LOCATION TERRODD                 OR

Tentative Series
IRD. RAW/DAL
05/2013

TERRODD SERIES

The Terrodd series consists of very deep, somewhat poorly drained soils on low terraces of mountain valley floors. Terrodd soils formed in alluvium from mixed rocks. Slopes are 0 to 5 percent. Mean annual precipitation is about 23 inches and mean annual temperature about 44 degrees F.

TAXONOMIC CLASS: Fine-loamy, mixed, superactive, frigid Aquic Cumulic Hapludolls

TYPICAL PEDON: Terrodd silt loam - under conifer forest, on 0 percent slope at elevation of 3,360 feet. (Colors are for moist soil unless otherwise noted. Soil textures are apparent field textures.)

A1--0 to 11 inches; dark reddish brown (5YR 2.5/2) silt loam, brown (7.5YR 5/2) dry; weak medium and fine granular structure; soft, friable, slightly sticky and slightly plastic; common very fine, fine, medium and few coarse roots throughout; few fine and medium tubular, and few very fine irregular pores; neutral (pH 7.0); clear wavy boundary.

A2--11 to 24 inches; dark brown (7.5YR 3/2) silt loam, brown (7.5YR 5/2) dry; weak medium and fine subangular blocky structure; soft, friable, slightly sticky and slightly plastic; common very fine, fine, medium and few coarse roots throughout; few very fine tubular and irregular pores; slightly alkaline (pH 7.5); clear smooth boundary. (Combined thickness of A horizons is 20 to 30 inches)

2Bw--24 to 43 inches; dark brown (7.5YR 3/2) very stony sandy clay loam, brown (7.5YR 5/3) dry; common medium prominent reddish yellow (7.5YR 6/6) redox concentrations, few medium faint dark grayish brown (10YR 4/2) redox depletions; weak very fine subangular blocky structure; soft, very friable, moderately sticky and moderately plastic; few fine and medium roots throughout; few very fine irregular pores; 25 percent gravel, 15 percent cobbles, and 15 percent stones; slightly alkaline (pH 7.5); gradual smooth boundary. (6 to 30 inches thick)

2C--43 to 61 inches; dark brown (7.5YR 3/2) extremely stony loamy sand, brown (7.5YR 5/3) dry; many fine prominent reddish yellow (7.5YR 6/6) redox concentrations; single grain; loose, nonsticky and nonplastic; common very fine irregular pores; 35 percent gravel, 20 percent cobbles, and 20 percent stones; slightly alkaline (pH 7.5).

TYPE LOCATION: Wallowa County, Oregon
Section 19 (SE , NE , SE ), T. 3 N., R. 45 E.
UTM Coordinates: Zone 11; northing: 5,063,449; easting: 482,169; NAD27
Latitude: 45 43 34.8 N; Longitude: 117 13 44.9 W
USGS Quadrangle: Roberts Butte

RANGE IN CHARACTERISTICS:
Soil Temperature: frigid regime
Mean Annual Soil Temperature: 44 to 47 degrees F
Mean Summer Soil Temperature: 52 to 58 degrees F
Mean Winter Soil Temperature: 34 to 38 degrees F
Soil Moisture: udic regime, dry 25 to 45 days in summer

Particle-size control section: 10 to 40 inches below mineral soil surface
Clay content, weighted average: 24 to 32 percent
Rock fragment content, weighted average: 5 to 30 percent
Upper part (10 to 20 inches thick): 0 to 10 percent
Lower part (20 to 30 inches thick): 35 to 60 percent

Diagnostic Horizons and Features:
mollic epipedon: 26 to 50 inches thick
depth to aquic conditions and loamy-skeletal material (2Bw horizon): 20 to 30 inches from mineral surface

Major Horizons:
A horizons:
color, moist: 5YR 2.5/1, 2.5/2, 3/1, 3/2; 7.5YR 3/2; 10YR 3/3
color, dry: 5YR 2.5/2, 3/2; 7.5YR 4/2, 4/3, 5/2, 5/3
texture: SIL, L
clay content: 15 to 25 percent
rock fragment content: 0 to 10 percent
gravel: 0 to 10 percent
reaction: neutral to slightly alkaline; pH: 6.6 to 7.8
organic carbon: 1.5 to 4.7 percent

2Bw horizon:
color, moist: 5YR 2.5/2, 4/2; 7.5YR 2.5/2, 3/1, 3/2
color, dry: 7.5YR 4/3, 5/2, 5/3, 6/1, 6/3
texture: STV-SCL, GRV-SCL,
clay content: 20 to 35 percent
rock fragment content: 35 to 55 percent
gravel: 5 to 25 percent
cobbles: 5 to 15 percent
stones: 0 to 25 percent
reaction: neutral to slightly alkaline; pH: 6.6 to 7.8
organic carbon: 0.6 to 1.0 percent

2C horizon:
color, moist: 5YR 3/2; 7.5YR 2.5/2, 3/2
color, dry: 7.5YR 4/3, 5/2, 5/3; 10YR 5/2
texture: STX-LS, CBX-LS, CBX-SL, GRX-SL, STX-SL
clay content: 5 to 15 percent
rock fragment content: 60 to 75 percent
gravel: 25 to 50 percent
cobbles: 5 to 25 percent
stones: 0 to 25 percent
reaction: neutral to slightly alkaline; pH: 6.6 to 7.8
organic carbon: 0.3 to 0.6 percent

COMPETING SERIES: This is the Lismore series. Lismore soils have a 2Bk horizons with carbonate accumulations; no rock fragments throughout the series control section; formed in silty sediments over till on till plains

GEOGRAPHIC SETTING:
Landform: low terraces on mountain valley floors
Slope gradient: 0 to 5 percent
Parent material: alluvium
Lithology: mixed rocks
Elevation: 3,200 to 4,200 feet
Climate: cold, wet winters and warm, moist summers
Mean annual precipitation: 20 to 26 inches
Mean annual air temperature: 42 to 45 degrees F
Frost-free period: 50 to 125 days

GEOGRAPHICALLY ASSOCIATED SOILS:
Campcreek: on dissected relict valley fill remnants under big sagebrush
Melloe (T): on poorly drained floodplain depressions under wet medow vegetation
Witknee (T): on somewhat poorly drained alluvial terraces under moist meadow vegetation

DRAINAGE AND PERMEABILITY:
Drainage: somewhat poorly drained
Permeability: moderate over moderately slow

USE AND VEGETATION:
Use: woodland, watershed, wildlife habitat and recreation
Native vegetation: grand fir, Douglas fir, Engelmann spruce, lodgepole pine, ponderosa pine, black hawthorn, baldhip rose, birch spiraea, mallow ninebark, common snowberry, Scoulers willow, striped coral root, Oregon boxwood, longstalk clover, common yarrow, heartleaf arnica, woods strawberry, common horsetail, starry false Solomons seal, slender cinquefoil, Kentucky bluegrass, mountain brome, common timothy, blue wildrye, and Idaho fescue.
Plant associations: Dominant: PIEN/COST; may include: ABGR/SYAL, PSME/SPBE with CRDO2, PSME/SYAL and PIEN/SETR

DISTRIBUTION AND EXTENT:
MLRA 10
Distribution: Blue Mountains and Wallowa Mountains of northeastern Oregon
Extent: small

MLRA SOIL SURVEY REGIONAL OFFICE (MO) RESPONSIBLE: Portland, Oregon

SERIES PROPOSED: Wallowa County, Oregon 2007. The name is coined.

REMARKS: Diagnostic horizons and features recognized in this pedon are:
mollic epipedon: 0 to 43 inches; A1, A2, 2Bw
particle-size control section: 10 to 40 inches; A1, A2, 2Bw average 29 percent rock fragments
aquic conditions and redox depletions: 24 to 61 inches; 2Bw and 2C

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National Cooperative Soil Survey
U.S.A.