Soils of the - Agriculture and Agri-Food Canada

SHALISH SOILS
Location and Extent : Shalish soils are common on the floors and lower walls of most mountain valleys in th e
map area . About 2040 ha of pure map units and 5200 ha of soil complexes dominated by Shalish soils ar e
mapped . Most complexes are with Isar soils although lesser areas in complexes with Strachan, Seymour an d
Sardis soils also occur .
Topography and Elevation : The topography of Shalish soils generally varies from strongly to steepl y
sloping with slope gradients between 10 and 30 percent . Elevations range from sea level to about 300 m abov e
sea level .
Parent Material and Texture : Shalish soils have developed from stony and bouldery, coarse-texture d
alluvial fan deposits . Surface textures vary from gravelly sandy loam to gravelly loamy sand, both stony .
Subsurface textures are mainly gravelly loamy sand or gravelly sand and grade to gravelly sand or sandy grave l
in the subsoil . Coarse fragments usually range, by volume, from about 50 percent in the surface to between 6 0
and 90 percent in the subsurface and subsoil .
Soil Moisture Characteristics : Shalish soils are moderately well to well drained . They are rapidly perviou s
for the most part although a few moderately pervious areas also occur where discontinuous cementation exist s
in the lower subsoil . Water holding capacity is low and surface runoff is slow . Telluric seepage through the lowe r
subsoil is common during and after heavy rains or during snowmelt .
General Soil Description : Shalish soils generally have an organic surface litter layer between 5 and 15 c m
thick which is mainly well-decomposed, matted and dark reddish brown to black in colour . It is underlain by a
weakly structured, gray to reddish-gray, strongly leached, sandy and gravelly layer about 4 to 8 cm thick . In turn ,
this is abruptly underlain by a dark reddish brown, organic matter enriched (10 to 15 percent organic matte r
content), friable, weakly structured, sandy and gravelly layer about 15 cm thick that contains about 50 percen t
coarse fragments . This layer grades to about 75 cm of friable, weakly structured, stony and bouldery, gravell y
sand or sandy gravel that is usually dark reddish brown in the upper part and reddish-brown near the botto m
and contains variably coloured mottles in the lower part as well . Under this, usually, is loose, stony and bouldery,
gravelly and sandy material or sometimes, a layer of massive, moderately cemented, similarly textured ,
brownish-gray or reddish-brown material . Where cementation exists a zone of root concentration is usuall y
present on its' surface and variable amounts of telluric seepage is present in this zone also . Soil reaction grade s
from extremely acid in the upper soil to very strongly or strongly acid in the lower subsoil . Soil classification i s
mainly Orthic Ferro-Humic Podzol although some areas of Duric Ferro-Humic Podzols are also included where
the subsoil cementation is stronger than usual and is relatively continuous .
Commonly Associated Soils : Isar soils are usually associated with Shalish soils ; sometimes Seymour an d
Sardis soils are closely associated as well . Isar soils are texturally similar to Shalish soils but have little soil profil e
development (are regosolic) . They are usually found on the actively depositing or recently deposited portions o f
the alluvial fans while the Shalish soils occupy the older, more stable fan areas . Seymour and Sardis soils differ
from Shalish soils by being imperfectly drained and usually lie at lower topographic positions than do Shalis h
soils . The alluvial fans deposits which form the parent material of Shalish soils frequently overlie the fluvial
terraces on which Seymour and Sardis soils occur .
Vegetation : The natural vegetation on Shalish soils usually consists of coast Douglas-fir, western hemloc k
and western red cedar ; red alder, maple and some black cottonwood are prevalent in second-growth areas .
Rooting, except for limitations imposed by the high coarse fragment content, is unrestricted to at least 100 cm .
Below this depth, restriction sometimes occurs because of discontinuous cementation .
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