Koksilah Ridge (''Hwsalu'utsum'') is an elevated area located south of the

Cowichan Valley The Cowichan Valley is a region around the Cowichan River, Cowichan Bay and Cowichan Lake on Vancouver Island, in British Columbia, Canada. There is some debate as to the origin of the name Cowichan, which many believe to be an anglicized form ...

on Vancouver Island, British Columbia. It is centered at 48°42′N, 123°47′W. Its summit lies about above sea level. It is visible in most of the Cowichan Valley and on the

Saanich Peninsula Saanich Peninsula ( str, W̱SÁNEĆ) is located north of Victoria, British Columbia, Canada. It is bounded by Saanich Inlet on the west, Satellite Channel on the north, the small Colburne Passage on the northeast, and Haro Strait on the east. The ...

north of

Brentwood Bay Brentwood Bay is a small village in the municipality of Central Saanich, on the Saanich Peninsula in British Columbia, Canada. It lies north of the city of Victoria, east of the community of Willis Point, and south of the town of Sidney. Situate ...

. As seen from

North Saanich The District of North Saanich is located on the Saanich Peninsula of British Columbia, approximately north of Victoria, British Columbia, Victoria on southern Vancouver Island. It is one of the 13 Greater Victoria municipalities. The District ...

Sidney Sidney may refer to: People * Sidney (surname), English surname * Sidney (given name), including a list of people with the given name * Sidney (footballer, born 1972), full name Sidney da Silva Souza, Brazilian football defensive midfielder * ...

, it is plough-shaped, with long gentle slopes. From north to south, the bedrock

lithology The lithology of a rock unit is a description of its physical characteristics visible at outcrop, in hand or core samples, or with low magnification microscopy. Physical characteristics include colour, texture, grain size, and composition. Lit ...

begins with Cretaceous-era sedimentary rock, chiefly

shale Shale is a fine-grained, clastic sedimentary rock formed from mud that is a mix of flakes of clay minerals (hydrous aluminium phyllosilicates, e.g. kaolin, Al2 Si2 O5( OH)4) and tiny fragments (silt-sized particles) of other minerals, especial ...

, sandstone and

conglomerate Conglomerate or conglomeration may refer to: * Conglomerate (company) * Conglomerate (geology) * Conglomerate (mathematics) In popular culture: * The Conglomerate (American group), a production crew and musical group founded by Busta Rhymes ** Co ...

. These sediments extend up to about . Above them lies a

pluton In geology, an igneous intrusion (or intrusive body or simply intrusion) is a body of intrusive igneous rock that forms by crystallization of magma slowly cooling below the surface of the Earth. Intrusions have a wide variety of forms and com ...

of Jurassic-age granodiorite, which underlies the summit. Around the eastern, southern and western edges of this pluton is a complex association of

Pennsylvanian Pennsylvanian may refer to: * A person or thing from Pennsylvania * Pennsylvanian (geology) The Pennsylvanian ( , also known as Upper Carboniferous or Late Carboniferous) is, in the International Commission on Stratigraphy, ICS geologic timesca ...

-era argillite, greywacke, chert and

diabase Diabase (), also called dolerite () or microgabbro, is a mafic, holocrystalline, subvolcanic rock equivalent to volcanic basalt or plutonic gabbro. Diabase dikes and sills are typically shallow intrusive bodies and often exhibit fine-graine ...

. The soils of Koksilah Ridge are well or rapidly drained gravelly sandy loams and gravelly loamy sands with podzol profile development. They support Coastal Western Hemlock-type forests in which Douglas-fir and western hemlock are most common at lower elevations. These forests are classified under the provincial Biogeoclimactic Ecosystem Classification as Coastal Western Hemlock, Very Dry Maritime Subzone (CWHxm2). Areas above are mapped as Coastal Western Hemlock, Moist Maritime Subzone (CWHmm2), with abundant Douglas-fir,

amabilis fir ''Abies amabilis'', commonly known as the Pacific silver fir, is a fir native to the Pacific Northwest of North America, occurring in the Pacific Coast Ranges and the Cascade Range. It is also commonly referred to as the white fir, red fir, love ...

, and western hemlock. The forest industry has been active on Koksilah Ridge for many years and the native forest is interrupted by logged-off areas of varying size. These clear cuts are prominent when a snow cover is present. Snow may lie on the higher parts for up to six months over a severe winter, but is seen on only a few days through a mild winter. Island Timberlands presently has tenure.

References

Further reading