LOCATION VERBOORT OR
Established Series
Rev. GEO/JGM/EED
12/2017
VERBOORT SERIES
Landscape--Willamette Valley
Landform--terraces
Slope--0 to 3 percent
Parent material-- alluvium over glaciolacustrine deposits
Mean annual precipitation--about 1150 mm
Mean annual air temperature--about 11 degrees C
Depth class--very deep
Drainage class--poorly drained
Soil moisture regime--aquic
Soil temperature regime--mesic
Soil moisture subclass--xeric
TAXONOMIC CLASS: Fine, mixed, superactive, mesic Xerertic Argialbolls
TYPICAL PEDON: Verboort silty clay loam, cultivated
Ap--0 to 20 cm; silty clay loam, grayish brown (10YR 5/2) dry, very dark brown (10YR 2/2) moist; strong fine subangular blocky structure; hard, friable, moderately sticky and moderately plastic; many very fine roots; many very fine pores; moderately acid (pH 5.8); abrupt smooth boundary
A--20 to 30 cm; silty clay loam, grayish brown (10YR 5/2) dry, very dark brown (10YR 2/2) moist; moderate fine subangular blocky structure; hard, firm, moderately sticky and moderately plastic; many very fine roots; common very fine pores; moderately acid (pH 5.8); clear smooth boundary
E--30 to 48 cm; silty clay loam, gray (10YR 6/1) dry, very dark gray (10YR 3/1) moist; moderate fine subangular blocky structure; hard, firm, moderately sticky and moderately plastic; common very fine roots; common very fine pores; 30 percent fine distinct irregular dark reddish brown (5YR 3/2) masses of oxidized iron on faces of peds; moderately acid (pH 6.0); abrupt smooth boundary
2Btg--48 to 71 cm; clay, grayish brown (2.5Y 5/2) dry, very dark gray (N 3/0), moist; weak medium prismatic structure parting to weak medium subangular blocky; very hard, very firm, very sticky and very plastic; common fine roots in cracks and few fine roots throughout; few very fine tubular pores; pressure faces on vertical faces of peds and 70 percent faint clay films on vertical faces of peds and on surfaces along pores; slightly acid (pH 6.4); abrupt smooth boundary
2BCtg--71 to 84 cm; silty clay, light brownish gray (2.5Y 6/2) dry, dark grayish brown (2.5Y 4/2) moist; weak fine prismatic structure parting to weak fine subangular blocky; very hard, very firm, moderately sticky and very plastic; few very fine roots in cracks; common very fine tubular pores; 70 percent faint very dark gray (N 3/0) clay films on vertical faces of peds; neutral (pH 6.6); gradual smooth boundary
2Cg--84 to 150 cm; silty clay loam, light gray (2.5Y 7/2) dry, dark grayish brown (2.5Y 4/2) moist; massive; hard, firm, moderately sticky and moderately plastic; few very fine roots; few fine and medium pores; 5 percent very dark gray (N 3/0) clay films on surfaces along pores; 25 percent medium distinct irregular brown (7.5YR 4/2) masses of oxidized iron throughout; neutral (pH 6.6)
TYPE LOCATION: Washington County, Oregon, about 0.4 km south of the community of Helvetia; 6 m west of the intersection of Helvetia Road and Phillips Road; about 825 m west and 610 m south of the northeast corner of section 10, T. 1 N., R. 2 W.; latitude 45.5866389, longitude -122.9193611, datum NAD 83 (coordinates estimated from PLSS details)
RANGE IN CHARACTERISTICS:
Mean annual soil temperature--11 to 13 degrees C
Moisture control section--dry in all parts 45 consecutive days or more following summer solstice
Thickness of the mollic epipedon--25 to 43 cm
Depth to aquic conditions--at the surface to a depth of 25 cm
Depth to lithologic discontinuity--41 to 66 cm
Estimated coefficient of linear extensibility (COLE) from the surface to a depth of 100 cm--greater than 6.0
Particle-size control section
*Clay content--35 to 55 percent
*Total fragment content--0 percent
A horizon
Hue--10YR, 2.5Y
Value--2 or 3 moist, 4 or 5 dry
Chroma--1 or 2 moist or dry
Clay content--27 to 35 percent
Sand content--5 to 15 percent
Reaction--5.1 to 6
Thickness--25 to 43 cm
E horizon
Hue--10YR, neutral
Value--3 or 4 moist, 5 to 7 dry
Chroma--1 or less
Fine-earth texture--silt loam, silty clay loam
Clay content--25 to 35 percent
Sand content--5 to 15 percent
Reaction--5.1 to 6
Thickness--15 to 23 cm
2Bt horizon
Hue--2.5Y, 5Y, neutral
Value--3 or 4 moist, 5 or 6 dry
Chroma--2 or less
Fine-earth texture--clay, silty clay
Clay content--40 to 55 percent
Sand content--2 to 10 percent
Reaction--5.6 to 7.3
Thickness--15 to 76 cm
2BCt horizon
Hue--2.5Y, 5Y
Value--4 or 5 moist, 6 or 7 dry
Chroma--2 or 3 moist or dry
Fine-earth texture--clay, silty clay, silty clay loam
Clay content--35 to 50 percent
Sand content--2 to 10 percent
Reaction--5.6 to 7.3
Thickness--0 to 38 cm
2C horizon
Hue--2.5Y, 5Y
Value--4 or 5 moist, 6 or 7 dry
Chroma--2 or 3 moist or dry
Fine earth texture--silt loam, silty clay loam
Clay content--25 to 35 percent
Sand content--5 to 25 percent
Reaction--6.1 to 7.3
COMPETING SERIES: None
GEOGRAPHIC SETTING:
Elevation--45 to 100 m
Climate--warm, dry summers; cool, moist winters
Mean annual precipitation--1000 to 1300 mm
Mean annual air temperature--10 to 12 degrees C
Mean January air temperature--4 degree C
Mean July air temperature--19 degrees C
Frost-free period--165 to 210 days
GEOGRAPHICALLY ASSOCIATED SOILS:
Aloha--aquic conditions at a depth of 25 to 50 cm, fine-silty; in similar positions
Dayton--ochric epipedon; in depressions of higher terraces
Huberly--fragipan; less than 35 percent clay in particle-size control section; in depressions of terraces
Quatama--less than 35 percent clay in particle-size control section; aquic conditions at a depth of 40 to 75 cm; on risers and in convex positions
Willamette--less than 35 percent clay in particle-size control section; on higher terraces
Woodburn--less than 35 percent clay in particle-size control section; on higher terraces
DRAINAGE AND SATURATED HYDRAULIC CONDUCTIVITY:
Drainage class--poorly drained
Saturation in normal years--apparent high water table at the surface to a depth of 25 cm below the surface in November through April
Flooding--frequent, brief periods in December through April
Ponding--none
Saturated hydraulic conductivity (Ksat)--low
USE AND VEGETATION:
Use--production of spring grain, hay, pasture, and vegetable crops
Potential natural vegetation--Oregon ash, willow, sedges, grass
DISTRIBUTION AND EXTENT: Willamette Valley, Oregon; MLRA 2; small extent
SOIL SURVEY REGIONAL OFFICE (SSRO) RESPONSIBLE: Portland, Oregon
SERIES ESTABLISHED: Washington County, Oregon; 1975
REMARKS:
Diagnostic horizons and other features in this pedon
*Particle-size control section--zone from 48 to 84 cm
*Mollic epipedon--zone from the surface to a depth of 30 cm
*Albic horizon--zone from 30 to 48 cm
*Argillic horizon--zone from 48 to 84 cm
*Aquic conditions--zone from 30 to 150 cm
08/2017--This official series description was updated according to SSR01 Technical Note 11--Content and Format of Official Series Descriptions (revised 12/2015). Most of the changes were in formatting; no major technical changes were made.
02/2000--Classification revised from Typic Argialbolls to Xerertic Argialbolls based on the estimate of COLE and addition of Vertic subgroup to Soil Taxonomy.
National Cooperative Soil Survey
U.S.A.