LOCATION MOUNTAPPLETON WA
Tentative Series
IRD. MGR/AJF/MPR
01/2025
MOUNTAPPLETON SERIES
Landscape--mountains
Landform--seeps and drainageways on glacial valley walls
Slope--35 to 100 percent
Parent material--colluvium from metasedimentary rock
Mean annual precipitation--about 2250 mm
Mean annual air temperature--about 10 degrees C
Depth class--very deep
Drainage class--somewhat poorly drained
Soil moisture regime--udic
Soil temperature regime--mesic
Soil moisture subclass--oxyaquic
TAXONOMIC CLASS: Loamy-skeletal, isotic, mesic Andic Oxyaquic Humudepts
TYPICAL PEDON: Mountappleton silt loam on a northwest facing, forested valley wall with a slope of 70 percent and an elevation of 435 m. (The soil was moist throughout when described.)
Oi--0 to 1 cm; slightly decomposed plant material; abrupt smooth boundary
A--1 to 12 cm; brown (10YR 4/3) dry, dark brown (10YR 3/3) silt loam; moderate fine granular structure; soft, very friable, moderately sticky, moderately plastic; moderately smeary; few very fine and fine roots; few fine irregular and tubular pores; 10 percent gravel; very strongly acid (pH 4.6); abrupt smooth boundary
Bw1--12 to 41 cm; brown (10YR 4/3) dry, dark brown (10YR 3/3) very gravelly silt loam; moderate medium subangular blocky structure; slightly hard, friable, moderately sticky, moderately plastic; weakly smeary; few fine roots; few fine irregular pores; 25 percent gravel and 10 percent cobbles; very strongly acid (pH 4.7); abrupt smooth boundary
Bw2--41 to 80 cm; brown (10YR 5/3) dry, brown (10YR 4/3) very gravelly loam; weak fine subangular blocky structure; soft, very friable, moderately sticky, moderately plastic; few fine irregular and common medium interstitial pores; 40 percent gravel, 5 percent cobbles; very strongly acid (pH 4.7); clear smooth boundary
Bw3--80 to 150 cm; light yellowish brown (10YR 6/4) dry, brown (10YR 5/3) very gravelly loam; weak very fine subangular blocky structure; soft, very friable, moderately sticky, moderately plastic; common medium interstitial pores; 40 percent gravel and 15 percent cobbles; very strongly acid (pH 4.8); clear smooth boundary
TYPE LOCATION: Clallam County, Washington; Rugged Ridge trail in Olympic National Park.
Latitude--47.9275240
Longitude-- -124.1645170
Datum--WGS84
RANGE IN CHARACTERISTICS:
Mean annual soil temperature--8 to 13 degrees C
Umbric epipedon thickness--18 to 45 cm
Particle-size control section
*Clay content--8 to 18 percent
*Total rock fragment content--35 to 65 percent
*Gravel content--15 to 50 percent
*Cobble content--0 to 40 percent
*Stone content--0 to 20 percent
Oi horizon
Thickness--0 to 8 cm
A horizon
Value--2 or 3 moist, 3 or 4 dry
Chroma--2 or 3 moist or dry
Fine-earth texture--silt loam, loam, or sandy loam
Clay content--8 to 18 percent
Total rock fragment content--0 to 35 percent
Gravel content--0 to 35 percent
Cobble content--0 to 10 percent
Reaction--4.5 to 5.5
Thickness--8 to 20 cm
Bw1 horizon
Value--2 or 3 moist, 3 or 4 dry
Chroma--2 or 3 moist or dry
Fine-earth texture--silt loam, loam, or sandy loam
Clay content--8 to 18 percent
Total rock fragment content--35 to 60 percent
Gravel content--15 to 50 percent
Cobble content--0 to 40 percent
Stone content--0 to 20 percent
Reaction--4.5 to 5.5
Thickness--20 to 40 cm
Bw2 and Bw3 horizons
Value--4 to 6 dry, 5 to 7 dry
Chroma--3 or 4, moist or dry
Fine-earth texture--silt loam, loam, or sandy loam
Clay content--8 to 18 percent
Total rock fragment content--35 to 60 percent
Gravel content--15 to 50 percent
Cobble content--0 to 40 percent
Stone content--0 to 20 percent
Reaction--4.5 to 5.5
Combined thickness--80 to 120 cm
COMPETING SERIES: None
GEOGRAPHIC SETTING:
Elevation--300 to 800 m
Climate--warm, dry summers; mild, wet winters
Mean annual precipitation--1750 to 2750 mm
Mean annual air temperature--8 to 12 degrees C
Frost-free period--180 to 240 days
GEOGRAPHICALLY ASSOCIATED SOILS:
Mountdeception--well drained; similar landforms
Irely--well drained, spodic and albic horizons; similar landforms
Sentinelpeak--well drained, no andic soil subgroup features; similar landforms
Dodgerpoint--well drained, lithic contact within 25 to 50 cm; similar landforms
DRAINAGE AND SATURATED HYDRAULIC CONDUCTIVITY:
Drainage class--somewhat poorly
Saturation in normal years--seasonally high water table top depth of 25 to 50 cm November through April and 50 to 100 cm May through July, not saturated August through October
Flooding--none
Ponding--none
Saturated hydraulic conductivity (Ksat)--high or very high throughout
USE AND VEGETATION:
Use--wildlife habitat, recreation
Potential natural vegetation--western redcedar, western hemlock, salmonberry, devilsclub
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 Mount Appleton in Olympic National Park
REMARKS:
Diagnostic horizons and other features in this pedon:
*Particle-size control section--zone from 26 to 101 cm
*Umbric epipedon--zone from 1 to 41 cm
*Cambic horizon--zone from 41 to 150 cm
*Andic subgroup features--zone from 1 to 41 cm; AO extractable Al plus Fe is 1 to 2 percent and Db is 0.9 to 1.0 g/cm3
*Oxyaquic conditions--saturation in one or more layers within 100 cm of the mineral soil surface for 30 or more cumulative days of the year
National Cooperative Soil Survey
U.S.A.