LOCATION PLAIDEN OR
Tentative Series
SCW/KLM/MPR
02/2025
PLAIDEN SERIES
Landscape--plateaus
Landform--fan remnants
Slope--2 to 50 percent
Parent Material--colluvium and residuum derived from Rattlesnake Formation fanglomerate with a minor influence of volcanic ash in the surface
Mean annual precipitation--380 mm
Mean annual air temperature--8 degrees C
Depth class--moderately deep
Drainage class--well drained
Soil moisture regime--xeric
Soil temperature regime--mesic
Soil moisture subclass--typic
TAXONOMIC CLASS: Fine, smectitic, mesic Vertic Palexerolls
TYPICAL PEDON: Plaiden very gravelly ashy sandy clay loam, rangeland, on a 45 percent, west facing slope at an elevation of 990 m (When described on September 30, 2015, the soil was dry throughout.)
A--0 to 3 cm; very gravelly ashy sandy clay loam, brown (10YR 5/3) dry, dark brown (10YR 3/3) moist,; moderate medium subangular blocky structure; slightly hard, friable, slightly sticky and slightly plastic; few fine and many very fine roots; few fine and common very fine irregular pores; 40 percent gravel; moderately alkaline (pH 8.0); abrupt smooth boundary (3 to 8 cm thick)
2Bt1--3 to 33 cm; clay, brown (10YR 5/3) dry, dark brown (10YR 3/3) moist; strong coarse prismatic structure; very hard, very friable, very sticky and very plastic; few fine and common very fine roots; few fine and very fine tubular pores; many prominent clay films on ped faces; moderately alkaline (pH 8.0); gradual wavy boundary
2Bt2--33 to 43 cm; clay, brown (7.5YR 4/3) dry, dark brown (7.5YR 3/3) moist; moderate medium prismatic structure; very hard, very firm, very sticky and very plastic; few very fine roots; few very fine tubular pores; many distinct clay films on ped faces; moderately alkaline (pH 8.1); gradual wavy boundary
2Bt3--43 to 56 cm; clay, pale brown (10YR 6/3) dry, brown (10YR 5/3) moist; moderate medium prismatic structure; very hard, very firm, very sticky and very plastic; many distinct clay films on ped faces; moderately alkaline (pH 8.1); clear wavy boundary
2Bt4--56 to 86 cm; gravelly clay, brown (7.5YR 4/3) moist and dry; moderate coarse angular blocky structure; hard, firm, very sticky and very plastic; 20 percent weathered gravel; many distinct clay films on ped faces; moderately alkaline (pH 8.2)
2Cd--86 cm; densic fanglomerate bedrock that crushes to extremely gravelly loamy sand, brown (7.5YR 4/3) moist and dry; massive; extremely hard, slightly rigid, nonsticky and nonplastic; 65 percent rounded gravel; moderately alkaline (pH 8.0)
TYPE LOCATION: Grant County, Oregon, about 3.6 km south of the town of Mt. Vernon; about 513 m south and 432 m east of the NW corner of section 3, T. 14 S., R. 31 E.
Latitude-- 44.38379
Longitude-- -119.10836
Datum--WGS84 (coordinates determined with a GPS)
RANGE IN CHARACTERISTICS:
Mean annual soil temperature--8 to 11 degrees C
Soil moisture--usually moist, but are dry 70 to 90 consecutive days during the four months following the summer solstice
Depth to densic bedrock--50 to 100 cm
Mollic epipedon--25 to 50 cm thick
Argillic horizon--46 to 102 cm thick
COLE--0.06 to 0.0775
Particle size control section:
Clay content--35 to 55 percent
Total rock fragment content--0 to 25 percent
Rock fragment type--mixed lithologies derived from the Rattlesnake fanglomerate
Volcanic ash surface:
5 to 15 cm thick
Volcanic glass content--20 to 40 percent
Ammonium oxalate Al plus Fe--0.4 to 1.0 percent
A horizon
Value--4 or 5 dry, 2 or 3 moist
Chroma--2 or 3 dry or moist
Fine earth texture--loam, sandy clay loam
Clay content--20 to 30 percent
Sand content--30 to 60 percent
Organic matter--2 to 5 percent
Total rock fragments--15 to 40 percent (gravel)
Reaction--slightly alkaline to moderately alkaline
2Bt horizons
Hue-- 5YR, 7.5YR, 10YR, dry or moist
Value--4 to 6 dry, 3 to 5 moist
Chroma--2 or 3 dry or moist
Fine earth texture--clay loam, or clay
Clay content--35 to 60 percent
Sand content--15 to 45 percent
Organic matter-0.5 to 2.0 percent
Total rock fragments--0 to 25 percent (gravel)
Reaction--slightly alkaline to moderately alkaline
2Cd horizon
Hue-- 5YR, 7.5YR, 10YR, dry or moist
Value--4 to 6 dry, 3 to 5 moist
Chroma--2 or 3 dry or moist
Fine earth texture--loamy sand
Clay content--35 to 55 percent
Fine earth texture--after crushing; loamy sand
Clay content--0 to 10 percent
Sand content--70 to 90 percent
Organic matter--0 percent
Total rock fragments--60 to 90 percent (gravel)
COMPETING SERIES:
Pung--greater than 150 cm to bedrock
Simas--greater than 150 cm to bedrock and have secondary carbonates
Steerlake--100 to 150 cm to duripan
GEOGRAPHIC SETTING:
Elevation--850 to 1220 m
Climate--cool, wet winters and hot, dry summers
Mean annual precipitation--305 to 455 mm
Mean annual air temperature 8 to 10 degrees C
Frost-free period--80 to 120 days
GEOGRAPHICALLY ASSOCIATED SOILS:
Belshaw--greater than 150 cm to restrictive feature; occur on benches and adjacent hillslopes
Grell--average less than 35% clay and more than 35% rock fragments in the control section; occur on very steep south facing slopes
Hack--occur on footslopes and fans; average between 18 and 35% clay in the PSCS
Oliver--occur on benches and fan remnants and are 25 to 50 cm to ultramafic bedrock
Steadison--occur on fan remnants and are less than 25 cm to densic bedrock
Whipsteen--occur on fan remnants and are 25 to 50 cm to densic bedrock
DRAINAGE AND SATURATED HYDRAULIC CONDUCTIVITY:
Drainage--well drained
Saturated hydraulic conductivity (Ksat)--moderately high to high in the ash influenced horizons moderately low in argillic horizons
USE AND VEGETATION:
Use--livestock grazing, wildlife habitat
Vegetation--bluebunch wheatgrass, Idaho fescue, Sandberg bluegrass
DISTRIBUTION AND EXTENT:
East-central Oregon; MLRA 9; small extent
SOIL SURVEY REGIONAL OFFICE (SSRO) RESPONSIBLE: Bozeman, Montana
SERIES PROPOSED:
Grant County, Oregon 2/2016; The name is coined
REMARKS:
Diagnostic horizons and features in this pedon are:
Particle size control section--3 to 53 cm
Mollic epipedon--0 to 43 cm
Volcanic ash influence--meets glass and chemical requirements for Vitrandic properties but is not thick enough for Vitrandic subgroup
Argillic horizon--3 to 86 cm
COLE-0.0765 cm
Densic contact--86 cm
Xeric moisture regime
National Cooperative Soil Survey
U.S.A.