LOCATION NEMAH WA
Established Series
Rev. CJM/DRU/EED
04/2017
NEMAH SERIES
Landscape--drift plains, coastal plains, river valleys
Landform--depressions, terraces
Slope--0 to 5 percent
Parent material--alluvium
Mean annual precipitation--about 2300 mm
Mean annual air temperature--about 10 degrees C
Depth class--very deep
Drainage class--poorly drained
Soil moisture regime--aquic
Soil temperature regime--isomesic
Soil moisture subclass--typic
TAXONOMIC CLASS: Fine, isotic, acid, isomesic Vertic Endoaquepts
TYPICAL PEDON: Nemah silty clay loam, forested (The soil was wet when described.)
Oi--0 to 5 cm; peat
Oa--5 to 10 cm; muck, black (5YR 2/1) moist; many fine roots
A1--10 to 22 cm; silty clay loam, black (5YR 2/1) moist, very dark gray (N 3/0) dry; weak fine subangular blocky structure; hard, friable, moderately sticky and moderately plastic; many fine and medium roots; many fine tubular and interstitial pores; very strongly acid (pH 4.6); clear smooth boundary
A2--22 to 30 cm; silty clay, very dark brown (10YR 2/2) moist, dark gray (10YR 4/1) dry; weak fine subangular blocky structure, very hard, firm, very sticky and very plastic; common fine and medium roots; many fine tubular and interstitial pores; 10 percent medium prominent grayish brown (2.5Y 5/2) iron depletions and 10 percent medium prominent yellowish red (5YR 5/8) masses of oxidized iron; very strongly acid (pH 4.6); clear wavy boundary
Bg1--30 to 43 cm; clay, dark grayish brown (10YR 4/2) moist, light gray (2.5Y 7/2) dry; moderate medium prismatic structure; extremely hard, firm, very sticky and very plastic; few fine roots; many fine tubular and interstitial pores; very dark grayish brown (10YR 3/2) organic stains on vertical faces of peds; 10 percent coarse prominent strong brown (7.5YR 5/8) masses of oxidized iron and 10 percent coarse faint grayish brown (2.5Y 5/2) iron depletions; very strongly acid (pH 4.8); gradual wavy boundary
Bg2--43 to 76 cm; clay, gray (N 6/0) moist, light gray (2.5Y 7/2) dry; moderate medium prismatic structure; extremely hard, firm, very sticky and moderately plastic; few fine roots; many fine tubular and interstitial pores; very dark grayish brown (10YR 3/2) organic stains on vertical faces of peds; 10 percent coarse prominent strong brown (7.5YR 5/8) masses of oxidized iron ; very strongly acid (pH 4.8); gradual wavy boundary
Bg3--76 to 101 cm; clay, gray (N 6/0) moist, light gray (2.5Y 7/2) dry; weak medium prismatic structure; extremely hard, firm, very sticky and very plastic; few fine roots; many fine tubular and interstitial pores; 10 percent coarse prominent strong brown (7.5YR 5/8) masses of oxidized iron; extremely acid (pH 4.3); gradual wavy boundary
2Cg--101 to 150 cm; very gravelly clay, gray (N 6/0) moist, light gray (2.5Y 7/2) dry; massive; extremely hard, firm, very sticky and very plastic; 10 percent coarse prominent strong brown (7.5YR 5/8) masses of oxidized iron; 40 percent gravel; very strongly acid
TYPE LOCATION: Grays Harbor County, Washington, about 17.5 km north of Montesano on the Wynoochee Valley Road, 0.75 km south of the intersection with Upper School House Road, and 30 m east of road; about 455 m east and 70 m south of the northwest corner of section 23, T. 19 N., R. 8 W., Willamette Meridian; Wynoochee Valley SW, Washington, U.S. Geological Survey quadrangle; latitude 47.1229370 degrees north, longitude 123.6472660 degrees west, WGS 84 (coordinates estimated from PLSS details)
RANGE IN CHARACTERISTICS:
Mean annual soil temperature--10 to 12 degrees C
Depth to aquic conditions--0 to 30 cm
Particle-size control section--35 to 60 percent clay (weighted average); 0 to 25 percent total rock fragments (weighted average); reaction of 3.5 to 5.5
A horizon
Hue--5YR to 2.5Y, neutral
Value--2 or 3 moist, 3 or 4 dry
Chroma--neutral, 1 to 3 moist or dry
Fine-earth texture--silty clay loam, silty clay, silt loam
Clay content--20 to 45 percent
Gravel content--0 to 10 percent
Reaction (pH)--3.5 to 5.0
Combined thickness--10 to 20 cm
Bg1 and Bg2 horizons
Hue--10YR to 2.5Y, neutral
Value--3 to 6 moist, 6 or 7 dry
Chroma--neutral, 1 or 2 moist or dry
Fine-earth texture--clay, silty clay, silty clay loam
Clay content--35 to 60 percent
Gravel content--0 to 25 percent
Reaction (pH)--3.5 to 5.0
Combined thickness--40 to 60 cm
Bg3 horizon
Hue--10YR to 2.5Y, neutral
Value--3 to 6 moist, 4 to 7 dry
Chroma--neutral, 1 or 2 moist or dry
Fine-earth texture--clay, silty clay, silty clay loam, clay loam
Clay content--35 to 60 percent
Total rock fragment content--0 to 30 percent
Gravel content--0 to 30 percent
Cobble content--0 to 5 percent
Reaction (pH)--3.5 to 5.0
Thickness--20 to 30 cm
2Cg horizon
Hue--10YR to 2.5Y, neutral
Value--3 to 6 moist, 4 to 7 dry
Chroma--neutral, 1 or 2 moist or dry
Fine-earth texture--clay, silty clay, silty clay loam, clay loam
Clay content--27 to 60 percent
Total rock fragment content--15 to 60 percent
Gravel content--15 to 60 percent
Cobble content--0 to 10 percent
Reaction (pH)--3.5 to 5.5
COMPETING SERIES:
Tealwhit--no rock fragments and 35 to 50 percent clay in particle-size control section
GEOGRAPHIC SETTING:
Elevation--5 to 1200 m
Mean annual precipitation--1800 to 3100 mm
Mean annual air temperature--9 to 11 degrees C
Frost-free period--200 to 240 days
GEOGRAPHICALLY ASSOCIATED SOILS:
Copalis--no aquic conditions within 50 cm of the soil surface; on drift plains, mountain valleys, and mountain slopes
Hoquiam--no aquic conditions; on hillslopes and moraines
Willapa--no aquic conditions within 50 cm of the soil surface; on coastal plains
Skamo--no aquic conditions within 50 cm of the soil surface; on convex to linear alluvial fans and terraces
DRAINAGE AND SATURATED HYDRAULIC CONDUCTIVITY:
Drainage class--poorly drained
Depth to apparent seasonal water table--at the surface to a depth of 30 cm at times in October through April, at the surface to a depth of more than 200 cm at times in May through July
Flooding--none to frequent, brief periods in November through March
Ponding--frequent, long periods in October through May
Saturated hydraulic conductivity (Ksat)--low to moderately high in A horizon, very low to moderately high in Bg horizon, very low in 2Cg horizon
Ponding and the seasonal high water table in some pedons may be altered by artificial drainage.
USE AND VEGETATION:
Use--wildlife habitat, scattered areas of hay production and livestock grazing in cleared and/or artificially drained areas
Native vegetation--red alder, Sitka spruce, western redcedar, willow, redosier dogwood, Douglas spirea, salmonberry, sedges, grass, rushes, skunk cabbage
DISTRIBUTION AND EXTENT: Coastal areas of western Washington; MLRA 4a; moderate extent
MLRA SOIL SURVEY REGIONAL OFFICE (MO) RESPONSIBLE: Portland, Oregon
SERIES ESTABLISHED: Grays Harbor County (Grays Harbor County Area), Washington; 1970
REMARKS:
Diagnostic horizons and other features in this pedon
*Particle-size control section--zone from 25 to 100 cm
*Ochric epipedon
*Cambic horizon--zone from 10 to 101 cm
*Aquic conditions--zone from 5 to 150 cm
*Endosaturation--zone from 5 to 150 cm
*Redoximorphic depletions with chroma of 2 or less--zone from 22 to 43 cm
*Depth to lithologic discontinuity--101 cm
04/1994--Previously classified as fine, mixed, acid, mesic Humic Haplaquepts; classification change based on amendments to Soil Taxonomy.
10/2016--This official series description was edited according to SSR01 Technical Note--Content and Format of Official Series Descriptions (revised 12/2015).
National Cooperative Soil Survey
U.S.A.