LOCATION FLETT                   WA

Established Series
IRD. SMB/PHR/MPR
07/2017

FLETT SERIES

Landscape--river valleys
Landform--flood plains, terraces
Slope--0 to 15 percent
Parent material--alluvium derived from andesite mixed with volcanic ash
Mean annual precipitation--about 2000 mm
Mean annual air temperature--about 5 degrees C
Depth class--very deep
Drainage class--somewhat excessively drained
Soil moisture regime--udic
Soil temperature regime--cryic
Soil moisture subclass--typic

TAXONOMIC CLASS: Ashy-skeletal, glassy Vitrandic Dystrocryepts

TYPICAL PEDON: Flett very stony ashy coarse sandy loam on a forested flood plain with a slope of 3 percent and at an elevation of 875 m (When described on May 16, 2012, the soil was moist throughout.)

Oi--0 to 2 cm; slightly decomposed plant material; common very fine roots; very strongly acid (pH 4.5); abrupt wavy boundary

Oe--2 to 4 cm; moderately decomposed plant material; common very fine and fine and few medium roots; very strongly acid (pH 4.5); clear wavy boundary

A--4 to 32 cm; very stony ashy coarse sandy loam, dark gray (10YR 4/1) dry, black (10YR 2/1) moist; weak fine subangular blocky structure; soft, very friable, nonsticky and nonplastic; few very fine to coarse roots; common fine interstitial pores; 5 percent fine gravel, 10 percent medium and coarse gravel, 15 percent cobbles, and 15 percent stones; strongly acid (pH 5.4); gradual irregular boundary

C1--32 to 85 cm; extremely stony ashy loamy sand, dark gray (10YR 4/1) dry, black (10YR 2/1) moist; single grain; loose, nonsticky and nonplastic; few very fine and fine roots; common fine interstitial pores; 5 percent fine gravel, 30 percent medium and coarse gravel, 15 percent cobbles, 15 percent stones, and 5 percent boulders; strongly acid (pH 5.4); clear wavy boundary

C2--85 to 115 cm; extremely stony ashy loamy coarse sand, dark gray (10YR 4/1) dry, black (10YR 2/1) moist; single grain; loose, nonsticky and nonplastic; common very fine and few fine and medium roots; common fine interstitial pores; 10 percent fine gravel, 20 percent medium and coarse gravel, 15 percent cobbles, 15 percent stones, and 5 percent boulders; moderately acid (pH 5.7); abrupt wavy boundary

C3--115 to 150 cm; very gravelly ashy loamy sand, dark gray (10YR 4/1) dry, black (10YR 2/1) moist; single grain; loose, nonsticky and nonplastic; few very fine roots; common fine interstitial pores; 15 percent fine gravel, 15 percent medium and coarse gravel, and 5 percent cobbles; moderately acid (pH 5.7)

TYPE LOCATION: Pierce County, Washington, about 2.5 km southeast of Gobblers Knob, along Tahoma Creek and West Side Road in Mount Rainier National Park; about 305 m north and 760 m west of the southeast corner of section 14, T. 15 N., R. 7 E., Willamette Meridian; Mount Wow, Washington, U.S. Geological Survey quadrangle; latitude 46.78145 degrees north, longitude -121.88634 degrees west, datum WGS 84 (coordinates determined with a GPS)

RANGE IN CHARACTERISTICS:
Mean annual soil temperature--3 to 8 degrees C
Soil moisture control section--dry less than 45 consecutive days in June through October
Thickness of cambic horizon--25 to 40 cm

All mineral horizons
*Organic carbon content--less than 0.6 percent
*Volcanic glass content--50 to 75 percent glass and glass-coated minerals
*Ammonium oxalate Al plus 1/2 Fe--less than 0.4 percent
*Reaction--5.1 to 6.0

Particle-size control section
*Clay content--0 to 7 percent
*Rock fragment content--35 to 85 percent total, including 15 to 50 percent fine to coarse gravel, 5 to 25 percent cobbles, 5 to 25 percent stones, and 0 to 10 percent boulders

O horizon
*In lieu of texture--slightly decomposed plant material, moderately decomposed plant material
*Combined thickness--as much as 7 cm

A horizon
*Value--2 or 3 moist, 3 to 5 dry
*Chroma--1 or 2 moist or dry
*Fine-earth texture--ashy coarse sandy loam, ashy loamy very fine sand
*Rock fragment content--15 to 60 percent total, including 5 to 20 percent fine gravel, 5 to 30 percent medium and coarse gravel, 0 to 25 percent cobbles, 0 to 25 percent stones, and 0 to 10 percent boulders
*Thickness--15 to 40 cm

C1 horizon
*Hue--7.5YR, 10YR, variegated mineral colors
*Value--2 or 3 moist, 3 to 5 dry
*Chroma--1 to 3 moist or dry
*Fine-earth texture--ashy loamy sand, ashy sand, ashy sandy loam
*Rock fragment content--35 to 85 percent total, including 5 to 25 percent fine gravel, 5 to 40 percent medium and coarse gravel, 5 to 30 percent cobbles, 0 to 25 percent stones, and 0 to 10 percent boulders
*Thickness--35 to 60 cm

C2 and C3 horizons
*Hue--7.5YR, 10YR, variegated mineral colors
*Value--2 or 3 moist, 3 to 5 dry
*Chroma--1 to 3 moist or dry
*Fine-earth texture--ashy loamy sand, ashy loamy coarse sand, ashy sandy loam, ashy coarse sandy loam
*Rock fragment content--35 to 85 percent total, including 5 to 25 percent fine gravel, 5 to 40 percent medium and coarse gravel, 5 to 30 percent cobbles, 0 to 25 percent stones, and 0 to 10 percent boulders
*Combined thickness--50 to 100 cm

COMPETING SERIES:
Lasac--andic properties in upper 25 to 36 cm of mineral soil material

GEOGRAPHIC SETTING:
Elevation--530 to 2100 m
Climate--cool, dry summers; cold, wet winters
Mean annual precipitation--1600 to 2800 mm
Mean annual air temperature--2 to 7 degrees C
Frost-free period--60 to 90 days

GEOGRAPHICALLY ASSOCIATED SOILS:
Narada--less than 35 percent rock fragments in particle-size control section; aquic conditions with an upper limit between 50 and 75 cm from top of mineral soil surface; on similar landforms
Frogheaven--aquic conditions within 25 cm of the mineral soil surface; in depressions of flood plains and terraces
Longmire, Vantrump--andic soil properties throughout mineral horizons; on nearby valley walls and debris aprons
Summerland--umbric epipedon; andic soil properties throughout mineral horizons; on debris cones

DRAINAGE AND SATURATED HYDRAULIC CONDUCTIVITY:
Drainage--somewhat excessively drained
Saturated hydraulic conductivity (Ksat)--very high
Frequency of flooding--rare

USE AND VEGETATION:
Use--wildlife habitat, recreation
Potential natural vegetation--black cottonwood, Sitka alder, Pacific silver fir, Engelmann spruce, subalpine fir, mountain hemlock, Alaska yellow-cedar, western hemlock, western redcedar, Douglas-fir, vine maple, western swordfern, red huckleberry, black huckleberry, five-leaved bramble, prince's pine, fireweed, Barclay's willow

DISTRIBUTION AND EXTENT: Central Cascade Mountains, Washington; MLRA 3; moderate extent

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

SERIES PROPOSED: Mount Rainier National Park, Pierce County, Washington; 2014; name from Flett Glacier in Mount Rainier National Park

REMARKS:
Diagnostic horizons and other features in this pedon
*Particle-size control section--zone from 29 to 104 cm
*Ochric epipedon
*Cambic horizon--zone from 4 to 32 cm
*Volcanic glass--zone from 4 to 150 cm

12/2017--This official series description was updated according to SSR1 Technical Note 11--Content and Format of Official Series Descriptions (revised 12/2015). Most of the changes were in formatting; no major technical changes were made.

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National Cooperative Soil Survey
U.S.A.