LOCATION GARRISON WA+IDEstablished Series
TAXONOMIC CLASS: Loamy-skeletal, mixed, superactive, mesic Vitrandic Haploxerolls
TYPICAL PEDON: Garrison ashy loam - cultivated. (Colors are for dry soil unless otherwise noted)
Ap--0 to 9 inches; dark grayish brown (10YR 4/2) ashy loam, very dark brown (10YR 2/2) moist; weak fine and medium granular structure; soft, very friable, slightly sticky and slightly plastic; many roots; 10 percent gravel; neutral (pH 7.2); abrupt smooth boundary. (6 to 10 inches thick)
A--9 to 16 inches; dark grayish brown (10YR 4/2) ashy loam, very dark brown (10YR 2/2) moist; weak medium and coarse subangular blocky structure; slightly hard, very friable, slightly sticky and slightly plastic; many roots; common fine pores; 10 percent gravel; neutral (pH 6.8); gradual wavy boundary. (5 to 10 inches thick)
2Bw--16 to 24 inches; brown (10YR 5/3) gravelly loam, dark brown (7.5YR 3/4) moist; weak fine and medium subangular blocky structure; slightly hard, friable, slightly sticky and slightly plastic; common roots; common fine pores; 20 percent gravel; neutral (pH 6.8); diffuse wavy boundary. (6 to 16 inches thick)
2C--24 to 60 inches; brown (10YR 5/3) very gravelly loamy coarse sand, dark brown (7.5YR 3/4) moist; massive; loose; few roots; 50 percent gravel and 10 percent cobbles; slightly alkaline (pH 7.6); gradual wavy boundary. (5 to 10 inches thick)
TYPE LOCATION: Stevens County, Washington; 400 feet north and 1,600 feet west of the southeast corner of section 34, T. 36 N., R. 39 E.
RANGE IN CHARACTERISTICS: Mean annual soil temperature is 47 to 52 degrees F. These soils are usually moist but are dry between depths of 8 and 24 inches for 60 to 90 consecutive days in late summer. Solum thickness and depth to sand, gravel, and cobbles is 24 to 36 inches. The upper 12 to 20 inches has an estimated moist bulk density of 1.15 to 1.35 g/cc, volcanic glass content of 5 to 20 percent, acid-oxalate extractable aluminum plus one-half of the acid-oxalate extractable iron of 0.4 to 1.0 percent, and 15-bar water retention of 5 to 10 percent for air dried samples. Rock fragments in the particle-size control section average 35 to 70 percent. The mollic epipedon is 12 to 20 inches thick. Some pedons have a very stony surface. Depth to secondary carbonates is 44 to more than 60 inches.
The A horizon has value of 4 or 5 dry, 2 or 3 moist, and chroma of 1 to 3 dry or moist. Reaction is moderately acid to neutral.
The 2Bw horizon has value of 4 to 7 dry, 3 to 5 moist, and chroma of 2 to 4 dry or moist. Texture is loam, sandy loam, or coarse sandy loam and is gravelly, very gravelly, extremely gravelly, very cobbly, or extremely cobbly. It has weak or moderate subangular blocky structure. Reaction is slightly acid or neutral.
The 2C horizon has hue of 7.5YR, 10YR, or 2.5Y, value of 5 to 7 dry, 3 to 6 moist, and chroma of 3 to 5 dry or moist. Texture is loamy sand, sand, coarse sand, or loamy coarse sand, or the 2C horizon is stratified sandy loam to coarse sand. It is very gravelly, extremely gravelly, extremely cobbly, or very stony. It is 40 to 85 percent rock fragments including 30 to 75 percent gravel, 5 to 20 percent cobbles, and 0 to 25 percent stones. Reaction is slightly acid to slightly alkaline.
COMPETING SERIES: These are the Borgeau, Eaglespring, Louiecreek, Neviot, Opportunity (T), Schalow, Wagberg and Whitestone series. Borgeau and Louiecreek soils are more than 60 inches deep to sandy-skeletal material. Eaglespring soils average 18 to 25 percent clay in the particle-size control section and are 40 to 60 inches deep to bedrock. Neviot soils are dry for 100 to 120 consecutive days. Opportunity soils are 36 to 60 inches deep to sandy skeletal material. Whitestone soils formed in granitic colluvium and are 40 to more than 60 inches deep to sandy-skeletal material. Wagberg soils are dry for 90 to 105 consecutive days.
GEOGRAPHIC SETTING: Garrison soils are on outwash terraces and terrace escarpments at elevations of 1,400 to 2,800 feet. Slopes are 0 to 90 percent. The soils formed in outwash of mixed mineralogy with component of loess or volcanic ash in the upper part. The climate is characterized by warm, dry summers and cool, moist winters. The mean annual temperature is 49 degrees F. The mean annual precipitation is 15 to 25 inches. The frost-free season is about 120 to 170 days.
GEOGRAPHICALLY ASSOCIATED SOILS: These are the Cedonia, Hallcreek, Hunters, Inchelium, Phoebe, Scala, and Springdale soils. Cedonia soils are fine-silty, lack a mollic epipedon, and are on lake terraces. Hallcreek soils are sandy-skeletal, have a mantle of volcanic ash 7 to 14 inches thick, and are on outwash terraces. Hunters soils are fine-silty and are on terrace risers and treads. Inchelium soils have a mollic epipedon more than 20 inches thick, are coarse-silty, and are on terraces. Phoebe soils are coarse-loamy and are on outwash terraces. Scala soils lack a mollic epipedon, are coarse-loamy, and are on terraces and terrace escarpments. Springdale soils lack a mollic epipedon, are sandy-skeletal, and are on terraces and terrace breaks.
DRAINAGE AND PERMEABILITY: Somewhat excessively drained; moderate permeability above the sandy-skeletal outwash and very rapid with the outwash.
USE AND VEGETATION: These soils are used for irrigated cropland, dryland cropland, urban development, grazing, and timber production. Cultivated areas are used for the production of alfalfa, grass seed, and small grain. The potential natural vegetation is scattered ponderosa pine with an understory of snowbrush ceanothus, common snowberry, Idaho fescue, bluebunch wheatgrass, prairie junegrass, lupine, rose, threadleaf sedge, and phlox.
DISTRIBUTION AND EXTENT: Eastern Washington and northern Idaho. MLRA 43, 44. The series is of moderate extent.
MLRA OFFICE RESPONSIBLE: Bozeman, Montana
SERIES ESTABLISHED: Stevens County, Washington, 1913.
REMARKS: Diagnostic horizons and features recognized in this pedon are:
Mollic epipedon - the zone from 0 to 16 inches (Ap and A horizons)
Cambic horizon - the zone from 16 to 24 inches (2Bw horizon)
Vitrandic feature - the zone from 0 to 16 inches
Particle-size control section - the zone from 10 to 40 inches (part of the A horizon, the
2Bw and part of the 2C horizon) with a weighted average of 39 percent rock fragments.
The boundary transition between the 2Bw and 2C horizon is more than 5 inches and does not meet contrasting family criteria. In addition, the 2Bw horizon contains more than 50 percent fine sand and coarser and therefore does not meet the loamy over sandy or sandy-skeletal contrasting particle-size class.
The discontinuity in the 2Bw represents the limit of the vitrandic feature and the influence of air-fall volcanic ash
This pedon has a classification revision as of 5/00 from loamy-skeletal, mixed, mesic Vitrandic Haploxerolls to loamy-skeletal, mixed, superactive, mesic Vitrandic Haploxerolls based on revisions to Soil Taxonomy.
ADDITIONAL DATA: Partial laboratory data is available for this soil; NSSL pedon numbers 99P331 and 99P332.