LOCATION SIMSBUTTE               OR

Tentative Series
IRD. DCR/MPR
02/2025

SIMSBUTTE SERIES

Landscape--High Cascade volcanic fields
Landform--cinder cones
Slope--30 to 60 percent
Parent material--volcanic ash over cinders
Mean annual precipitation--about 2200 mm
Mean annual air temperature--about 4 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 over fragmental or cindery, amorphic Humic Vitricryands

TYPICAL PEDON: Simsbutte gravelly ashy sandy loam on a 55-percent, forested cinder cone at an elevation of 1177 m

Oi--0 to 3 cm; slightly decomposed plant material; abrupt smooth boundary

Oe--3 to 7 cm; moderately decomposed plant material; abrupt wavy boundary

A--7 to 38 cm; gravelly ashy sandy loam, brown (10YR 5/3) dry, dark brown (10YR 3/3) moist; weak fine subangular blocky structure; soft, very friable, nonsticky, nonplastic; common very fine through very coarse roots; many very fine irregular pores; 25 percent cinder gravel; moderately acid (pH 5.8); clear smooth boundary

AC--38 to 58 cm; very gravelly ashy loamy sand, yellowish brown (10YR 5/4) dry, dark brown (10YR 3/3) moist; weak very fine subangular blocky structure; soft, very friable, nonsticky, nonplastic; common medium, coarse, very fine and few fine roots; many very fine irregular pores; 45 percent cinder gravel; slightly acid (pH 6.2); clear smooth boundary

C--58 to 150 cm; gravel, dark grayish brown (10YR 4/2) dry, very dark grayish brown (10YR 3/2) moist; single grain; loose, nonsticky, nonplastic; few medium and very fine roots; many fine interstitial pores; 90 percent cinder gravel and 2 percent scoria cobbles; slightly acid (pH 6.2)

TYPE LOCATION: Linn County, Oregon, on the north flank of Little Nash Crater, about 8 km west of Santiam Pass; 650 m north and 700 m west of the southeast corner of section 15, T. 13 S., R. 7 E., Willamette Meridian; Santiam Junction, Oregon, U.S. Geological Survey quadrangle; latitude 44.438211, longitude -121.957256, datum WGS 84 (coordinates determined with a GPS)

RANGE IN CHARACTERISTICS:
Mean annual soil temperature--3 to 8 degrees C
Soil moisture control section--usually moist but dry in all parts for less than 45 consecutive days following summer solstice in normal years
Thickness of umbric epipedon--25 to 75 cm
Thickness of andic soil properties--25 to 75 cm
Depth to strongly contrasting particle-size class--25 to 75 cm below the mineral soil surface
Reaction--pH 5.6 to 6.5
Hue--10YR, 7.5YR

Particle-size control section (upper part, weighted average)
*Clay content--0 to 5 percent
*Total rock fragment content--35 to 55 percent
*Ammonium oxalate extractable Al plus 1/2 Fe--1.0 to 3.0 percent
*Particles 0.02 to 2.0 mm diameter--greater than 30 percent of the fine-earth fraction
*Volcanic glass content in 0.02 to 2.0-mm fraction--60 to 90 percent
*Phosphate retention--50 to 85 percent
*1500 kPa water (air-dried samples)--5 to 12 percent
*1/3-bar bulk density--0.6 to 0.9 g/cm3

O horizons
*Composition--slightly to moderately decomposed plant material
*Thickness--0 to 10 cm

A and AC horizons
*Value--2 to 3 moist, 3 to 5 dry
*Chroma--2 or 3 moist, 2 to 4 dry
*Fine-earth texture--ashy sandy loam, ashy loamy sand, ashy fine sandy loam
*Clay content--0 to 5 percent
*Total fragment content--15 to 55 percent
*Gravel content (cinders)--15 to 55 percent
*Cobble content (scoria)--0 to 10 percent
*Thickness--25 to 75 cm
*Organic carbon content--1 to 4 percent

C horizon
*Value--3 or 4 moist, 3 to 5 dry
*Chroma--1 to 4 moist or dry
*Total fragment content--90 to 100 percent
*Gravel content (cinders)--85 to 100 percent
*Cobble content (scoria)--0 to 15 percent

COMPETING SERIES: None

GEOGRAPHIC SETTING:
Elevation--1150 to 2150 m
Climate--cold, wet winters; mild, dry summers
Mean annual precipitation--1800 to 2600 mm
Mean annual air temperature--2 to 7 degrees C
Frost-free period--30 to 105 days

GEOGRAPHICALLY ASSOCIATED SOILS:
Lavaflat--ashy particle-size family, fragments are mainly vesicular basalt cobbles and stones; located on lava flows
Kweo--soil moisture control section is dry in all parts for 45 to 90 consecutive days following summer solstice in normal years (xeric soil moisture regime); located on cinder cones east of the Cascade Mountain crest
Littlenash--soil moisture control section is dry in all parts for 45 to 60 consecutive days following summer solstice in normal years (xeric soil moisture regime), frigid soil temperature regime; located on cinder cones

DRAINAGE AND SATURATED HYDRAULIC CONDUCTIVITY:
Drainage class--somewhat excessively drained
Flooding--none
Ponding--none
Saturated hydraulic conductivity (Ksat)--high or very high in the upper part and very high in the lower part

USE AND VEGETATION:
Use--water supply, wildlife habitat, recreation; source for road abrasive material
Potential natural vegetation--Pacific silver fir, western hemlock, grand fir, mountain hemlock, subalpine fir, lodgepole pine, whitebark pine, Cascade barberry, grouse whortleberry, pinemat manzanita, common juniper, starry false lily of the valley, Hitchcock's smooth woodrush

DISTRIBUTION AND EXTENT: High Cascade Mountains, Oregon; MLRA 3; small extent

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

SERIES PROPOSED: Willamette National Forest, Linn County, Oregon; name from volcanic butte in eastern Lane County

REMARKS:
Diagnostic horizons and other features in this pedon
*Particle-size control section--zone from 7 to 107 cm
*Umbric epipedon--zone from 7 to 58 cm
*Andic soil properties--zone from 7 to 58 cm
*Volcanic glass--zone from 7 to 58 cm
*Depth to strongly contrasting particle-size class--51 cm below the mineral soil surface

02/2024--the upper part of the particle-size control section meets criteria #3 for andic soil properties in the 13th edition of Keys to Soil Taxonomy. Some pedons also meet criteria #2 in the umbric epipedon.

ADDITIONAL DATA: Type location user site ID--2022OR043762

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National Cooperative Soil Survey
U.S.A.