LOCATION LIMBERLOST              OR

Tentative Series
DCR
02/2025

LIMBERLOST SERIES

Landscape--High Cascade volcanic fields
Landform--lava flows
Slope--2 to 15 percent
Parent material--residuum weathered from vesicular basalt mixed with volcanic ash
Mean annual precipitation--about 2000 mm
Mean annual air temperature--about 6.5 degrees C
Depth class--very deep
Drainage class--well drained
Soil moisture regime--udic
Soil temperature regime--frigid
Soil moisture subclass--typic

TAXONOMIC CLASS: Medial-skeletal, amorphic, frigid Humic Udivitrands

TYPICAL PEDON: Limberlost cobbly medial fine sandy loam on an-8 percent, forested slope at an elevation of 870 m

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

A--3 to 20 cm; cobbly medial fine sandy loam, brown (10YR 4/3) dry, very dark grayish brown (10YR 3/2) moist; weak fine subangular blocky structure; soft, very friable, nonsticky, nonplastic; common very fine through coarse roots; common very fine dendritic tubular pores; 10 percent gravel and 10 percent cobbles; moderately acid (pH 5.8); clear wavy boundary

AB--20 to 49 cm; extremely stony medial fine 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 and medium and few fine and coarse roots; common very fine dendritic tubular pores; 20 percent gravel, 15 percent cobbles, and 30 percent stones; moderately acid (pH 5.9); clear wavy boundary

Bw1--49 to 80 cm; very cobbly medial fine sandy loam, brown (10YR 5/3) dry, dark yellowish brown (10YR 3/4) moist; weak fine subangular blocky structure; soft, very friable, nonsticky, nonplastic; common medium and few very fine roots; common very fine dendritic tubular pores; 25 percent gravel, 15 percent cobbles, and 5 percent stones; moderately acid (pH 6.0); gradual wavy boundary

Bw2--80 to 130 cm; very stony medial fine sandy loam, pale brown (10YR 6/3) dry, brown (10YR 4/3) moist; weak fine subangular blocky structure; soft, very friable, nonsticky, nonplastic; few medium and very fine roots; common very fine dendritic tubular pores; 20 percent gravel, 20 percent cobbles, and 15 percent stones; slightly acid (pH 6.1); clear wavy boundary

Bw3--130 to 150 cm; very stony medial fine sandy loam, light brownish gray (10YR 6/2) dry, brown (10YR 4/3) moist; weak fine subangular blocky structure; soft, very friable, nonsticky, nonplastic; few very fine roots; common very fine dendritic tubular pores; 20 percent gravel, 20 percent cobbles, and 15 percent stones; slightly acid (pH 6.2)

TYPE LOCATION: Linn County, Oregon, 3.5 km east of Trail Bridge Reservoir; 230 m south and 660 m east of the northwest corner of section 17, T. 15 S., R. 7 E.; latitude 44.27095, longitude -122.00168, datum WGS 84 (coordinates determined with a GPS)

RANGE IN CHARACTERISTICS:
Mean annual soil temperature--6 to 8 degrees C
Dry days--less than 45 consecutive days following summer solstice
Thickness of umbric epipedon--25 to 75 cm
Thickness of andic soil properties--greater than 150 cm
Clay content--2 to 10 percent
Sand content--50 to 70 percent
Rock fragment roundness, lithology--angular or subangular vesicular basalt

Estimated properties of layers with andic soil properties
*Phosphate retention--greater than 85 percent
*Ammonium oxalate extractable Al + 1/2 Fe--2 to 4 percent
*0.02- to 2.0-mm fraction--greater than 30 percent
*Fine-earth fraction--contains less than 50 percent medium through very coarse sand
*Volcanic glass content in 0.02 to 2.0 mm fraction--60 to 90 percent
*1500 kPa water (air-dried samples)--12 to 15 percent

Particle-size control section (weighted average)
*Clay content--2 to 10 percent
O horizons
*Composition--slightly to moderately decomposed plant material
*Combined thickness--0 to 10 cm

A horizons
*Value--2 or 3 moist, 4 or 5 dry
*Chroma--2 or 3 moist and dry
*Fine-earth texture--medial fine sandy loam, medial sandy loam
*Total fragment content--15 to 60 percent
*Gravel content--0 to 15 percent
*Cobble content--5 to 35 percent
*Stone content--0 to 15 percent
*Pumice paragravel content--0 to 5 percent
*Thickness--15 to 50 cm

AB horizon
*Value--3 or 4 moist, 4 to 6 dry
*Chroma--3 or 4 moist and dry
*Fine-earth texture--medial fine sandy loam, medial sandy loam
*Total fragment content--35 to 80 percent
*Gravel content--10 to 30 percent
*Cobble content--10 to 35 percent
*Stone content--0 to 35 percent
*Pumice paragravel content--0 to 5 percent
*Thickness--15 to 40 cm

Bw horizons
*Value--4 or 5 moist, 5 or 6 dry
*Chroma--3 or 4 moist or dry
*Fine-earth texture--medial fine sandy loam, medial loam
*Total fragment content--35 to 80 percent
*Gravel content--5 to 30 percent
*Cobble content--10 to 35 percent
*Stone content--5 to 35 percent
*Pumice paragravel content--0 to 5 percent
*Reaction--pH 5.6 to 6.5

COMPETING SERIES: None

GEOGRAPHIC SETTING:
Elevation--790 to 1175 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:
Potatohill--averages less than 35 percent rock fragments in the particle-size control section; located on concave positions on lava flows
Proxy--densic contact between 100 and 150 cm; located on glaciated mountains and lateral moraines

DRAINAGE AND SATURATED HYDRAULIC CONDUCTIVITY:
Drainage class--well drained
Saturation in normal years--none within profile
Flooding--none
Ponding--none
Saturated hydraulic conductivity (Ksat)--high or very high

USE AND VEGETATION:
Use--watershed, recreation, wildlife habitat, timber production
Potential natural vegetation--Douglas-fir, western white pine, western hemlock, grand fir, vine maple, beaked hazelnut; Cascade barberry, snowberry, and sweet after death; commonly supports a grand fir/dwarf Oregon grape (CWS522) plant association (Field Guide to the Forested Plant Associations of the Westside Central Cascades of Northwest Oregon)

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; named for campground along the McKenzie River

REMARKS:
Diagnostic horizons and features recognized in this pedon
*Particle-size control section--zone from 3 to 103 cm
*Umbric epipedon--zone from 3 to 49 cm
*Cambic horizon--zone from 49 to 150 cm
*Andic soil properties--zone from 3 to 150 cm
*Volcanic glass--zone from 3 to 150 cm

11/2022--meets criteria #3 for andic soil properties, in the 13th edition of Keys to Soil Taxonomy

ADDITIONAL DATA: Type location user pedon ID--2022OR043823

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National Cooperative Soil Survey
U.S.A.