LOCATION MOUNTSUN                OR

Tentative Series
IRD. KBC/BTH
02/2025

MOUNTSUN SERIES

Landscape--pumice mantled plateau
Landform--tephra volcanic fields on scarp slopes
Slope--10 to 35 percent
Parent material--coarse pumiceous volcanic ash and pumice parafragments
Mean annual precipitation--about 730 mm
Mean annual air temperature--about 6 degrees C
Depth class--very deep
Drainage class--somewhat excessively drained
Soil moisture regime--xeric
Soil temperature regime--frigid
Soil moisture subclass--typic

TAXONOMIC CLASS: Ashy, glassy, frigid Typic Vitrixerands

TYPICAL PEDON: Mountsun ashy loamy sand, mixed coniferous forest, on a tephra volcanic field on a southwest-facing scarp with a slope of 8 percent, at an elevation of 1380 m

Oi--0 to 6 cm; slightly decomposed plant material; abrupt smooth boundary

A--6 to 10 cm; ashy loamy sand, brown (10YR 4/3) dry, very dark grayish brown (10YR 3/2) moist; moderate fine and medium subangular blocky structure; soft, very friable, nonsticky and nonplastic; common very fine and fine roots throughout; common fine dendritic tubular pores; 3 percent fine pumice paragravel; slightly acid (pH 6.3); gradual smooth boundary

Bw1--10 to 24 cm; ashy loamy sand, pale brown (10YR 6/3) dry, brown (10YR 4/3) moist; moderate fine and medium subangular blocky structure; soft, very friable, nonsticky and nonplastic; common very fine to medium roots throughout; common fine dendritic tubular pores; 12 percent fine medium pumice paragravel; slightly acid (pH 6.5); gradual smooth boundary

Bw2--24 to 52 cm; paragravelly ashy loamy sand, pale brown (10YR 6/3) dry, brown (10YR 4/3) moist; weak medium subangular blocky structure; loose, very friable, nonsticky and nonplastic; common very fine to very coarse roots throughout; common fine dendritic tubular pores; 13 percent fine to coarse pumice paragravel, 3 percent fine and medium andesite gravel; neutral (pH 6.9); gradual smooth boundary

BC--52 to 120 cm; ashy loamy sand, 80 percent pinkish gray (7.5YR 7/2) and 20 percent brown (7.5YR 5/3) dry, 80 percent brown (7.5YR 5/3) and 20 percent strong brown (7.5YR 4/6) moist; weak coarse subangular blocky structure; loose, very friable, nonsticky and nonplastic; few very fine and common fine to coarse roots throughout; common fine dendritic tubular pores; 7 percent fine and medium pumice paragravel, 3 percent fine andesite gravel; neutral (pH 7.0); gradual smooth boundary

CB--120 to 180 cm; paragravelly ashy sand, 80 percent pink (7.5YR 7/3) and 20 percent brown (7.5YR 5/4) dry, 80 percent light brown (7.5YR 6/3) and 20 percent strong brown (7.5YR 4/6) moist; massive; loose, very friable, nonsticky and nonplastic; few very fine to medium roots throughout; common dendritic tubular pores; 13 percent fine and medium pumice paragravel, 3 percent fine andesite gravel; neutral (pH 7.0); abrupt smooth boundary

C--180 to 205 cm; paragravelly ashy sand, light brownish gray (10YR 6/2) dry, dark grayish brown (10YR 4/2) moist; single grain; loose, very friable, nonsticky and nonplastic; 10 percent fine and medium pumice paragravel, 5 percent fine andesite gravel; neutral (pH 7.0)

TYPE LOCATION: Klamath County, Oregon; about 2.2 miles northeast of the town of Fort Klamath, OR; about 540 m south and 520 m east of the northwest corner of section 11, T. 33 S., R. 7.5 E.; Willamette Meridian; Fort Klamath, Oregon U. S. Geological Survey quadrangle; latitude 42.728680 degrees north, longitude 121.969880 degrees west, datum WGS 84 (coordinates derived from GPS unit)

RANGE IN CHARACTERISTICS:

Soil Temperature: frigid regime
*Mean annual soil temperature-- 6.4 to 8.0 degrees C
*Mean summer soil temperature-- 11.4 to 13.0 degrees C
*Mean winter soil temperature-- 2.5 to 4.1 degrees C
*Moisture control section--30 to 90 cm below the soil surface; xeric regime; dry for 45 to 60 consecutive days following the summer solstice
*Rock fragments--pumice paragravel; andesite or basalt gravel

Particle-size control section:
*Clay content--0 to 5 percent
*Rock fragment content--0 to 10 percent
*Pumice pararock fragment content--5 to 34 percent
*Total rock and pararock fragment content--5 to 34 percent

Estimated properties:
*Ammonium oxalate extractable Al plus 1/2Fe--0.2 to 0.4 percent
*Medium to very coarse sand in the .02 to 2.0 mm fraction--greater than 50 percent
*P retention--25 to 50 percent
*Volcanic glass content--75 to 100 percent
*Moist bulk density--0.7 to 1.0 g/cm3
*1/3-bar bulk density--0.5 to 0.9 g/cm3
*1500 kPa water (air-dried samples)--3 to 12 percent

Oi horizon (and Oe horizon, when present)
*Thickness--0 to 15 cm

A horizon
Value--2 to 4 moist, 4 to 6 dry
Chroma--2 to 3 moist, 1 to 3 dry
Fine-earth texture--ashy loamy sand, ashy loamy coarse sand
Clay content--0 to 5 percent
Pumice paragravel content--0 to 14 percent
Reaction--moderately acid to neutral (pH 5.6 to 7.3)
Thickness--3 to 15 cm

Bw horizons
Hue--10YR or 7.5YR moist or dry
Value--3 to 5 moist, 4 to 6 dry
Chroma--2 to 4 moist or dry
Fine-earth texture--ashy loamy sand, ashy loamy coarse sand, ashy coarse sand
Clay content--0 to 5 percent
Andesite gravel content--0 to 10 percent
Pumice paragravel content--5 to 20 percent
Total rock and pararock fragment content--5 to 30 percent
Reaction--moderately acid to neutral (pH 5.6 to 7.3)
Thickness--20 to 135 cm

BC and CB horizons (where present)
Hue--10YR or 7.5YR moist or dry
Value--3 to 8 moist, 5 to 8 dry
Chroma--2 to 8 moist, 2 to 6 dry
Fine-earth texture--ashy loamy sand, ashy loamy coarse sand, ashy coarse sand
Clay content--0 to 5 percent
Andesite gravel content--0 to 10 percent
Pumice paragravel content--5 to 40 percent
Total rock and pararock fragment content--5 to 50 percent
Reaction--moderately acid to slightly alkaline (pH 5.6 to 7.8)
Thickness--0 to 76 cm

C horizon (where present)
Hue--10YR or 7.5YR moist or dry
Value--3 to 8 moist, 5 to 8 dry
Chroma--2 to 8 moist, 2 to 6 dry
Fine-earth texture--ashy loamy sand, ashy sand, ashy coarse sand
Clay content--0 to 5 percent
Andesite gravel content--0 to 10 percent
Pumice paragravel content--15 to 50 percent
Total rock and pararock fragment content--15 to 55 percent
Reaction--moderately acid to slightly alkaline (pH 5.6 to 7.8)

COMPETING SERIES:
Chiwawa--parent materials include glacial outwash; on terraces with 0 to 3 percent slopes; 30 to 60 percent volcanic glass; 1.0 to 2.0 percent Al+1/2 Fe; 0.65 to 0.85 g/cc moist bulk density; 15 to 35 percent pumice in the particle-size control section; 90 to 120 frost-free days
Polander--100 to 150 cm to paralithic contact (deep); 50 to 70 percent glass; 10 to 18 percent clay in the particle-size control section
Thow--parent materials include glacial till; 30 to 60 percent volcanic glass; 1.0 to 2.0 percent Al+1/2 Fe; 5 to 35 percent pumice in the particle-size control section; 85 to 120 frost-free days
Vinegar--1.0 to 2.0 percent Al+1/2Fe; on glaciated mountains; parent materials include glacial outwash and some till; 85 to 120 frost-free days

GEOGRAPHIC SETTING:
Elevation--1270 to 1600 m
Climate--cold, moist winters and cool, dry summers
Mean annual precipitation--460 to 1000 mm
Mean annual air temperature--5.2 to 7.0 degrees C
Frost-free period--40 to 70 days

GEOGRAPHICALLY ASSOCIATED SOILS:
Mousetails--similar landforms; 30 to 85 percent pumice in the particle-size control section; 100 to over 200 cm to a buried paleosol
Uffda--similar landforms; ashy-skeletal over loamy-skeletal particle-size class; 60 to 90 cm to a buried paleosol
Steiger--similar landforms; cyric soil temperature regime; 5 to 35 percent pumice in the particle-size control section; 100 to over 150 cm to a buried paleosol
Lapine--on lava plains, hills, and cinder cones; cryic soil temperature regime; 35 to 85 percent pumice in the particle-size control section; 100 to over 150 cm to a buried paleosol

DRAINAGE AND SATURATED HYDRAULIC CONDUCTIVITY:
Drainage class--somewhat excessively drained
Saturated hydraulic conductivity--high to very high

USE AND VEGETATION:
Use--timber production, wildlife habitat, recreation
Vegetation--incense cedar, sugar pine, ponderosa pine, Douglas-fir, serviceberry, Greenleaf manzanita, tall Oregon grape, golden chinquapin, snowbrush, common prince's pine, antelope bitterbrush, dwarf rose, arrowleaf balsamroot, woodland strawberry, squirreltail

DISTRIBUTION AND EXTENT: Cascade Mountains, Eastern Slope, Oregon; MLRA 6; small extent

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

SERIES PROPOSED: Klamath County, Oregon, 2019
Origin of the name--the name is coined, based off the name of a nearby road, Sun Mountain Road.

REMARKS:
Diagnostic horizons and other features recognized in this pedon
*Particle-size control section--the zone from 6 to 106 cm
*Ochric epipedon
*Andic soil properties--all horizons
*Volcanic glass--all horizons

ADDITIONAL DATA:
NASIS Site ID: 2019OR035058; NASIS Pedon ID: 2019OR035058

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National Cooperative Soil Survey
U.S.A.