LOCATION TRONSEN                 WA

Established Series
Rev. JP/VB/RWL
09/2019

TRONSEN SERIES

Landscape--plateaus, hills, canyonlands, mountains
Landform--benches, ridgetops, hillslopes, canyons, mountain slopes
Slope--2 to 65 percent
Parent material--residuum and colluvium derived from basalt or andesite mixed with loess and volcanic ash in upper part
Mean annual precipitation--about 360 mm
Mean annual air temperature--about 8 degrees C
Depth class--very deep
Drainage class--well drained
Soil moisture regime--xeric
Soil temperature regime--mesic
Soil moisture subclass--typic

TAXONOMIC CLASS: Clayey-skeletal, smectitic, mesic Vitrandic Palexerolls

TYPICAL PEDON: Tronsen stony ashy silt loam in an area of rangeland, on a 60-percent, south-facing slope at an elevation of 1150 m (The soil was moist when described. All textures are apparent field textures.)

A--0 to 23 cm; stony ashy silt loam, dark grayish brown (10YR 4/2) dry, very dark grayish brown (10YR 3/2) moist; weak medium granular structure; slightly hard, friable, slightly sticky and slightly plastic; many fine roots; common fine and medium tubular pores; 15 percent gravel, 5 percent cobbles, and 5 percent stones; 1 percent surface stones; neutral (pH 6.8); clear smooth boundary

BAt--23 to 41 cm; very gravelly clay loam, brown (10YR 4/3) dry, dark brown (10YR 3/3) moist; weak fine subangular blocky structure; hard, firm, moderately sticky and moderately plastic; common fine and medium roots; common fine and medium tubular pores; common faint clay films on surface of peds; 30 percent gravel and 10 percent cobbles; neutral (pH 6.8); clear wavy boundary

Bt1--41 to 76 cm; very gravelly clay loam, yellowish brown (10YR 5/4) dry, dark yellowish brown (10YR 4/4) moist; weak medium subangular blocky structure; very hard, very firm, moderately sticky and moderately plastic; common fine and medium roots; common fine tubular pores; common faint clay films on faces of peds; 30 percent gravel and 10 percent cobbles; neutral (pH 6.6); clear wavy boundary

Bt2--76 to 150 cm; extremely gravelly clay, pale brown (10YR 6/3) dry, brown (10YR 4/3) moist; moderate coarse subangular blocky structure; massive; extremely hard, extremely firm, very sticky and very plastic; few fine roots; common fine and medium tubular pores; few faint clay films on faces of peds; 50 percent gravel and 15 percent cobbles; neutral (pH 6.6)

TYPE LOCATION: Chelan County, Washington, about 8 km northwest of Sunnyslope and 120 m east of Eagle Rock; near the center of section 30, T. 24 N., R. 20 E., Willamette Meridian

RANGE IN CHARACTERISTICS:
Mean annual soil temperature--8 to 11 degrees C
Moisture control section--usually moist, but dry 90 to 105 consecutive days following summer solstice
Thickness of mollic epipedon--25 to 50 cm
Particle-size control section--averages 35 to 80 percent rock fragments and 35 to 50 percent clay

Upper 20 to 30 cm
*Moist bulk density--1.2 to 1.5 g/cm3
*Volcanic glass content--10 to 25 percent
*Acid oxalate aluminum plus one-half iron--0.15 to 0.35 percent
*15-bar water retention--5 to 10 percent (air-dried samples)

A horizon
Hue--10YR, 7.5YR
Value--4 or 5 dry, 2 or 3 moist
Chroma--1 to 3 dry or moist
Texture--stony ashy silt loam, stony ashy loam
Thickness--18 to 28 cm

BAt horizon
Hue--10YR, 7.5YR
Value--4 or 5 dry
Chroma--2 or 3 dry or moist
Texture--very gravelly clay loam, very gravelly clay, very cobbly clay loam
Thickness--13 to 23 cm

Bt horizon
Hue--10YR, 7.5YR
Value--4 to 6 dry, 3 to 5 moist
Chroma--3 or 4 dry or moist
Texture--very gravelly clay, very gravelly clay loam, very cobbly clay loam, extremely gravelly clay, extremely gravelly clay loam, very cobbly clay
Reaction--6.6 to 7.8
Combined thickness--greater than 99 cm

COMPETING SERIES:
Palerf--63 to 100 cm (moderately deep) to a lithic contact (basalt)
GEOGRAPHIC SETTING:
Elevation--240 to 1275 m
Climate--warm, dry summers; cool, moist winters
Mean annual precipitation--310 to 410 mm
Mean January air temperature--about -4 degrees C
Mean July air temperature--about 21 degrees C
Mean annual air temperature--about 8 to 10 degrees C
Frost-free season--120 to 165 days

GEOGRAPHICALLY ASSOCIATED SOILS:
Benwy--on old alluvial fans; fine-loamy particle-size class
Cheviot--on hillslopes; loamy-skeletal particle-size class
Yaxon--on hillslopes; fine-loamy particle-size class

DRAINAGE AND SATURATED HYDRAULIC CONDUCTIVITY:
Drainage class--well drained
Saturated hydraulic conductivity (Ksat)--moderately low

USE AND VEGETATION:
Use--livestock grazing, wildlife habitat, watershed, recreation
Native vegetation--bluebunch wheatgrass, Sandberg bluegrass, Wyoming big sagebrush, antelope bitterbrush

DISTRIBUTION AND EXTENT: Central Washington; MLRA 8; moderate extent

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

SERIES ESTABLISHED: Chelan County, Washington; 1969

REMARKS:
Diagnostic horizons and other features recognized in this pedon
*Mollic epipedon--zone from the surface to a depth of 41 cm
*Argillic horizon--zone from 23 to 150 cm; increase in clay of more than 15 percent (absolute) within 3 cm and no decrease in clay by as much as 20 percent within a depth of 150 cm
*Vitrandic feature--zone from the surface to a depth of 23 cm
*Particle-size control section--zone from 23 to 73 cm

---

National Cooperative Soil Survey
U.S.A.