LOCATION WANNACOTT WAEstablished Series
TAXONOMIC CLASS: Fine-silty, mixed, superactive, mesic Calcic Argixerolls
TYPICAL PEDON: Wannacott silt loam-on a 6 percent north facing slope under grass and shrubs at an elevation of 2,430 feet. (Colors are for dry soil unless otherwise stated.)
A--0 to 10 inches; grayish brown (10YR 5/2) silt loam, very dark grayish brown (10YR 3/2) moist; weak very fine subangular blocky structure; soft, very friable, slightly sticky and slightly plastic; many very fine and fine roots; 3 percent pebbles; neutral; (pH 6.8); clear smooth boundary. (7 to 12 inches thick)
BA--10 to 15 inches; light yellowish brown (10YR 6/4) silt loam, brown (10YR 4/3) moist; weak fine subangular blocky structure; slightly hard, friable, slightly sticky and slightly plastic; many very fine and common fine roots; 3 percent pebbles; neutral (pH 6.8); clear smooth boundary. (0 to 6 inches thick)
Bt--15 to 22 inches; light brownish gray (2.5Y 6/2) silt loam, olive brown (2.5Y 4/4) moist; moderate fine subangular blocky structure; hard, firm, sticky and plastic; few thin clay films in pores and on ped faces; common very fine and fine roots; 3 percent pebbles; moderately alkaline (pH 8.2); abrupt smooth boundary. (5 to 10 inches thick)
Btk--22 to 29 inches; light yellowish brown (2.5Y 6/4) silty clay loam, olive brown (2.5Y 4/4) moist; moderate medium subangular blocky structure; slightly hard, friable, sticky and plastic; common, moderately thick clay films on ped faces and in pores; few fine roots; 5 percent pebbles; common soft powdery calcium carbonate accumulations in cracks and seams; strongly effervescent; strongly alkaline (pH 8.8); abrupt smooth boundary. (5 to 12 inches thick)
2C--29 to 35 inches; light brownish gray (2.5Y 6/2) gravelly sandy loam, olive brown (2.5Y 4/4) moist; massive; hard, friable, slightly sticky and slightly plastic; few fine roots; 20 percent pebbles; slightly effervescent; strongly alkaline (pH 8.8); clear smooth boundary. (5 to 13 inches thick)
2Cd--35 to 60 inches; light gray (2.5Y 7/2) dense glacial till that crushes to gravelly sandy loam, dark grayish brown (2.5Y 4/2) moist; massive; hard, friable, nonsticky and nonplastic; 25 percent pebbles; strongly alkaline (pH 8.6).
TYPE LOCATION: Colville Indian Reservation; Okanogan County, Washington; about 8 miles west of the town of Disautel; 600 feet west and 900 feet south of the northeast corner of sec. 17, T. 33 N., R. 28 E., W.M.
RANGE IN CHARACTERISTICS: The mean annual soil temperature at a depth of 20 inches is 49 to 51 degrees F. These soils are usually moist but are dry in all parts between depths of 4 to 12 inches for 90 to 105 consecutive days following the summer solstice. The mollic epipedon is 7 to 14 inches thick. Depth to the Btk horizon ranges from 12 to 25 inches. The particle-size control averages 18 to 35 percent clay and is less than 15 percent fine sand or coarser material. Depth to densic material is 20 to 40 inches.
The A horizon has value of 4 or 5 dry, 2 or 3 moist, and chroma of 2 or 3 dry or moist. It is 0 to 10 percent coarse fragments. Reaction is neutral or mildly alkaline.
The BA horizon has value of 6 or 7 dry, 4 or 5 moist, and chroma of 3 or 4 moist or dry. It is 0 to 10 percent pebbles. Reaction is neutral or mildly alkaline.
The Bt horizon has hue of 10YR or 2.5Y, value of 6 or 7 dry, 4 or 5 moist, and chroma of 2 through 4 moist or dry. It is silt loam or silty clay loam and is 0 to 10 percent pebbles. Reaction ranges from mildly alkaline to moderately alkaline. There are few to common thin to moderately thick clay films.
The Btk horizon has hue of 10YR or 2.5Y, value of 6 or 7 dry, 4 or 5 moist, and chroma of 2 through 4 dry or moist. It is silt loam or silty clay loam and is 0 to 10 percent pebbles. There are common, thin to moderately thick clay films on faces of peds. Reaction is mildly alkaline to strongly alkaline.
The 2C horizon has value of 6 or 7 dry, 4 or 5 moist, and chroma of 2 through 4 dry or moist. It is 8 to 18 percent clay and 15 to 35 percent pebbles in the upper part and 15 to 50 percent in the lower part. Reaction is mildly alkaline or moderately alkaline.
COMPETING SERIES: These are the Broadax, McKay, Morrow, Nephi, and Parleys series. Broadax soils have no rock fragments throughout the profile. McKay soils are dry for 60 to 90 consecutive days and are more than 18 percent clay below Bt horizon. McKay soils lack dense glacial till in the lower part of the particle-size control section. Morrow soils have a lithic contact at a depth of 20 to 40 inches. Nephi soils have 5YR hue in the Bt horizon. Parleys soils have a calcic horizon and a Bt horizon which is neutral or slightly acid.
GEOGRAPHIC SETTING: Wannacott soils are on glaciolacustrine influenced moraines. These soils formed in intermixed glaciolacustrine sediments and glacial till with a component of loess in the upper part. Slopes are 0 to 15 percent. Elevations range from 2,200 to 2,700 feet. The climate is characterized by warm, dry summers and cool, moist winters. The average annual precipitation is 12 to 15 inches. The mean January temperature is about 24 degrees F. and mean July temperature is about 70 degrees F. The frost-free season is 110 to 150 days.
GEOGRAPHICALLY ASSOCIATED SOILS: These are the Conconully, Disautel, and Nespelem soils. Conconully soils have a cambic horizon, lack secondary carbonates within the control section, and are coarse-loamy. Disautel soils have a cambic horizon and are coarse-loamy. Nespelem soils have a thin duripan at a depth of 20 to 40 inches, have a cambic horizon, and are coarse-silty.
DRAINAGE AND PERMEABILITY: Well drained, slow to medium runoff; permeability is moderately slow in the argillic horizon and slow through the dense till.
USE AND VEGETATION: Livestock grazing, dryland cultivated crops, hay and Pasture, watershed, and wildlife habitat are the principle uses. Small grains, grasses and alfalfa are common crops. The native vegetation is bluebunch wheatgrass, Idaho fescue, Sandberg bluegrass, Wyeth eriogonum, silky lupine, common yarrow, micro pussytoes, Thompson Indian paintbrush, showy phlox, and threetip sagebrush.
DISTRIBUTION AND EXTENT: Northcentral Washington. The series is of small extent.
MLRA SOIL SURVEY REGIONAL OFFICE (MO) RESPONSIBLE: Portland, Oregon
SERIES ESTABLISHED: Colville Indian Reservation; Okanogan County, Washington, 1987.
REMARKS: Diagnostic horizons and features recognized in this soil are a mollic epipedon from the surface to 10 inches, an argillic horizon from 15 to 29 inches, and secondary carbonates from a depth of 22 to 60 inches.