LOCATION PHILBON IDEstablished Series
TAXONOMIC CLASS: Loamy, mixed, euic, mesic Terric Haplosaprists
TYPICAL PEDON: Philbon peat - rushes and sedges. (Colors are for dry soil unless otherwise noted.)
Oi--0 to 2 inches; very dark gray (10YR 3/1) peat, black (10YR 1/1) moist; 65 to 75 percent fibers; neutral (pH 6.6); clear smooth boundary. (1 to 3 inches thick)
Oe--2 to 12 inches; very dark gray (10YR 3/1) mucky peat, black (10YR 1/1) moist; about 70 percent fibers, 20 percent rubbed; many roots; neutral (pH 6.6); clear smooth boundary. (8 to 20 inches thick)
Oa--12 to 22 inches; very dark gray (10YR 3/1) muck, black (10YR 1/1) moist; about 30 percent fibers, 5 percent rubbed; weak medium granular structure; many very fine and fine roots; neutral (pH 6.6); clear smooth boundary. (8 to 25 inches thick)
2Ab1--22 to 26 inches; very dark gray (2.5Y 3/1) mucky silt loam, black (2.5Y 2/1) moist; very few very fine white and yellowish brown mottles; massive; very hard, friable, slightly sticky, slightly plastic; many very fine to medium roots; many very fine and fine tubular pores; low density; neutral (pH 7.0); clear smooth boundary. (2 to 10 inches thick)
2Ab2--26 to 38 inches; very dark gray (2.5Y 3/1) mucky silt loam, black (2.5Y 1/1) moist; few white spots less than 1mm.; massive; extremely hard, friable, slightly sticky, slightly plastic; common very fine and fine roots; many very fine and fine tubular pores; slightly alkaline (pH 7.4); abrupt smooth boundary. (5 to 15 inches thick)
3Cg1--38 to 49 inches; light gray (5Y 7/1) silty clay loam, gray (5Y 5/1) moist; massive; extremely hard, firm, moderately sticky, moderately plastic; common fine and medium roots; few decayed and brown stained dead roots; many very fine and fine tubular pores; moderately alkaline (pH 8.2); clear smooth boundary. (0 to 15 inches thick)
3Cg2--49 to 65 inches; light gray (5Y 6/1) loam, dark gray (5Y 4/1) moist; massive; hard, very friable, nonsticky, nonplastic; common fine and medium roots; many very fine and fine tubular pores; moderately alkaline (pH 8.2). One inch layer of peat at a depth of 57 inches.
TYPE LOCATION: Bannock County, Idaho; 2,000 feet south and 200 feet west of northeast corner of sec. 3, T.5S., R.33E.
RANGE IN CHARACTERISTICS: The mean annual soil temperature ranges from 47 to 58 degrees F. The soils are saturated with water all or most of the year. Depth to mineral soil ranges from 17 to 30 inches. The organic soil horizons are slightly decomposed in the upper part but below a depth of 12 inches the fiber content visible after rubbing is less than 10 percent. These horizons are slightly acid to slightly alkaline and are slightly calcareous in the upper few inches of some pedons. The mineral soil horizons are medium or moderately fine textured. They are neutral to moderately alkaline and are noncalcareous.
COMPETING SERIES: These are the Linwood, Mountainview, Mukilteo, Palms, Peteeneet, Semiahmoo, Shalcar, and Tepete series. Linwood soils have up to 20 percent coarse woody fragments. Mountainview soils have one or more layers of mineral soil interstratified with layers of organic soil. Mukilteo, Peteeneet, and Semiahmoo soils have no mineral layer above a depth of 35 inches. Palms and Shalcar soils lack relatively undecomposed layers in the upper part. Also, Shalcar soils are medium acid to extremely acid. Tepete soils have a mean annual temperature colder than 47 degrees F.
GEOGRAPHIC SETTING: Philbon soils are in level swales or basins in bottomlands and very low terraces. Elevations range from 2,000 to 5,000 feet. The organic soil horizons were formed dominantly from the decomposition of rushes, sedges, cattails, bulrushes, and other water loving herbaceous plants. The mineral soil horizons were formed from mixed alluvium. The climate has 8 to 25 inches of precipitation and a mean freeze-free period of 100 to 160 days.
GEOGRAPHICALLY ASSOCIATED SOILS: These are the Heiseton, Parehat, and Snake soils. These are mineral soils.
DRAINAGE AND PERMEABILITY: Very poorly drained; ponded or very slow runoff; moderate permeability in the organic soil and moderately slow or moderate permeability in the mineral soil layers. The water table is at or within 15 inches of the surface most of the time.
USE AND VEGETATION: Used mostly for wildlife and recreation. The natural vegetation is mainly rushes, sedges, cattails, bulrushes, and other water loving herbaceous plants.
DISTRIBUTION AND EXTENT: Southeastern Idaho. The soils are inextensive.
MLRA SOIL SURVEY REGIONAL OFFICE (MO) RESPONSIBLE: Portland, Oregon
SERIES ESTABLISHED: Bannock County, Idaho, 1913.
REMARKS: Classified formerly as Bog soils.