LOCATION PYWELL ID+WA

Established Series
Rev. SMM-SHB-RJS
04/2017

PYWELL SERIES

The Pywell series consists of very deep, very poorly drained organic soils in depressional areas of bottomlands, drainageways and flood plains. They formed in material derived dominantly from herbaceous plants, but including some woody materials. Saturated hydraulic conductivity is moderately high. Slopes are 0 to 3 percent. Average annual precipitation is about 625 mm, and the average annual air temperature is about 7.2 degrees C.

TAXONOMIC CLASS: Euic, frigid Typic Haplosaprists

TYPICAL PEDON: Pywell muck, in a nearly level pasture; on a 0 percent slope at 540 meters elevation. When described on November 13, 1972, the soil was moist to 110 cm and saturated below. (Colors are for moist soil.)

Oap--0 to 25 cm; very dark brown (10YR 2/2) on broken face and rubbed, sapric material; about 15 percent fibers, about 5 percent after rubbing; moderate very fine and fine granular structure; many fine roots; neutral (pH 7.0); abrupt smooth boundary. (0 to 25 cm thick)

Oa1--25 to 36 cm; dark reddish brown (5YR 2/2) on broken face and rubbed, sapric material; about 25 percent fibers, about 5 percent after rubbing; moderate very fine and fine granular structure; many fine roots; neutral (pH 6.7); abrupt wavy boundary. (8 to 25 cm thick)

Oa2--36 to 56 cm; very dark gray (10YR 3/1) on broken face and rubbed, sapric material; about 25 percent fibers, less than 5 percent after rubbing; massive; few fine roots; 0.6 cm discontinuous layer of volcanic ash; neutral (pH 6.6); abrupt wavy boundary. (18 to 36 cm thick)

Oa3--56 to 84 cm; very dark brown (10YR 2/2) on broken face and rubbed, sapric material; about 20 percent fibers, less than 5 percent after rubbing; massive; 0.6 cm discontinuous layer of volcanic ash; slightly acid (pH 6.4); abrupt wavy boundary. (0 to 36 cm thick)

Oa4--84 to 178 cm; very dark gray (10YR 3/1) on broken face and rubbed, sapric material; about 25 percent fibers, less than 5 percent after rubbing; massive; 0.6 cm discontinuous layer of volcanic ash; slightly acid (pH 6.3).

TYPE LOCATION: Boundary County, Idaho; south end of Drainage District No. 15; about 30 meters south of power pole B596; about 610 meters north and 400 meters east of the southwest corner, sec. 32, T. 62 N., R. 2 E.; Latitude - 48 degrees, 40 minutes, 45 seconds North; Longitude - 116 degrees, 14 minutes, 13 seconds West; USGS Moyie Springs Quadrangle.

RANGE IN CHARACTERISTICS:
Average annual soil temperature -- 6.1 to 7.8 degrees C.
Depth to high water table -- 28 to 90 cm (January to December) drained, 0 to 28 cm (December to July) undrained.
Organic layers -- more than 75 cm thick mostly sapric, but some pedons have variable amounts of fibric or hemic material
Volcanic ash -- thin, discontinuous layers present in some pedons (0.5 to 8 cm thick)
Woody material -- 0 to 35 percent, present in the lower part of some pedons
Reaction -- neutral to very strongly acid throughout

Surface tier
Hue: 10YR, 7.5YR, 5YR or neutral
Value: 2 to 4 moist
Chroma: 0 to 3 moist, chroma and value may change 1 unit when pressed and rubbed

Subsurface tier
Hue: 10YR, 7.5YR, 5YR, 2.5Y or neutral
Value: 2 to 5 moist
Chroma: 0 to 4 moist

Bottom tier
Hue: 5Y to 5YR
Value: 2 to 5 moist
Chroma: 0 to 4 moist

COMPETING SERIES:
Bucksport (ME): have woody fibers throughout the profile
Lupton (MI): slightly alkaline throughout; do not have volcanic ash layers
Seelyeville (MN): soils have hemic material in the control section; do not have volcanic ash layers
Tendoy (ID): are slightly effervescent in the surface tier; do not have volcanic ash layers

GEOGRAPHIC SETTING:
Landforms -- bottomlands, drainageways, flood plains
Elevations -- 525 to 925 meters
Slopes -- 0 to 3 percent
Parent material -- organic material derived dominantly from herbaceous plants and including some woody materials
Mean annual precipitation - 500 to 900 mm
Mean annual air temperature -- 5.6 to 7.8 degrees C.
Frost-free season -- 80 to 125 days

GEOGRAPHICALLY ASSOCIATED SOILS: These are the Capehorn, DeVoignes, Hoodoo, Odenson, Ritz, and Schnoorson soils. Capehorn, Hoodoo, Odenson, Ritz, and Schnoorson soils are on flood plains and are mineral soils. DeVoignes soils are on flood plains and have stratified organic material and mineral material and average fine-silty family in the control section.

DRAINAGE AND SATURATED HYDRAULIC CONDUCTIVITY: Very poorly drained; moderately high saturated hydraulic conductivity. These soils are frequently flooded from December through June for very long periods unless protected by levees. Most areas have been drained and protected from flooding for farming. Ponding occurs in areas that are not drained or protected from flooding

USE AND VEGETATION: Most Pywell soils have been cleared, diked, and drained for farming. They are used primarily for production of spring wheat, oats, barley, grass seed, hay, and pasture. Some areas are used for wetland wildlife habitat. Natural vegetation is willow, black cottonwood, thinleaf alder, pyramid spirea, narrowleaf cattail, reed canary grass, sedge, and rush with scattered western redcedar and Englemann spruce along edges of meadows.

DISTRIBUTION AND EXTENT: Northern Idaho, northeastern Washington, and possibly northwestern Montana. The series is moderately extensive. MLRAs 9 and 44A.

MLRA SOIL SURVEY REGIONAL OFFICE (MO) RESPONSIBLE: Bozeman, Montana

SERIES ESTABLISHED: Boundary County, Idaho, 1974.

REMARKS: Diagnostic horizons and features recognized in this pedon are:
Organic soil material (Sapric) -- the zone from 0 to 178 cm (Oap, Oa1, Oa2, Oa3, Oa4 horizons)
Histosol control section -- the zone from 0 to 130 cm (Oap, Oa1, Oa2, Oa3, part of the Oa4 horizon)

ADDITIONAL DATA: Laboratory data available for Soil Survey Sample Number: 78ID017012, Bonner County, Idaho. KSSL Pedon Number: 78P0557.

Taxonomic version: Keys to Soil Taxonomy, Twelfth Edition, 2014.

National Cooperative Soil Survey
U.S.A.