LOCATION YIKWIL WA
Established Series
Rev. PNP/KDPL/SBC
09/2019
YIKWIL SERIES
Landscape--mountains, plateaus
Landform--mountain slopes, benches
Slope--0 to 60 percent
Parent material--volcanic ash over colluvium and residuum derived from basalt
Mean annual precipitation--about 1000 mm
Mean annual air temperature--about 6 degrees C
Depth class--very deep
Drainage class--well drained
Soil moisture regime--udic
Soil temperature regime--frigid
Soil moisture subclass--typic
TAXONOMIC CLASS: Ashy over loamy-skeletal, mixed over isotic, frigid Alfic Udivitrands
TYPICAL PEDON: Yikwil ashy sandy loam in an area of forestland, on a 6-percent, southeast-facing plateau at an elevation of 1300 m (All textures are apparent field textures.)
Oi--0 to 3 cm; slightly decomposed needles, cones, and twigs mixed with a small amount of 1980 Mount St. Helens ash
A--3 to 28 cm; ashy sandy loam, brown (10YR 4/3) dry, dark brown (7.5YR 3/2) moist; weak fine granular structure; soft, very friable, nonsticky and nonplastic; weakly smeary; many very fine and fine and common medium and coarse roots; common fine irregular pores; 5 percent gravel; slightly acid (pH 6.5); clear smooth boundary
Bw--28 to 86 cm; ashy sandy loam, brown (7.5YR 4/4) dry, dark brown (7.5YR 3/4) moist; weak fine subangular blocky structure; soft, very friable, nonsticky and nonplastic; weakly smeary; few very fine and common fine, medium, and coarse roots; common fine irregular pores; 5 percent cobbles and 5 percent stones; slightly acid (pH 6.3); abrupt smooth boundary
2Bt1--86 to 109 cm; very stony loam, brown (10YR 5/3) dry, dark brown (10YR 3/3) moist; weak medium subangular blocky structure; slightly hard, friable, slightly sticky and nonplastic; common fine, medium, and coarse roots; common very fine and few fine tubular pores; common distinct clay films on faces of peds and in pores; 5 percent gravel, 15 percent cobbles, and 20 percent stones; slightly acid (pH 6.1); clear smooth boundary
2Bt2--109 to 160 cm; very stony loam, yellowish brown (10YR 5/4) dry, dark yellowish brown (10YR 3/4) moist; weak coarse subangular blocky structure; slightly hard, friable, moderately sticky and slightly plastic; few fine and medium roots; few fine and medium tubular pores; common distinct clay films on faces of peds and lining pores; 10 percent gravel, 10 percent cobbles, 25 percent stones, and 10 to 15 percent soft basalt paragravel; moderately acid (pH 5.6)
TYPE LOCATION: Yakama Nation, Yakima County, Washington, about 640 m south and 610 m west of the northeast corner of section 16, T. 9 N., R. 13 E.; latitude 46.2665100, longitude -121.1961822, datum WGS 84 (coordinates estimated from section, township, and range)
RANGE IN CHARACTERISTICS:
Mean annual soil temperature at a depth of 50 cm--7 to 8 degrees C
Moisture control section--usually moist, but dry in all parts 30 to 45 consecutive days following summer solstice
Thickness of umbric epipedon--25 to 55 cm
Lower part of particle-size control section--argillic horizon; 18 to 30 percent clay; 35 to 65 percent rock fragments; 0 to 35 percent soft basalt pararock fragments
Volcanic ash mantle
*Thickness--65 to 95 cm
*Moist bulk density--0.75 to 0.90 g/cm3
*Glass content--5 to 30 percent
*Ammonium oxalate aluminum plus one-half iron--2 to 3 percent
*15-bar water retention--5 to 12 percent (air-dried samples)
*Rock fragment content--0 to 20 percent
Oi horizon
Thickness--0 to 8 cm
A horizon
Hue--7.5YR, 10YR
Value--3 to 5 dry, 2 or 3 moist
Chroma--2 to 4 dry, 1 to 3 moist
Reaction--slightly acid or moderately acid
Thickness--25 to 56 cm
Bw horizon
Hue--7.5YR, 10YR
Value--4 or 5 dry, 3 or 4 moist
Chroma--2 to 4 dry or moist
Texture--ashy sandy loam, gravelly ashy sandy loam, cobbly ashy sandy loam
Reaction--5.6 to 6.5
Thickness--38 to 56 cm
2Bt horizon
Hue--7.5YR, 10YR
Value--4 or 5 dry, 3 or 4 moist
Chroma--3 to 6 dry, 3 or 4 moist
Texture--very gravelly loam, very cobbly loam, very stony loam, extremely gravelly loam, very gravelly clay loam
Reaction--5.1 to 6.5
Combined thickness--greater than 30 cm
COMPETING SERIES: None
GEOGRAPHIC SETTING:
Elevation--790 to 1475 m
Climate--warm, dry summers; cool, moist winters
Mean annual precipitation--890 to 1300 mm, dominantly snow
Mean annual air temperature--6 to 7 degrees C
Frost-free season--70 to 100 days
GEOGRAPHICALLY ASSOCIATED SOILS:
Kakyawala--on benches and side slopes; no argillic horizon
Nank--on mountain benches, plateaus and side slopes; volcanic ash mantle 36 to 64 cm thick; ashy over loamy particle-size class
Nchitaak--on mountain benches, plateaus, and side slopes; ashy-skeletal over loamy-skeletal particle-size class
Wanaishchit--on plateaus and side slopes; ashy over loamy particle-size class
DRAINAGE AND SATURATED HYDRAULIC CONDUCTIVITY:
Drainage class--well drained
Saturated hydraulic conductivity (Ksat)--moderately high
USE AND VEGETATION:
Use--timber production, livestock grazing, watershed, wildlife habitat, recreation
Native vegetation--grand fir, Douglas-fir, western larch, vine maple, California hazel, creeping snowberry, queencup beadlily, broadleaf starflower, false Solomon's seal, northern twinflower, tall Oregon grape
DISTRIBUTION AND EXTENT: Eastern slopes of Cascade Mountains in Washington, Yakama Nation, Yakima County; MLRA 6; small extent
SOIL SURVEY REGIONAL OFFICE (SSRO) RESPONSIBLE: Portland, Oregon
SERIES ESTABLISHED: Yakama Nation, Yakima County, Washington; 2014
REMARKS:
Diagnostic horizons and other features recognized in this pedon
*Umbric epipedon--zone from 3 to 28 cm
*Cambic horizon--zone from 28 to 86 cm
*Argillic horizon--zone from 86 to 160 cm
*Andic soil properties--zone from 3 to 86 cm
*Particle-size control section--zone from 3 to 103 cm
Values for andic soil properties, including glass content, acid oxalate aluminum and iron, and 15-bar water retention, were estimated based on laboratory data from similar soils.
Yikw'il is the Yakama word for muddy. The type location for this series is in the vicinity of Swamp Creek. In 2004, the series originally was named the Pulu series.
ADDITIONAL DATA:
Partial laboratory data--sample number 56B-16-3; Yakama Nation Soils Laboratory, Toppenish, Washington
National Cooperative Soil Survey
U.S.A.