyed. It has value of 4 or 5 moist, 6 or 7 dry and chroma of 0 to 2 moist and dry. It is extremely gravelly loamy sand, extremely gravelly sand or very gravelly sandy loam with 30
to 60 percent gravel and 10 to 20 percent cobbles. It is neutral or slightly alkaline.
COMPETING SERIES: These are the
Baldridge,
Burgi,
Chambeam,
Climine,
Fredonyer,
Ginser,
Glean,
Lambring,
Rondowa,
Sinker,
Smidale,
St. Anthony,
Westbutte, and
Willynat series. All of these soils lack the saturated layer above 40 inches for 90 or more consecutive days. Burgi, Climine, and St. Anthony soils have 18 to 27 percent clay in the particle-size control section. Baldridge soils have a cambic horizon and formed in colluvium derived from rhyolite and andesite. Chambeam soils have a cambic horizon and the coarse fragments are channery. Fredonyer, Ginser, Sinker and Westbutte soils are 20 to 40 inches to bedrock.
Glean soils have 1 to 3 percent organic matter in the mollic epipedon. Lambring soils have 2 to 3 percent organic matter in the mollic epipedon. Smidale soils have a mollic epipedon more than 50 inches thick and have 16 to 30 percent clay in the particle-size control section. Willynat soils have a mollic epipedon 40 to 60 inches thick.
GEOGRAPHIC SETTING: Webfoot soils occur on low terraces. Slopes are 0 to 7 percent. Elevations range from 3,800 to 4,200 feet. The soils formed in mixed alluvium from mixed rock types with an influence of loess and volcanic ash in
the surface horizon. The mean annual precipitation is 16 to 24 inches. The mean annual air temperature is 40 to 45 degrees F. The frost-free period is 50 to 90 days. This soil is on the Winkle geomorphic surface.
GEOGRAPHICALLY ASSOCIATED SOILS: These are McEwen, Stovepipe and Sumpley soils. McEwen soils are on adjacent higher terraces, are well drained, have an argillic horizon and are fine-loamy. Stovepipe and Sumpley soils are on adjacent flood plains. Stovepipe soils are poorly drained, coarse-silty over sandy or sandy-skeletal and are cryic. Sumpley soils are fine-loamy over sandy or sandy-skeletal.
DRAINAGE AND PERMEABILITY: Somewhat poorly drained. Runoff is slow. Permeability is moderately in the surface layer and rapid in the substratum. A water table fluctuates between 12 and 24 inches from March through June and the
soil is subject to rare flooding.
USE AND VEGETATION: Most areas of Webfoot soils are used for timber production. In some areas the trees have been cleared and the soils are used for hay and pasture. The vegetation is ponderosa pine, common snowberry, spirea, willow, rose, serviceberry, elk sedge and wild strawberry.
DISTRIBUTION AND EXTENT: Higher elevation valleys and basins of eastern Oregon. The series is of small extent.
MLRA SOIL SURVEY REGIONAL OFFICE (MO) RESPONSIBLE: Bozeman, Montana
SERIES ESTABLISHED: Baker County Area, Oregon, 1988.
REMARKS: Diagnostic horizons and features in this pedon are:
Mollic epipedon (Pachic) - the zone from the surface of the soil to a depth of approximately 27 inches (A1, A2, Bw horizons).
Aquic feature - profile has distinct redox features at 8 inches and the soil is saturated at 1.0 to 2.0 feet from March through June. The soil water contains dissolved oxygen because of lateral movement.