Soils of the - Agriculture and Agri-Food Canada

SPETIFORE SOILS (SF)
Location and Extent : Spetifore soils occur only on the Fraser River delta, almost exclusively in the centra l
and southern parts of Delta Municipality. About 330 ha of pure map units and 480 ha of soil complexe s
dominated by Spetifore soils are mapped . The complexes are usually with Delta, Vinod and Goudy soils .
Topography and Elevation : Spetifore soils are nearly level to gently undulating with slopes less than 2
percent . They are usually slightly depressional in relation to adjacent soils and lie at elevations less than 3 m
above sea level .
Parent Material and Texture : Spetifore soils have developed from medium-textured deltaic deposits whic h
are deeper than 1 m and usually overlie medium or fine sand . The surface texture is silt loam . Subsurface an d
subsoil textures are usually similar, changing to silty clay loam in a few areas . The subsurface and subsoil, an d
often the surface, are moderately to strongly saline and contain substantial amounts of compounds high i n
sulphur.
Soil Moisture Characteristics : Spetifore soils are poorly to very poorly drained . They are moderatel y
pervious and have high water holding capacity and slow surface runoff . The watertables are usually near or a t
the soil surface during the winter but gradually recede to 50 cm or more during the summer . The underlying
sands are generally permanently saturated with saline water . Temporary surface ponding during heavy ,
prolonged rain is common .
General Soil Description : Spetifore soils generally have a cultivated, silty surface that is about 20 cm thick ,
very dark brown to very dark grayish brown in colour, friable and moderately structured . It contains between 1 5
to 25 percent organic matter and is often weakly or moderately saline . Abruptly underlying the surface is abou t
20 cm of dark gray or dark grayish brown, massive, firm, silty material containing some vertical cracks wit h
reddish to brownish organic coatings on their walls . A few to common, reddish-brown to light yellowish brow n
mottles are also present and the layer is usually moderately to weakly saline . Under this is 50 cm or more of firm ,
massive, dark gray to olive-gray, silty material containing widely spaced vertical cracks . Common to few,
yellowish mottles are present in the upper part which change to reddish-brown in the lower part and hard, ver y
dark gray to dark reddish brown tubules around old root channels are also present . This zone is generall y
moderately to strongly saline and grades below 100 cm to either saturated, strongly saline sand or alternatin g
bands of silt and sand . Substantial amounts of compounds high in sulphur are generally present in the soi l
downwards from the surface layer. Soil reaction is extremely acid to at least 100 cm depth . Soil classification i s
Rego Humic Gleysol:saline phase .
Commonly Associated Soils : Delta, Vinod, Goudy and Guichon soils often occur in close association wit h
Spetifore soils . In common with Spetifore soils, all are saline . In Delta soils, however, the saline conditions do no t
generally occur until depths of 80 cm of more . Vinod soils differ from Spetifore soils by being clayey in th e
subsoil and also by having an organic surface from 15 to 40 cm thick . Goudy soils differ by consisting of organi c
matter from 40 to 160 cm thick while in Guichon soils, sand is encountered between 20 and 50 cm of th e
surface .
Vegetation : Essentially all areas of Spetifore soils are cleared and cultivated . Rooting is mainly restricted t o
the upper 50 to 60 cm by high groundwater levels, saline conditions and massive subsoil .
General Land Use Comments : (1) Spetifore soils are agriculturally limited by high watertables whic h
particularly inhibit overwintering of perennial crops, and by saline soil conditions . Artificial drainage is required
to control watertables and also to help wash out the salts from the soil . (2) Urban and similar uses are poorl y
suited for Spetifore soils . Variable (usually low) bearing strengths probably require special foundations ,
basements and other excavations will contain water at least during parts of the year, and septic tank disposa l
fields are severely impeded by the high watertables . Unless adequately protected, buried utility and othe r
installations are likely to suffer severe corrosion . Periodic surface ponding is also a hazard .
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