LOCATION HUDNUT             WA
Established Series
Rev. TAF/SBC/RJE
01/2002

HUDNUT SERIES


The Hudnut series consists of deep, well drained soils formed in granitic ablation till or glacial outwash with loess and volcanic ash in the upper part. Hudnut soils are on till plains, outwash terraces, and terrace escarpments. Slopes are 0 to 40 percent. The average annual precipitation is about 17 inches and the mean annual air temperature is about 47 degrees F.

TAXONOMIC CLASS: Coarse-loamy, mixed, superactive, mesic Vitrandic Haploxerepts

TYPICAL PEDON: Hudnut gravelly sandy loam on a 14 percent south-facing slope at 2,400 feet elevation under a coniferous forest canopy. (Colors are for dry soil unless otherwise noted)

Oi--0 to 1 inch; pine needles, twigs, bark, cones and highly decomposed organic matter; abrupt smooth boundary. (.5 to 2 inches thick)

A--1 to 3 inches; dark grayish brown (10YR 4/2) gravelly sandy loam, very dark brown (10YR 2/2) moist; weak fine subangular blocky structure; soft, very friable, slightly sticky and slightly plastic; common very fine and few medium roots; 15 percent pebbles; neutral (pH 6.8); clear wavy boundary. (1 to 6 inches thick)

Bw--3 to 18 inches; pale brown (10YR 6/3) gravelly sandy loam, brown (10YR 4/3) moist, weak medium subangular blocky structure, soft, very friable, slightly sticky and nonplastic; common very fine, fine, medium and coarse roots; 20 percent pebbles; neutral (pH 7.0); clear wavy boundary. (15 to 32 inches thick)

C1--18 to 51 inches; pale brown (10YR 6/3) gravelly sandy loam, brown (10YR 4/3) moist; massive; soft, very friable, nonsticky and nonplastic; few very fine, common fine and medium roots; 20 percent pebbles and 5 percent cobbles; neutral (pH 7.0); clear wavy boundary. (0 to more than 45 inches thick)

C2--51 to 60 inches; pale brown (10YR 6/3) very gravelly loamy sand, brown (10YR 4/3) moist; massive; soft, very friable, nonsticky and nonplastic; few very fine and fine roots; 30 percent pebbles and 10 percent cobbles; neutral (pH 7.0).

TYPE LOCATION: Colville Indian Reservation, Okanogan County, Washington, about 6 miles northeast of the town of Nespelem; 1,700 feet south and 2,200 feet east of the northwest corner of sec. 4, T. 31 N., R. 30 E.

RANGE IN CHARACTERISTICS: The mean annual soil temperature at a depth of 20 inches depth is 47 to 50 degrees F. These soils are usually moist but are dry in all parts between depths of 8 and 24 inches for 75 to 90 consecutive days following the summer solstice. The upper 7 to 14 inches has an estimated moist bulk density of 1.35 to 1.50 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 12 percent for air dried samples. Solum thickness is 15 to 32 inches. The particle-size control section averages 4 to 12 percent clay , and 15 to 35 percent rock fragments. Depth to sandy textures is 40 to more than 60 inches. Reaction is slightly acid or neutral.

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 15 to 20 percent pebbles and 0 to 5 percent cobbles.

The Bw horizon is gravelly or cobbly and is 15 to 30 percent pebbles and 0 to 15 percent cobbles.

The C1 horizon, when present, has value of 6 through 8 dry, 4 through 6 moist, and chroma of 2 or 3 dry or moist. It is gravelly or cobbly and is 15 to 30 percent pebbles and 0 to 15 percent cobbles.

The C2 horizon, when present, has value of 6 through 8 dry, 4 through 6 moist, and chroma of 2 or 3 dry or moist. It is gravelly, very gravelly, cobbly, or very cobbly and has 15 to 30 percent pebbles and 0 to 25 percent cobbles. Texture of the fine-earth fraction is loamy sand or sand.

COMPETING SERIES: These are the Bestrom, Casselary, Clayton, Green Bluff, Koerling, Koseth, and Scala series. Clayton soils are dry for 60 to 75 consecutive days and has 0 to 5 percent rock fragments throughout the profile. Scala soils have less than 15 percent rock fragments in the particle-size control section.

GEOGRAPHIC SETTING: Hudnut soils are on till plains, glacial outwash terraces, and their escarpments. These soils formed in coarse-textured granitic ablation till and glacial outwash with some loess and volcanic ash in the upper part. Elevation ranges from 1,800 to 2,700 feet. Slopes are 0 to 40 percent. The average annual precipitation ranges from 15 to 18 inches. Summers are warm and dry and winters are cool and moist. The mean July temperature is about 68 degrees F, mean January temperature is about 25 degrees F, and the mean annual temperature is about 47 degrees F. Frost-free season is 100 to 130 days.

GEOGRAPHICALLY ASSOCIATED SOILS: These are the Conconully, Donavan, Republic, and Spens soils. Conconully, Donavan, and Republic soils have mollic epipedons. Spens soils are sandy-skeletal.

DRAINAGE AND PERMEABILITY: Well drained, slow to rapid runoff, moderately rapid permeability. Some pedons have permeability ranging to very rapid below a depth of about 50 inches.

USE AND VEGETATION: Used for timber production, grazing, and wildlife habitat. Native vegetation is ponderosa pine, Saskatoon serviceberry, common chokecherry, wood rose, common snowberry, pinegrass, Idaho fescue, and gland cinquefoil.

DISTRIBUTION AND EXTENT: Northeastern Washington. The series is of small extent.

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

SERIES ESTABLISHED: Colville Indian Reservation, Okanogan County, Washington, 1987.

REMARKS: Diagnostic horizons and features recognized in this pedon are an ochric epipedon from the mineral surface to 2 inches and a cambic horizon from 2 to 17 inches. The description reflects a change in classification from coarse-loamy, mixed, mesic Vitrandic Xerochrepts to coarse-loamy, mixed, superactive, mesic Vitrandic Haploxerepts.


National Cooperative Soil Survey
U.S.A.