Soils of the - Agriculture and Agri-Food Canada

VEDDER SOILS (VD)
Location and Extent : Vedder soils only occur in the Sumas Valley where about 770 ha of pure map units of
Vedder soils, 120 ha of a shallow variant of Vedder soils and 190 ha of soil complexes dominated by Vedde r
soils are mapped . The complexes are generally with Vye, Buckerfield and Bates soils .
Topography and Elevation : Vedder soils are nearly level to gently undulating and have slopes less than 2
percent . The soils usually occupy depressional landscape positions in relation to adjacent soils . Elevations li e
between 3 and 8 m above sea level .
Parent Material and Texture : Vedder soils have developed from moderately fine to medium-texture d
lacustrine and mixed lacustrine and alluvial deposits, usually 75 cm or more thick, over sand . Surface texture s
are silt loam or silty clay loam . Subsurface textures are mainly silty clay loam, sometimes varying to silty clay ,
while the subsoil is similar until the underlying medium to fine sand is encountered .
Soil Moisture Characteristics : Vedder soils are poorly drained . They are moderately to slowly perviou s
and have high water holding capacity and slow surface runoff. Groundwater tables are near the surface for mos t
of the rainy winter months, then gradually subside over the growing season . Surface ponding sometime s
occurs due to slow permeability and runoff accumulation from adjacent, higher areas .
General Soil Description : Vedder soils have a silty, cultivated surface about 20 cm thick which is friable t o
firm, moderately structured and grayish-brown to dark grayish brown in colour . The surface is underlain b y
about 20 cm of firm, silty to clayey material that cracks vertically on drying, contains common to many, reddish t o
yellowish mottles and has a few clay flows on ped surfaces . This grades to massive, gray to olive-gray, silty to
clayey material at least 40 cm thick, then is either abruptly underlain or grades to sand at depth . Soil reactio n
ranges from medium or strongly acid in the surface to slightly acid in the subsoil (1 :1 H2 O) . Soil classification i s
Orthic Gleysol .
Commonly Associated Soils : Vye, Buckerfield, Annis and Bates soils usually occur in close associatio n
with Vedder soils . Buckerfield soils differ from Vedder soils by having black rather than grayish surfaces . Anni s
soils differ by having organic surfaces between 15 and 40 cm thick . Vye and Bates soils usually occupy slightl y
higher landscape positions than Vedder soils and are imperfectly drained ; Vye soils also differ by having a well -
defined clay accumulation layer in the subsurface . Areas mapped as a shallow variant of Vedder soils ar e
similar to Vedder soils except that the underlying sand occurs at 20 to 50 cm from the soil surface rather than a t
depths greater than 50 cm .
Vegetation : All areas of Vedder soils are cleared and cultivated for agricultural purposes . Most perennia l
crops are grass-clover mixes for pasture and forage ; annual crops include those that are not readily susceptibl e
to periodic high watertables . Rooting is restriçted mainly to the upper 50 cm by the high groundwater tables an d
dense subsoil .
General Land Use Comments : (I) Vedder soils are limited for agricultural uses by high groundwate r
tables during the winter and spring months which damage perennial crops and retard early spring crop growt h
and cultivation . With artificial drainage most crops suited to the Fraser Valley can be produced . (2) Urban and
similar uses are poorly suited for Vedder soils . High watertables make basements and other excavation s
impractical, septic tank effluent disposal is severely restricted and because of variable (usually low) bearin g
strengths, special foundation considerations may be required . Periodic surface flooding is also a hazard . (3 )
Vedder soils appear to be moderately suited for tree species such as black cottonwood . Estimated potential
annual wood production by this species is 9 to 12 m 3/ha/yr.
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