Soils of the - Agriculture and Agri-Food Canada

STURGEON SOILS (SG)
Location and Extent : Sturgeon soils occur mainly in the Pitt Polder area and in the northern part of Pit t
Meadows Municipality. Lesser areas are found along the western edge of the lower Pitt River and near the mout h
of Widgeon Creek . About 320 ha of pure map units and 1550 ha of soil complexes dominated by Sturgeon soil s
are mapped . Most complexes are with Addington, Alouette and Widgeon soils .
Topography and Elevation : The topography of Sturgeon soils varies from slightly depressional or nearl y
level to gently undulating with slopes of less than 2 percent . All areas lie less than 5 m above sea level .
Parent Material and Texture : Sturgeon soils have developed from medium-textured, mixed floodplai n
deposits of the Alouette, Pitt and Fraser Rivers, capped by 20 to 40 cm of mostly well-decomposed organi c
material . Surface texture is humic, usually containing from 20 to 50 percent silt . The subsurface is silt loam ,
occasionally varying to silty clay loam or silt . The upper subsoil is similar but below depths of 100 cm or more ,
the texture gradually changes to fine loamy sand or fine sandy loam .
Soil Moisture Characteristics : Sturgeon soils are very poorly to poorly drained . They are moderatel y
pervious and have high water holding capacity and slow surface runoff . The watertable is at or near the surfac e
for most of the winter and recedes only slightly during the summer . Undyked areas are susceptible to flooding .
General Soil Description : Sturgeon soils usually have about 10 cm of black, well-decomposed, friable ,
granular, organic material at the soil surface . This grades to a further 30 cm of very dark brown to dark yellowis h
brown, friable, organic material that contains variable amounts of silt (usually 20 to 50 percent) and crack s
vertically on drying . This is underlain by about 50 cm of silty material that is massive, dark grayish brown i n
colour, friable and contains few to common, dark brown to reddish-brown mottles . Occasional vertical crack s
are present which contain organic material from above . Under this is massive, very dark gray to olive-gray, silty
or fine sandy material that contains common, prominent, brownish mottles along old root channels . Soil reactio n
grades from extremely acid in the upper soil to medium or very strongly acid below 100 cm depth . Soi l
classification is Rego Gleysol:peaty phase.
Commonly Associated Soils : Alouette, Widgeon and Addington soils often are closely associated with
Sturgeon soils . Alouette soils are generally similar to Sturgeon soils except that the upper part of the minera l
subsurface layer is well structured . Alouette soils are also usually slightly better drained than are Sturgeon soils .
Addington soils are usually more poorly drained and have water on the soil surface for large parts of the year .
The mineral subsurface and subsoil of Addington soils is also more sandy than are those in Sturgeon soils .
Widgeon soils differ by being organic in the upper 40 to 160 cm .
Vegetation : Cultivated (and drained) areas are used mostly for forage production and some blueberries . The
majority of Sturgeon soils are undeveloped and support a variety of moisture tolerant species including sedge s
and reeds, willow, some black cottonwood, hardhack, sweet gale and others . Rooting is confined mainly to th e
upper 60 cm by the high groundwater tables .
General Land Use Comments : (1) Where unreclaimed, Sturgeon soils are agriculturally limited to mainl y
permanent pasture uses. With adequate watertable control (both subsurface and flooding), these soils ar e
potentially suited for most crops, except perhaps, those that are especially susceptible to periodic we t
conditions . (2) Urban and related uses are generally unsuited for Sturgeon soils . Bearing strengths are variabl e
(usually low), a flooding hazard is present in most locations and high watertables preclude basements an d
severely inhibit operation of septic tank effluent disposal fields . (3) High watertables and periodic floodin g
preclude most commercial tree species .
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