LOCATION MOUNTSTONE              WA

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

MOUNTSTONE SERIES

Landscape--mountains
Landform--glacial valley walls
Slope--0 to 100 percent
Parent material--colluvium from metasedimentary rock
Mean annual precipitation--about 1750 mm
Mean annual air temperature--about 4 degrees C
Depth class--very deep
Drainage class--well drained
Soil moisture regime--udic
Soil temperature regime--cryic
Soil moisture subclass--typic

TAXONOMIC CLASS: Loamy-skeletal, isotic Typic Dystrocryepts

TYPICAL PEDON: Mountstone gravelly silt loam on a west facing, forested glacial valley wall with a slope of 25 percent and an elevation of 1450 m. (The soil was moist throughout when described.)

A--0 to 14 cm; dark yellowish brown (10YR 3/4) dry; very dark grayish brown (10YR 3/2) gravelly silt loam; weak fine granular structure; slightly hard, friable, slightly sticky, slightly plastic; many very fine and common fine roots; many very fine irregular pores; 25 percent gravel; very strongly acid (pH 4.6); abrupt smooth boundary

Bw1--14 to 36 cm; dark yellowish brown (10YR 4/6) dry, dark yellowish brown (10YR 3/4) extremely gravelly loam; weak very fine subangular blocky structure; soft, very friable, slightly sticky, slightly plastic; many very fine and common fine roots; many very fine irregular pores; 60 percent gravel; very strongly acid (pH 4.7); abrupt wavy boundary

Bw2--36 to 72 cm; yellowish brown (10YR 5/4) dry, dark yellowish brown (10YR 4/4) extremely gravelly loam; weak very fine subangular blocky structure; soft, very friable, slightly sticky, slightly plastic; common very fine and few fine roots; many very fine irregular pores; 60 percent gravel, 10 percent cobbles; very strongly acid (pH 4.8); gradual smooth boundary

Bw3--72 to 150 cm; yellowish brown (10YR 5/4) dry, dark yellowish brown (10YR 3/4) extremely gravelly sandy loam; weak very fine subangular blocky structure; soft, very friable, slightly sticky, slightly plastic; common very fine roots; many very fine irregular pores; 55 percent gravel, 10 percent cobbles; very strongly acid (pH 4.8); gradual smooth boundary

TYPE LOCATION: Clallam County, Washington; on Obstruction Point road near Steeple rock in Olympic National Park
Latitude--47.9620600
Longitude-- -123.4571100
Datum--WGS84

RANGE IN CHARACTERISTICS:
Mean annual soil temperature--4 to 7 degrees C

Particle-size control section
*Clay content--8 to 18 percent
*Total rock fragment content--40 to 75 percent
*Gravel content--40 to 75 percent
*Cobble content--0 to 20 percent
*Stone content--0 to 15 percent

A horizon
Value--3 or 4 dry or moist
Chroma--2 to 4 dry or moist
Fine-earth texture--silt loam, loam, sandy loam
Clay content--8 to 18 percent
Total rock fragment content--10 to 40 percent
Gravel content--10 to 40 percent
Cobble content--0 to 15 percent
Reaction--4.5 to 5.5
Thickness--10 to 20 cm

Bw1, Bw2, and Bw3 horizons
Value--3 to 6 dry or moist
Chroma--4 o 6 dry or moist
Fine-earth texture--silt loam, loam, sandy loam
Clay content--8 to 18 percent
Total rock fragment content--40 to 75 percent
Gravel content--40 to 75 percent
Cobble content--0 to 20 percent
Stone content--0 to 15 percent
Reaction--4.5 to 5.5
Combined thickness--more than 100 cm

COMPETING SERIES:
Bensley--particle size control section contains 18 to 30 percent clay
Fallriver--contains an albic horizon, particle size control section contains 15 to 30 percent mica
Henson--mean annual soil temperature is 0 to 4 degrees C
Stuyahok--mean annual soil temperature is 0 to 2 degrees C
Golsovia--paralithic contact within 100 to 150 cm of the soil surface
Endlich--B horizon hue is 7.5YR or redder
Kanguq--mean annual soil temperature is -1 to 3 degrees C
Sharp--lithic contact within 100 to 150 cm of the soil surface
Cascadecreek and Grandpass --mean annual soil temperature is 0 to 3 degrees C
Endlich and Marmotlake--lithic contact within 50 to 100 cm of the soil surface

GEOGRAPHIC SETTING:
Elevation--1100 to 1500 m
Climate--cool, dry summers; cold, wet winters
Mean annual precipitation--1500 to 2000 mm
Mean annual air temperature--2 to 6 degrees C
Frost-free period--60 to 90 days

GEOGRAPHICALLY ASSOCIATED SOILS:
Cultuscreek--lithic contact within 25 to 50 cm of the soil surface; structural benches
Lollah--umbric epipedon; similar landforms
Ringlake--aquic conditions within 0 to 50 cm of the mineral soil surface, histic epipedon; depressions on similar landforms
Lakedilly--aquic conditions within 0 to 50 cm of the mineral soil surface; depressions on similar landforms

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

USE AND VEGETATION:
Use--wildlife habitat, recreation
Potential natural vegetation--mountain hemlock, Pacific silver fir, black huckleberry, oval-leaf blueberry, common beargrass, prince's pine

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

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

SERIES PROPOSED: Olympic National Park, Clallam County, Washington 2023; name from Mount Stone in Olympic National Park

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 14 to 150 cm

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National Cooperative Soil Survey
U.S.A.