LOCATION MONUMENTROCK            OR

Established Series
IRD. RJO/JLW/DAL/KMS
02/2019

MONUMENTROCK SERIES

Landscape--mountains, plateaus
Landform--mountain slopes, plateaus
Slope--15 to 90 percent
Parent material--thin mantle of volcanic ash over colluvium derived from andesite or basalt
Mean annual precipitation--about 1070 mm
Mean annual air temperature--about 2 degrees C
Depth class--deep to lithic contact
Drainage class--well drained
Soil moisture regime--udic
Soil temperature regime--cryic
Soil moisture subclass--typic

TAXONOMIC CLASS: Loamy-skeletal, isotic Andic Haplocryepts

TYPICAL PEDON: Monumentrock gravelly ashy silt loam in an area of woodland, on a 45-percent, north-facing slope at an elevation of 2012 m

Oi--0 to 3 cm; slightly decomposed needles and twigs

A--3 to 8 cm; cobbly ashy silt loam, grayish brown (10YR 5/2) dry, dark brown (7.5YR 3/2) moist; weak very fine subangular blocky structure; soft, very friable, nonsticky and nonplastic; common very fine and many fine roots; 10 percent gravel and 5 percent cobbles; slightly acid (pH 6.5); clear smooth boundary

Bw--8 to 33 cm; cobbly ashy silt loam, brown (10YR 5/3) dry, brown (10YR 4/3) moist; weak medium and fine subangular blocky structure parting to very fine subangular blocky; soft, very friable, nonsticky and nonplastic; many very fine and medium and common coarse roots; common fine irregular pores; 15 percent gravel, 10 percent cobbles, and 5 percent stones; neutral (pH 7.0); clear wavy boundary

2EBb--33 to 74 cm; very stony silt loam, pale brown (10YR 6/3) dry, brown (7.5YR 5/4) moist; weak medium and fine subangular blocky structure; soft, very friable, nonsticky and nonplastic; many fine and common medium and coarse roots; few fine irregular pores; 25 percent gravel, 10 percent cobbles, and 10 percent stones; neutral (pH 7.0); gradual smooth boundary

2Bwb1--74 to 99 cm; extremely stony sandy loam, pale brown (10YR 6/3) dry, brown (7.5YR 4/4) moist; weak fine and very fine subangular blocky structure; soft, very friable, nonsticky and nonplastic; common fine and few medium and coarse roots; few fine irregular pores; 25 percent gravel, 20 percent cobbles, and 20 percent stones; neutral (pH 7.0); clear smooth boundary

2Bwb2--99 to 117 cm; extremely stony sandy loam, pale brown (10YR 6/3) dry, brown (7.5YR 4/4) moist; weak medium subangular blocky structure; soft, friable, nonsticky and nonplastic; few fine and medium roots; few fine tubular pores; 30 percent gravel, 20 percent cobbles, and 20 percent stones; neutral (pH 7.0); abrupt irregular boundary

2R--117 cm; andesitic basalt

TYPE LOCATION: Baker County, Oregon, about 485 m west and 544 m north of the southeast corner of section 9, T. 13 S., R. 35.5 E.; latitude 44.4515150, longitude -118.4195740, datum WGS 84 (coordinates and PLSS details estimated from point on hard copy map)

RANGE IN CHARACTERISTICS:
Mean annual soil temperature--about 2 to 3 degrees C
Mean summer soil temperature--about 5 to 7 degrees C
Mean winter soil temperature--about -2 to 2 degrees C
Soil moisture--dry 30 to 45 consecutive days in summer
Depth to lithic contact--100 to 150 cm
Thickness of ash-influenced layers--25 to 35 cm

Estimated properties of layers influenced by volcanic ash
*Ammonium oxalate extractable Al + 1/2 Fe--1.5 to 3.0 percent
*0.02- to 2.0-mm fraction--40 to 60 percent
*Glass content in 0.02- to 2.0-mm fraction--60 to 90 percent
*1/3-bar bulk density--0.70 to 1.00 g/cm3
*Phosphate retention--60 to 90 percent
*15-bar water retention--5 to 12 percent (dried samples)
*8 x Si plus 2 x Fe--5 to 12 percent

Particle-size control section
*Clay content--5 to 15 percent
*Total rock fragment content--50 to 75 percent

A horizon
Moist color--7.5YR 3/2, 10YR 3/2, 10YR 3/3
Dry color--10YR 4/3, 10YR 5/2, 10YR 5/3, 10YR 6/4
Fine-earth texture--ashy silt loam
Clay content--4 to 7 percent
Sand content--30 to 45 percent
Organic matter content--2 to 6 percent
Total rock fragment content--20 to 30 percent
Gravel content--10 to 20 percent
Cobble content--0 to 10 percent
Stone content--0 to 5 percent
Reaction--6.1 to 7.3
Base saturation (NH4OAc)--15 to 30 percent
Thickness--3 to 15 cm

Bw horizon
Moist color--10YR 4/3, 10YR 4/4, 10YR 5/4
Dry color--10YR 5/3, 10YR 5/4, 10YR 6/3, 10YR 7/4
Fine-earth texture--ashy silt loam
Clay content--4 to 7 percent
Sand content--35 to 45 percent
Organic matter content--1 to 3 percent
Total rock fragment content--20 to 30 percent
Gravel content--15 to 25 percent
Cobble content--0 to 10 percent
Stone content--0 to 5 percent
Reaction--6.1 to 7.3
Base saturation (NH4OAc)--25 to 45 percent
Thickness--15 to 33 cm

2Eb horizon, and 2EBb horizon (where present)
Moist color--7.5YR 5/4, 10YR 3/4, 10YR 4/3, 10YR 5/4
Dry color--10YR 6/3, 10YR 6/4
Fine-earth texture--loam, sandy loam
Clay content--5 to 11 percent
Sand content--40 to 65 percent
Organic matter content--1.5 to 3.5 percent
Total rock fragment content--45 to 60 percent
Gravel content--25 to 40 percent
Cobble content--5 to 15 percent
Stone content--0 to 10 percent
Reaction--5.6 to 7.3
Base saturation (NH4OAc)--40 to 60 percent
Thickness--10 to 41 cm

2Bwb horizon, and 2BCb horizon (where present)
Moist color--7.5YR 4/4, 10YR 4/3, 10YR 5/3, 10YR 5/4
Dry color--10YR 6/2, 10YR 6/3
Fine-earth texture--sandy loam
Clay content--5 to 12 percent
Sand content--55 to 85 percent
Organic matter content--0.5 to 2.0 percent
Total rock fragment content--45 to 85 percent
Gravel content--25 to 60 percent
Cobble content--5 to 30 percent
Stone content--0 to 20 percent
Reaction--5.6 to 7.3
Base saturation (NH4OAc)--55 to 75 percent
Thickness--40 to 100 cm

COMPETING SERIES:
Bearpawmeadow--50 to 100 cm (moderately deep) to a lithic contact (andesite, basalt)
Bordengulch--50 to 100 cm (moderately deep) to a lithic contact (argillite, sandstone)
Marblepoint--no lithic contact within a depth of more than 150 cm; formed in a mantle of volcanic ash over material derived from till; rock fragments dominantly subrounded or rounded cobbles and stones
Risingwolf, Vandamine--no lithic contact within a depth of more than 150 cm

GEOGRAPHIC SETTING:
Elevation--1750 to 2340 m
Climate--cold, wet winters; cool, moist summers
Mean annual precipitation--680 to 1610 mm
Mean annual air temperature--0 to 4 degrees C
Frost-free period--15 to 60 days

GEOGRAPHICALLY ASSOCIATED SOILS:
Bearpawmeadow--on shoulders and mid backslopes of colluvial mountain slopes; 50 to 100 cm (moderately deep) to lithic contact (andesite, basalt)
Burgerbutte--on backslopes to ridges of glacial scoured or colluvial mountain slopes; 35 to 50 cm (shallow) to a lithic contact
Lackeyshole--on concave mountain side slopes; 100 to 150 cm (deep) to a lithic contact (andesite, basalt); ash mantle more than 36 cm thick
Mountemily--on planar to concave, mid to lower mountain slopes; no lithic contact within a depth of more than 150 cm; ash mantle more than 36 cm thick
Troutmeadows--on benches and ridges; 50 to 100 cm (moderately deep) to a lithic contact (basalt); ash mantle more than 36 cm thick

DRAINAGE AND PERMEABILITY:
Saturation during normal years--none
Flooding--none
Ponding--none
Saturated hydraulic conductivity (Ksat)--moderately high over high

USE AND VEGETATION:
Use--watershed, wildlife habitat, timber production, livestock grazing, recreation
Potential native vegetation-- subalpine fir, Engelmann spruce, lodgepole pine, Douglas-fir, western larch, grand fir, grouse huckleberry, pink mountain-heather, heartleaf arnica, pinegrass, violet, prince's pine, elk sedge, Virginia strawberry, myrtle pachystima, pyrola, big huckleberry, Ross' sedge, sweetcicely, darkwoods violet

DISTRIBUTION AND EXTENT: Blue Mountains of northeastern Oregon; MLRA 10; small extent

SOIL SURVEY REGIONAL OFFICE (SSRO) RESPONSIBLE: Portland, Oregon

SERIES ESTABLISHED: Wallowa-Whitman National Forest, Oregon 2018

REMARKS:
Diagnostic horizons and other features recognized in this pedon
*Ochric epipedon
*Upper cambic horizon--zone from 8 to 33 cm
*Buried cambic horizon--zone from 74 to 117 cm
*Volcanic glass--zone from 3 to 33 cm
*Andic soil properties--zone from 3 to 33 cm
*Particle-size control section--zone from 28 to 103 cm

ADDITIONAL DATA:
Laboratory data--National Soil Survey Laboratory pedon number 92OR063004; 48 percent base saturation (NH4OAc) between depths of 48 and 75 cm.

The Monumentrock series is similar to the Mountemily series that has a thicker ash mantle and base saturation of 75 to 90 percent in the lower part.

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National Cooperative Soil Survey
U.S.A.