LOCATION LITTLENASH              OR

Tentative Series
DCR
02/2025

LITTLENASH SERIES

Landscape--High Cascade volcanic fields
Landform--cinder cones
Slope--30 to 60 percent
Parent material--volcanic ash over cinders
Mean annual precipitation--about 2000 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-skeletal over fragmental or cindery, amorphic, frigid Humic Vitrixerands

TYPICAL PEDON: Littlenash very gravelly ashy sandy loam on a 60-percent, forested cinder cone at an elevation of 1177 m

Oi--0 to 5 cm; slightly decomposed plant material, clear wavy boundary

A1--5 to 30 cm; very 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; low; common very fine through very coarse roots; common very fine dendritic tubular pores; 45 percent cinder gravel; moderately acid (pH 5.8); clear wavy boundary

A2--30 to 62 cm; very 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 coarse roots; many very fine irregular pores; 45 percent cinder gravel; slightly acid (pH 6.2); clear wavy boundary

C--62 to 150 cm; gravel, very dark gray (10YR 3/1) dry, very dark grayish brown (10YR 3/2) moist; single grain; loose, nonsticky, nonplastic; common coarse roots at top of horizon and few very fine roots throughout; 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 south flank of Little Nash Crater, about 8 km west of Santiam Pass; 180 m north and 630 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 44.434035, longitude -121.956327, datum WGS 84 (coordinates determined with a GPS)

RANGE IN CHARACTERISTICS:
Mean annual soil temperature--6 to 8 degrees C
Soil moisture control section--dry in all parts for 45 to 90 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 fragments--35 to 60 percent
*Ammonium oxalate extractable Al plus 1/2 Fe--1.0 to 2.0 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--25 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 decomposed plant material
*Thickness--0 to 8 cm

A 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 fine sandy loam, ashy loamy sand
*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
*Organic carbon content--1 to 3 percent
*Thickness--25 to 75 cm

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--790 to 1275 m
Climate--cool, wet winters; warm, dry summers
Mean annual precipitation--1800 to 2200 mm
Mean annual air temperature--5 to 7 degrees C
Frost-free period--75 to 135 days

GEOGRAPHICALLY ASSOCIATED SOILS:
Breitenbush--ashy-skeletal 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
Simsbutte--cryic soil temperature regime, soil moisture control section is dry in all parts for less than 45 consecutive days following summer solstice in normal years (udic soil moisture 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--Douglas-fir, grand fir, western white pine, giant chinquapin, greenleaf manzanita, snowbrush ceanothus, oceanspray

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 Little Nash Crater in eastern Linn County

REMARKS:
Diagnostic horizons and other features in this pedon
*Particle-size control section--zone from 5 to 105 cm
*Umbric epipedon--zone from 5 to 62 cm
*Andic soil properties--zone from 5 to 62 cm
*Volcanic glass--zone from 5 to 62 cm
*Depth strongly contrasting particle-size class--57 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.

ADDITIONAL DATA: Type location user site ID--2022OR043761

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National Cooperative Soil Survey
U.S.A.