LOCATION MANSONIA WAEstablished Series
TAXONOMIC CLASS: Ashy, glassy, mesic Vitrandic Haploxerolls
TYPICAL PEDON: Mansonia cindery fine sandy loam - grassland on a 15 percent east facing slope at an elevation of 2,500 feet. (Colors are for dry soil unless otherwise stated. All textures are apparent field textures).
A1--0 to 4 inches; grayish brown (10YR 5/2) cindery fine sandy loam, very dark grayish brown (10YR 3/2) moist; weak medium granular structure; soft, very friable, nonsticky and nonplastic; many fine and very fine roots; many fine tubular pores; 15 percent pumice; neutral (pH 7.2); clear wavy boundary. (2 to 5 inches thick)
A2--4 to 10 inches; brown (10YR 5/3) cindery fine sandy loam, dark brown (10YR 3/3) moist; weak medium granular structure; soft, very friable, nonsticky and nonplastic; many fine and very fine roots; many fine tubular pores; 15 percent pumice; neutral (pH 7.2); clear wavy boundary. (5 to 7 inches thick)
Bw--10 to 20 inches; light brownish gray (10YR 6/2) cindery sandy loam, yellowish brown (10YR 5/4) moist; weak medium subangular blocky structure; soft, very friable, nonsticky and nonplastic; common fine roots; common fine tubular pores; 20 percent pumice; neutral (pH 7.0); gradual wavy boundary. (8 to 12 inches thick)
C--20 to 50 inches; pale brown (10YR 6/3) cindery sandy loam, single grain; soft, very friable, nonsticky and nonplastic; few fine roots; common fine tubular pores; 5 percent pebbles and 30 percent pumice; neutral (pH 7.0); abrupt wavy boundary. (24 to 36 inches thick)
2R--50 inches; hard granodiorite.
TYPE LOCATION: Chelan County, Washington; about 6 miles northwest of Manson, Washington; 2,000 feet west and 1,750 feet north of southeast corner of sec. 26, T. 29 N., R. 21 E.
RANGE IN CHARACTERISTICS: The mean annual soil temperature is estimated to range from 49 to 51 degrees F. These soils are usually moist, but are dry in the moisture control section for 90 to 105 consecutive days following summer solstice. The 10 to 40 inch particle-size control section has an estimated moist bulk density of 0.55 to 0.85 g/cc, volcanic glass content of 30 to 60 percent, 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 12 percent, and 5 to 35 percent pumice 2.0 to 5.0 mm in diameter. Hard rock fragments range from 0 to 10 percent. Depth to bedrock or dense glacial till is 40 to 60 inches. The mollic epipedon is 7 to 12 inches thick. Reaction is neutral to slightly alkaline.
The A horizon has value of 2 or 3 moist and chroma of 2 or 3 dry and moist.
The Bw horizon has value of 5 or 6 dry and 3 to 5 moist and chroma of 2 to 4 dry and moist. Texture is cindery sandy loam or cindery fine sandy loam.
The C horizon has value of 4 or 5 moist and chroma of 3 or 4 dry and moist. Texture is cindery sandy loam or cindery fine sandy loam.
Some pedons have a very cobbly loamy sand glacial till 2C horizon at 40 to 60 inches. Hue is 10YR or 2.5Y, value is 4 or 5 moist, and chroma is 2 to 4 dry and moist. Hard rock fragments range from 35 to 60 percent by volume.
COMPETING SERIES: These are the Achelake, Dinkels, Nemire, Shiva, Watco and Zark series. The Achelake, Nemire and Shiva soils are over 60 inches deep. Dinkels soils have a mollic epipedon 14 to 20 inches thick. Nemire soils have a mollic epipedon over 20 inches thick. Watco soils are dry for 75 to 90 consecutive days. Zark soils are 20 to 40 inches to a paralithic contact.
GEOGRAPHIC SETTING: Mansonia soils are on foothills on all aspects. Slopes are 3 to 65 percent. Elevation is 1,100 to 3,200 feet. These soils formed in volcanic ash and pumice overlying granodiorite or glacial till. 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 25 degrees F, the mean July temperature is about 70 degrees F, and the mean annual temperature is about 47 to 49 degrees F and the frost-free season is 130 to 160 days.
GEOGRAPHICALLY ASSOCIATED SOILS: These are the Brief, Safety, and Thowson soils. Brief and Safety soils lack 60 percent pyroclastics. Thowson soils have an ochric epipedon.
DRAINAGE AND PERMEABILITY: Well drained, slow to rapid runoff; moderate permeability.
USE AND VEGETATION: Rangeland, livestock grazing, wildlife habitat, watershed, and recreation. Native vegetation is bluebunch wheatgrass, Idaho fescue, western yarrow, antelope bitterbrush, and ceanothus.
DISTRIBUTION AND EXTENT: East slopes of the Cascade Mountains in the northern part of Chelan County, Washington. Series is of small extent.
MLRA OFFICE RESPONSIBLE: Portland, Oregon
SERIES ESTABLISHED: Chelan County, Washington, 1995; Cashmere Mountain Soil Survey.
REMARKS: Diagnostic horizons and features recognized in this pedon are a mollic epipedon from the surface to 10 inches, a cambic horizon from 10 to 20 inches. The 10 to 40 inch particle-size control section is formed volcanic ash and pumice, but does not meet andic soil properties in acid-oxalate extractable aluminum plus one-half the iron.