LOCATION DOHERT ORTentative Series
TAXONOMIC CLASS: Ashy over loamy, amorphic over isotic, frigid Alfic Vitrixerands
TYPICAL PEDON: Dohert ashy silt loam, woodland, on a 30 percent south-facing slope at an elevation of 4,840 feet. (Colors are for moist soil unless otherwise noted.)
Oi--0 to 1 inches; needles and leaves
A--1 to 4 inches; dark brown (10YR 3/3) ashy silt loam, dark grayish brown (10YR 4/2) dry; weak fine granular structure; soft, very friable, nonsticky and nonplastic; many fine roots; few fine irregular pores; moderately acid (pH 6.0); gradual smooth boundary. (3 to 6 inches thick)
Bw1--4 to 13 inches; dark yellowish brown (10YR 4/4) ashy silt loam, very pale brown (10YR 7/3) dry; weak medium and fine subangular blocky structure; soft, very friable, nonsticky and nonplastic; many fine and common medium roots; few fine irregular pores; slightly acid (pH 6.5); gradual smooth boundary.
Bw2--13 to 17 inches; dark yellowish brown (10YR 4/4) ashy silt loam, very pale brown (10YR 7/4) dry; weak medium and fine subangular blocky structure; soft, very friable, nonsticky and nonplastic; common fine and medium roots; few fine irregular pores; slightly acid (pH 6.5); abrupt wavy boundary. (combined thickness of the Bw horizons is 13 to 24 inches)
2AEb--17 to 25 inches; brown (10YR 5/3) loam, light gray (10YR 7/2) dry; moderate medium and fine subangular blocky structure; slightly hard, very friable, moderately sticky and slightly plastic; common fine and medium roots; few fine irregular and common fine tubular pores; 10 percent gravel; slightly acid (pH 6.5); clear smooth boundary.
2BEb--25 to 36 inches; grayish brown (2.5Y 5/2) gravelly silt loam, light gray (2.5Y 7/2) dry; moderate to strong medium and fine subangular blocky structure; hard, friable, slightly sticky and moderately plastic; few fine and medium roots; few fine irregular and common fine tubular pores; 15 percent gravel; slightly acid (pH 6.5); clear irregular boundary. (combined thickness of the 2AEb and 2BEb horizons is 15 to 20 inches)
2Btb1--36 to 41 inches; strong brown (7.5YR 4/6) gravelly sandy clay loam, very pale brown (10YR 7/4) dry; strong medium and fine angular blocky structure; hard, friable, moderately sticky and moderately plastic; common distinct clay films on ped faces; few fine roots; few fine vesicular and tubular pores; 30 percent gravel; slightly acid (pH 6.5); clear irregular boundary. (3 to 7 inches thick)
2Btb2--41 to 43 inches; yellowish red (5YR 4/6) very gravelly sandy clay, yellowish red (5YR 5/6) dry; slightly hard, firm, very sticky and very plastic; continuous prominent clay films on ped faces and organoargillans on mineral grains; 55 percent gravel; slightly acid (pH 6.5); clear irregular boundary. (2 to 20 inches thick)
2R--43 inches; fractured metamorphic bedrock
TYPE LOCATION: Union County, Oregon
Section 24 (SE 1/4, NE 1/4, NE 1/4), T. 6 S., R. 37 E.
Latitude: 45 degrees, 7 minutes, 31 seconds N.
Longitude: 118 degrees, 21 minutes, 7 seconds W.
UTM Coordinates: Zone: 11; Northing: 4,997,756.5; Easting: 393,678.6
USGS Quadrangle: Tucker Flat
RANGE IN CHARACTERISTICS:
Soil Temperature: frigid regime
Mean Annual Soil Temperature: 46 to 51 degrees F
Mean Summer Soil Temperature: 56 to 64 degrees F
Mean Winter Soil Temperature: 35 to 39 degrees F
Soil Moisture: xeric regime; dry 45 to 60 days in summer
Particle-size Control Section: mineral soil surface to 40 inches below mineral soil surface
Upper part (ashy): 16 to 30 inches thick
Clay content (weighted average): 2 to 8 percent
Rock fragment content (weighted average): 0 percent
Lower part (loamy): 10 to 24 inches thick
Clay content (weighted average): 19 to 27 percent
Rock fragment content (weighted average): 5 to 20 percent
Rock fragment shape: angular
Diagnostic Horizons and Features:
andic soil properties: upper boundary at the mineral surface; 16 to 30 inches thick
Al+1/2Fe(aox): 1.0 to 2.5 percent
bulk density: 0.65 to 1.0 g/cc
P retention: 40 to 90 percent
0.02-2.0 mm fraction: 40 to 60 percent of fine earth
glass content in the 0.02-2.0mm fraction: 60 to 90 percent
water content at 1500 kPa (air dried): 5 to 12 percent
8Si + 2Fe (aox): 5 to 12 percent
8Si - 2Fe (aox): 4 to 8 percent
ochric epipedon: 3 to 6 inches thick
cambic horizon: 13 to 24 inches thick
argillic horizon: 8 to 27 inches thick
lithic contact, depth: 40 to 60 inches
Major Horizons:
A Horizon:
color, moist: 10YR 3/3
color, dry: 10YR 4/2, 5/2, 5/3, 6/3
texture: ASHY-SIL
clay content: 1 to 5 percent
rock fragment content: 0 percent
reaction: strongly acid to slightly acid; pH: 5.1 to 6.5
Bw Horizon; may include Bw2 horizon:
color, moist: 10YR 3/6, 4/3, 4/4, 5/3
color, dry: 10YR 6/2, 6/3, 6/4, 7/3, 7/4
texture: ASHY-SIL
clay content: 2 to 5 percent
rock fragment content: 0 percent
reaction: strongly acid to slightly acid; pH: 5.1 to 6.5
2Eb Horizon; may include 2AE, 2BE horizons:
color, moist: 2.5Y 5/2; 10YR 4/3, 5/3
color, dry: 2.5Y 7/2; 10YR 6/3, 7/2
texture: SIL, L
clay content: 15 to 20 percent
rock fragment content: 5 to 15 percent
gravel: 5 to 15 percent
reaction: slightly acid; pH: 6.1 to 6.5
2Btb1 Horizon:
color, moist: 2.5Y 4/3[r1]; 7.5YR 4/6; 10YR 4/3, 4/4
color, dry: 2.5Y 6/2; [r2]10YR 5/4, 7/4
texture: C, GR-C, GR-SCL, CL
clay content: 25 to 45 percent
rock fragment content: 3 to 30 percent
gravel: 5 to 30 percent
reaction: moderately acid to neutral; pH: 5.6 to 7.3
2Btb2 Horizon; and C horizon if present:
color, moist: 5Y 3/2, 4/3; 5YR [r3]4/6; 10YR 4/3
color, dry: 5Y 4/3, 5/3; 5YR 5/6; [r4]10YR 5/3
texture: GR-SIL, GR-CL, GRV-SC
clay content: 20 to 35 percent
rock fragment content: 30 to 60 percent
gravel: 30 to 60 percent
cobbles: 0 to 3 percent
reaction: moderately acid to neutral; pH: 5.6 to 7.3
COMPETING SERIES: These are the Tolo and Torchsprings (T) series. The Brusher and Smiling series have similar classification with glassy mineralogy.
Tolo soils - typically more than 60 inches deep to basalt bedrock; ashy part of pscs has 2 to 8 percent clay; loamy part of the pscs has 0 to 35 percent subangular rock fragments of basalt origin; lower part of series control section below 40 inches contains up to 50 percent subangular cobbles and gravel of basalt origin
Torchspring soils - more than 60 inches deep to bedrock; ashy part of pscs has 4 to 8 percent clay; loamy part of pscs has 5 to 30 percent rounded and subrounded rock fragments of glacial till origin.
Brusher soils - more than 60 inches deep to weathered granitic bedrock; ashy part of pscs ranges to Ashy-L, or Ashy-FSL and has glassy mineralogy; loamy part of pscs has 0 to 25 percent subangular rock fragments of granitic or porphyritic origin; has 2E/B and 2B/E horizons.
Smiling soils - ashy part of pscs has Ashy-SL and glassy mineralogy; loamy part of pscs has 5 to 35 percent subangular rock fragments of basalt or andesite origin.
GEOGRAPHIC SETTING:
Landform: benches and toeslopes of mountains
Slope gradient: 15 to 30 percent
Parent material: volcanic ash over, loess and colluvium over residuum
Lithology: Mazama ash overlying argillite or metasedimentary rocks
Elevation: 2,000 to 5,000 feet
Climate: cold, wet winters and warm, dry summers
Mean annual precipitation: 12 to 15 inches[r5]
Mean annual air temperature: 44 to 49 degrees F
Frost-free period: 60 to 200 days
GEOGRAPHICALLY ASSOCIATED SOILS:
Slaughterhouse(T): occur on steeper backslopes and have greater than 35 percent rock fragments and 11 to 27 percent clay in lower part of pscs
DRAINAGE AND PERMEABILITY:
Drainage: well drained
Permeability: moderately rapid
USE AND VEGETATION:
Use: watershed, wildlife habitat, timber production, livestock grazing and recreation
Native vegetation: grand fir, Douglas fir, western larch, ponderosa pine, lodgepole pine, bearberry, baldhip rose, common snowberry, big huckleberry, low Oregongrape, woods strawberry, blueleaf strawberry, common yarrow, white hawkweed, small cleavers, heartleaf arnica, Idaho fescue, pinegrass, mountain brome, western fescue and elk sedge
DISTRIBUTION AND EXTENT:
MLRA-- E43c, Blue Mountains
Distribution: Blue Mountains of northeastern Oregon
Extent: small
MLRA OFFICE RESPONSIBLE: Portland, Oregon
SERIES PROPOSED: Union County, Oregon; 2004. The name is from a spring on the Sullivan Gulch quadrangle.
REMARKS: Diagnostic horizons and features recognized in this pedon are:
ochric epipedon: 1 to 4 inches; A
cambic horizon: 4 to 17 inches; Bw1, Bw2
argillic horizon: 36 to 43 inches; 2Btb1, 2Btb2
particle-size control section:
ashy part: 1 to 17 inches; A, Bw1, Bw2
loamy part: 17 to 41 inches; 2AEb, 2BEb, 2Btb1
Ecological site: Dominant: ABGR/CARU; may include ABGR/CAGE
Notes on Series Concept:
07/04 - For this series concept, soils formed from both argillite and metasediments were combined. It is this combination of parent materials which gives rise to the highly variable soil color, especially true for soils formed in metasediments.
07/04- This soil is currently recognized within the Blue Mt. soil survey in a 12-15 inch mean annual precipitation zone, having 45 to 60 consecutive days dry following the summer solstice, and having a dry grand fir habitat type. This precipitation range is much lower than what is typically correlated to a dry grand fir xeric zone and is believed to be derived from effective moisture supplied by its landscape position in addition to a thick ash mantle. As this series is mapped, continued supporting documentation on the mean annual ppt. and corresponding plant association is highly recommended.