Soils of the - Agriculture and Agri-Food Canada

FELLOWS SOILS .
(FS)
Location and Extent : Fellows soils occur only near the southern end of Coquitlam Lake and in the Statl u
Creek-Chehalis River valleys . There are about 330 ha of pure map units and 1920 ha of soil complexe s
dominated by Fellows soils . The complexes are with Coquitlam and Roach soils .
Topography and Elevation : The topography of Fellows soils is mostly moderately rolling to hilly with slop e
gradients between 10 and 50 percent, but along gullies or on escarpments, the gradients increase to over 6 0
percent . Elevations range between 150 and 300 m above sea level .
Parent Material and Texture : Fellows soils have developed from moderately coarse to coarse-texture d
glaciolacustrine deposits . There usually is 10 to 20 cm of dominantly well-decomposed organic forest litter o n
the soil surface . The texture of the surface mineral soil and upper part of the subsurface is sandy loam, o r
sometimes, fine sandy loam ; the lower subsurface and subsoil are loamy sand or fine to medium sand . The
subsoil is usually varved .
Soil Moisture Characteristics : Fellows soils are moderately well to well drained and moderately pervious .
Downward water movement is impeded in some areas by weak to moderate, discontinuous cementation a t
depths below 70 cm . A temporary, perched watertable develops in the zone of cementation during heavy ,
prolonged rain and lateral, telluric seepage occurs . Water holding capacity is moderate and surface runoff i s
usually slow, except in areas of steeper slopes where it increases to moderate .
General Soil Description : Fellows soils generally have between 10 and 20 cm of organic forest litter on th e
mineral soil surface, most of which is black, matted and well-decomposed (humic) . This is underlain by a
strongly leached, sandy layer that is gray or reddish-gray, weakly structured and from 1 to 5 cm thick . Abruptl y
under this is a 10 to 20 cm thick, dark reddish brown zone of weakly structured, friable, sandy materia l
containing between 10 and 25 percent organic matter and variable amounts of spherical, hard concretions .
This organic matter enriched zone grades to about 40 cm of friable, weakly to moderately structured, sand y
material which is dark yellowish brown to reddish-brown in colour (colour variation is due to uneven organi c
matter distribution) . It, in turn, grades to about 50 cm of firm, olive-gray to dark gray, sandy material which i s
discontinuously weakly to moderately cemented, massive (breaks horizontally along varves when disturbed )
and contains common, prominent, brown to dark yellowish brown mottles . Below about 100 cm depth, loose ,
massive, dark gray, unweathered sand occurs . Soil reaction grades from extremely acid in the organic surfac e
and upper mineral soil to strongly or medium acid in the lower subsoil . Soil classification is usually Orthic Ferro-
Humic Podzol . A few areas of Duric Ferro-Humic Podzol are also included where the subsoil cementation i s
relatively continuous .
Commonly Associated Soils : Coquitlam and Roach soils commonly occur in association with Fellow s
soils . Coquitlam soils are similar to Fellows soils except that they are silty rather than sandy in texture and do no t
have subsoil cementation . Roach soils differ by being gravelly and stony as well as having strongly cemente d
subsurface layers .
Vegetation : The vegetation on Fellows soils consists mainly of second-growth coast Douglas-fir, wester n
hemlock and western red cedar, together with red alder, birch and some vine and bigleaf maple . Rooting i s
unrestricted to depths of 70 cm or so but is impeded below this in some areas by discontinuous cementation .
General Land Use Comments : (1) None of the Fellows soil areas are presently cleared or cultivated .
Where topography is suitable, they have potential for most agricultural crops if supplemental irrigation i s
available . Adequate liming and fertilization is also required . (2) Relatively level areas are suitable for urban an d
similar uses . Care is required to prevent erospn of the sandy deposits . (3) Forest growth is good ; estimate d
mean annual increments for Douglas-fir are 9to 12 m 3/ha/yr. Soil moisture deficiencies during the latter parts o f
dry summers are somewhat limiting .
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