LOCATION BECA WAEstablished Series
TAXONOMIC CLASS: Coarse-loamy, mixed, superactive, mesic Vitrandic Argixerolls
TYPICAL PEDON: Beca ashy fine sandy loam - cropland, wheat stubble, on a 10 percent north-northeast facing slope at an elevation of 2,990 feet. (Colors are for dry soil unless otherwise stated. All textures are apparent field textures and spot plate reaction is used for pH values.)
Ap--0 to 8 inches; grayish brown (10YR 5/2) ashy fine sandy loam, very dark grayish brown (10YR 3/2) moist; moderate medium and fine subangular structure; slightly hard, very friable, nonsticky and nonplastic; many very fine and common fine roots; few very fine tubular and common very fine irregular pores; 10 percent sand-size pumice, 0.5 to 2.0 mm. in diameter; slightly acid (pH 6.5); abrupt smooth boundary. (7 to 8 inches thick)
A--8 to 14 inches; grayish brown (10YR 5/2) ashy fine sandy loam, very dark grayish brown (10YR 3/2) moist; weak coarse subangular blocky structure parting to weak medium and fine subangular blocky; slightly hard, friable, nonsticky and slightly plastic; many very fine roots; common very fine and few tubular pores and common very fine irregular pores; 15 percent sand-size pumice, 0.5 to 2.0 mm. in diameter; neutral (pH 7.0); clear smooth boundary. (7 to 8 inches thick)
BA--14 to 23 inches; brown (10YR 5/3) ashy fine sandy loam, dark brown (10YR 3/3) moist; weak coarse prismatic structure parting to weak coarse and medium subangular blocky; slightly hard, friable, nonsticky and slightly plastic; common very fine roots; common very fine and few fine tubular and common very fine and few fine irregular pores; 25 percent sand-size pumice, 0.5 to 2.0 mm. in diameter; neutral (pH 7.2); clear wavy boundary. (6 to 9 inches thick)
2Bt1--23 to 31 inches; brown (10YR 5/3) silt loam, dark brown (10YR 3/3) moist; moderate medium prismatic structure parting to moderate medium subangular; slightly hard, friable, slightly sticky and slightly plastic; common very fine roots; many very fine and few fine tubular and few very fine and fine irregular pores; few faint clay bridges between sand grains on faces of peds; common faint stress surfaces on faces of peds; 5 percent sand-size pumice, 0.5 to 2.0 mm. in diameter; 5 percent basalt pebbles; neutral (pH 7.2); abrupt wavy boundary. (3 to 8 inches thick)
2Bt2--31 to 38 inches; yellowish brown (10YR 5/4) gravelly silt loam, dark grayish brown (10YR 4/2) moist; strong coarse and medium subangular blocky structure; slightly hard, friable, slightly sticky and slightly plastic; common very fine roots; common very fine and fine tubular and common very fine and few fine irregular pores; few faint clay films on faces of peds and in pores; few clay bridges between sand grains on faces of peds; common distinct stress surfaces on faces of peds; 1 percent sand-size pumice, 0.5 to 2.0 mm. in diameter; 20 percent basalt pebbles and 5 percent basalt cobbles; few distinct white (10YR 8/1) silica coatings and common distinct strong brown (7.5YR 5/6), moist, clay films on coarse fragment surfaces; neutral (pH 7.2); abrupt wavy boundary. (0 to 8 inches thick)
3R--38 inches; basalt.
TYPE LOCATION: Douglas County, Washington; approximately 4 miles north of Waterville; about 2,300 feet south and 20 feet east of the northwest corner of section 33, T. 26 N., R. 22 E. (Latitude 47 degrees 42 minutes 30 seconds N, Longitude 120 degrees 05 minutes 30 seconds
W)
RANGE IN CHARACTERISTICS: The mean annual soil temperature is 49 to 51 degrees F. These soils are usually moist in the moisture control section but are dry for 90 to 105 consecutive days following the summer solstice. The mollic epipedon is 20 to 25 inches thick and has an estimated moist bulk density of 1.10 to 1.35 g/cc, volcanic glass content of 30 to 60 percent, including 15 to 30 percent sand-size pumice, 0.5 to 2.0 mm. in diameter, acid-oxalate extractable aluminum plus one-half of the acid-oxalate extractable iron of 0.15 to 0.40 percent, 15-bar water retention of 5 to 10 percent, 0 to 5 percent basalt rock fragments, and an apparent field estimated clay content of 5 to 14 percent.
The particle-size control section has 10 to 18 percent clay, 1 to 8 percent sand-size pumice, 0.5 to 2.0 mm. in diameter, less than 15 percent volcanic glass, 15 percent or more fine sand or coarser, and 10 to 25 percent basalt rock fragments. Depth to basalt is 20 to 40 inches.
The Ap horizon value is 4 or 5 dry and 2 or 3 moist. The chroma is 2 or 3 dry and 1 or 2 moist.
The A and BA horizons have chroma of 2 or 3 dry. Texture is ashy fine sandy loam, ashy silt loam or ashy loam. Reaction is slightly acid or neutral.
The 2Bt1 horizon value is 4 or 5 dry and 3 or 4 moist. The chroma is 3 or 4 dry or moist. The texture is silt loam or loam. There is 5 to 15 percent basalt rock fragments in this horizon. Reaction is neutral or slightly alkaline.
The 2Bt2 horizon value is 4 of 5 dry and 3 or 4 moist. The chroma is 3 or 4 dry or moist. The texture is gravelly silt loam, cobbly silt loam, gravelly loam, or cobbly loam. There is 15 to 35 percent basalt rock fragments in this horizon. Reaction is neutral or slightly alkaline.
COMPETING SERIES: This is the Jordy series. Jordy soils have a mollic epipedon 10 to 18 inches thick.
GEOGRAPHIC SETTING: Beca soils are on flat or dissected hill slopes on uplands. Elevation is 2,400 to 3,200 feet. Slopes are 3 to 40 percent. Beca soils formed in post-Wisconsin loess mixed with volcanic ash and pumice primarily from the G and B eruptions of Glacier Peak 12,750 to 11,250 years ago over Wisconsin and pre-Wisconsin age loess mixed with colluvium over basalt bedrock. The climate is characterized by warm, dry summers and cool, moist winters. Average annual precipitation is 12 to 15 inches. Average January air temperature is 26 degrees F., average July air temperature is 70 degrees F., and average annual air temperature is 47 to 49 degrees F. Frost-free season is 110 to 165 days.
GEOGRAPHICALLY ASSOCIATED SOILS: These are the Dougville, Dutchenry, Norax, and Slickear soils. Dougville soils are on uplands, are coarse-silty and are not underlain by basalt bedrock at 23 to 40 inches depth. Dutchenry soils are on uplands and are moderately deep to thick indurated duripan. Norax soils are on uplands, are fine-silty and do not have a mollic epipedon. Slickear soils are on uplands and are fine-silty.
DRAINAGE AND PERMEABILITY: Well drained; slow to medium runoff; moderate permeability.
USE AND VEGETATION: Beca soils are primarily used for wheat and barley production. Small areas are used for livestock grazing or wildlife habitat. The potential native vegetation is bluebunch wheatgrass, Idaho fescue and threetip sagebrush.
DISTRIBUTION AND EXTENT: North Central Washington. The series is of small extent.
MLRA SOIL SURVEY REGIONAL OFFICE (MO) RESPONSIBLE: Portland, Oregon
SERIES ESTABLISHED: Douglas County, Washington, 1998.
REMARKS: Diagnostic features and horizons recognized in this pedon are a mollic epipedon from 0 to 23 inches, a coarse-loamy argillic horizon from 23 to 38 inches over basalt bedrock. The control section is the zone from 23 to 38 inches (the 2Bt1 and 2Bt2 horizons). The sand-size pumice is white, gray, or yellowish brown and is estimated by percent volume in the soil profile.