LOCATION LOWDIVIDE               WA

Tentative Series
IRD. MGR/AJF/MPR
01/2025

LOWDIVIDE SERIES

Landscape--river valley
Landform--alluvial terraces
Slope--0 to 15 percent
Parent material--alluvium
Mean annual precipitation--about 2250 mm
Mean annual air temperature--about 10 degrees C
Depth class--very deep
Drainage class--well drained
Soil moisture regime--udic
Soil temperature regime--mesic
Soil moisture subclass--typic

TAXONOMIC CLASS: Coarse-loamy over sandy or sandy-skeletal, mixed, active, mesic Typic Dystrudepts

TYPICAL PEDON: Lowdivide loam on a forested alluvial terrace with a slope of 1 percent and an elevation of 110 m. (The soil was moist throughout when described.)

Oi--0 to 2 cm; slightly decomposed plant material; abrupt smooth boundary

A--2 to 12 cm; brown (10YR 4/3) dry, very dark grayish brown (10YR 3/2) loam; strong fine granular structure; slightly hard, friable, slightly sticky, moderately plastic; weakly smeary; many very fine, few medium, and common fine roots; many very fine and fine irregular and few very fine tubular pores; very strongly acid (pH 4.6); clear smooth boundary

Bw1--12 to 22 cm; brown (10YR 4/3) dry, very dark grayish brown (10YR 3/2) loam; moderate fine subangular blocky structure; slightly hard, friable, slightly sticky, moderately plastic; weakly smeary; few very fine, fine and coarse roots; few very fine tubular and common fine irregular pores; very strongly acid (pH 4.7); clear smooth boundary

Bw2--22 to 56 cm; grayish brown (2.5Y 5/2) dry, dark grayish brown (2.5Y 4/2) silt loam; moderate medium subangular blocky structure; slightly hard, friable, moderately sticky, moderately plastic; few very fine and fine roots; common very fine and fine tubular and common fine irregular pores; very strongly acid (pH 4.7); abrupt smooth boundary

BC--56 to 76 cm; dark grayish brown (2.5Y 4/2) dry, very dark gray (2.5Y 3/1) extremely gravelly loamy sand; weak very fine subangular blocky structure; soft, very friable; few fine roots; few fine irregular pores; 65 percent gravel; very strongly acid (pH 4.8); abrupt smooth boundary

C--76 to 150 cm; dark gray (10YR 4/1) dry, very dark gray (10YR 3/1) extremely gravelly loamy sand; structureless single grain; loose, many very fine and fine interstitial pores; 70 percent gravel; very strongly acid (pH 4.8); abrupt smooth boundary

TYPE LOCATION: Clallam County, Washington
Latitude--48.0249790
Longitude-- -123.5913860
Datum--WGS84

RANGE IN CHARACTERISTICS:
Mean annual soil temperature--8 to 13 degrees C

Particle-size control section--upper 20 to 40 cm
*Clay content--8 to 17 percent
*Sand content--30 to 45 percent
*Total rock fragment content--0 to 25 percent
*Gravel content--0 to 25 percent
*Cobble content--0 to 10 percent

Particle-size control section--lower 60 to 80 cm
*Clay content--1 to 5 percent
*Total rock fragment content--50 to 75 percent
*Gravel content--50 to 70 percent
*Cobble content--0 to 35 percent
*Stone content--0 to 20 percent

Oi horizon
Thickness--0 to 5 cm

A horizon
Value--2 or 3 moist, 3 or 4 dry
Chroma--2 or 3, moist or dry
Fine-earth texture--silt loam or loam
Clay content--8 to 17 percent
Total rock fragment content--0 to 25 percent
Gravel content--0 to 25 percent
Cobble content--0 to 10 percent
Reaction--4.5 to 5.5
Thickness--8 to 15 cm

Bw1 and Bw2 horizons
Hue--10YR or 2.5Y
Value--3 or 4 moist, 4 or 5 dry
Chroma--2 to 4, moist or dry
Fine-earth texture--silt loam or loam
Clay content--8 to 17 percent
Total rock fragment content--0 to 25 percent
Gravel content--0 to 25 percent
Cobble content--0 to 10 percent
Reaction--4.5 to 5.5
Combined thickness--35 to 55 cm

BC and C horizons
Hue--10YR or 2.5Y
Value--3 or 4 moist, 4 or 5 dry
Chroma--1 to 3 moist or dry
Fine-earth texture--loamy sand or sand
Clay content--1 to 5 percent
Total rock fragment content--50 to 75 percent
Gravel content--50 to 75 percent
Cobble content--0 to 30 percent
Stone content--0 to 20 percent
Reaction--4.5 to 5.5
Combined thickness--more than 80 cm

COMPETING SERIES:
Agawam, Barnstable, Branford, Haven--lower part of particle-size control section has less than 35 percent coarse fragments
Narragansett--lower part of the particle size control section contains 10 to 50 percent coarse fragments

GEOGRAPHIC SETTING:
Elevation--100 to 500 m
Climate--warm, dry summers; mild, wet winters
Mean annual precipitation--1750 to 2750 mm
Mean annual air temperature--8 to 12 C
Frost-free period--180 to 240 days

GEOGRAPHICALLY ASSOCIATED SOILS:
Fourstream--no cambic horizon, flooding occurs more frequently; similar landforms
Stukey--more than 35 percent coarse fragments throughout the particle size control section; similar landforms

DRAINAGE AND SATURATED HYDRAULIC CONDUCTIVITY:
Drainage class--well drained
Saturation in normal years--none
Flooding--rare, brief
Ponding--none
Saturated hydraulic conductivity (Ksat)--high or very high throughout

USE AND VEGETATION:
Use--wildlife habitat, recreation
Potential natural vegetation--western hemlock, bigleaf maple, salmonberry, vine maple, western swordfern, small enchanter's nightshade, threepetal bedstraw, redwood-sorrel, and coastal hedgenettle

DISTRIBUTION AND EXTENT: Olympic Mountains, Washington; MLRA 1; small extent

SOIL SURVEY REGIONAL OFFICE (SSRO) RESPONSIBLE: Bozeman, Montana

SERIES PROPOSED: Olympic National Park, Clallam County, Washington 2023; name from Lowdivide Camp in Olympic National Park

REMARKS:
Diagnostic horizons and other features in this pedon:
*Particle-size control section--zone from 27 to 102 cm
*Ochric epipedon
*Cambic horizon--zone from 12 to 56 cm
*Strongly contrasting particle-size classes--zone from 27 to 56 cm is coarse-loamy, and zone from 56 to 102 cm is sandy-skeletal

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National Cooperative Soil Survey
U.S.A.