Overview Ilgachuz Range To preserve extensive and diverse alpine-subalpine ecosystems in an isolated massif of volcanic origin

Posted April 16, 1980 | Categories : 64,Reports,Species List |

Original Purpose: To preserve extensive and diverse alpine-subalpine ecosystems in an
isolated massif of volcanic origin

Physical: The Ilgachuz Range is one of three distinct mountain masses which lie within the confines of the Fraser Plateau in the Anahim Lake area. All were formed by shield volcanoes of Miocene age which built up dome-like piles of lava and fragmented rock. Volcanic peaks, rugged scarps and extensive talus slopes characterize the southwestern half of the reserve, while gently sloping lava flows underlie much of its northeastern area. Although these mountains have been dissected by stream erosion and molded by glaciers, their original shape has been largely preserved. Alpine features such as patterned ground, boulder stripes and solifluction lobes are present.


See the complete version in PDF ilgachuz

Biological:About two-thirds of the reserve is in the alpine zone, which consists of both vegetated areas and bare rock. Forested land, dominated by Subalpine fir, is largely restricted to the lower valley slopes. A great variety of herbaceous communities is present in this topographically diverse area. Well-drained alluvial sites at low elevation support Altai fescue-mountain-avens or willow-fescue associations. In wet areas along Blue Canyon Creek one finds cotton-grass-sedge bog, sedge-bluejoint meadow and scrub birch-sedge shrubland. Seepage slopes and wet meadows near timberline have lush wildflower communities dominated by arrowleaved groundsel and containing red paintbrush, Indian hellebore, subalpine daisy and Sitka valerian. Black alpine sedge stands occur in late snowmelt sites. At timberline a community dominated by Altai fescue and mountain sage occurs on fairly level, dry sites, while white and pink mountain- heather occupy slopes between patches of stunted subalpine fir. The most extensive alpine community, common on the rather arid gentle northeast slope of Tundra Mountain, is dominated by Altai fescue, white mountain-avens, netted willow and lichens.
The fauna has not been surveyed, but the Ilgachuz Range has high capability habitat for caribou, moose and mountain goats.

RESEARCH OPPORTUNITIES: The reserve is an area of biogeographic interest since many plants and some animals reach their northernmost or southernmost limits here. This would be a good area to characterize now with a baseline survey and repeat at intervals to record the impacts of climate change.


birch, scrub (Betula nana)
cotton-grass, narrow leaved, (Eriophorum angustifolium)
daisy, subalpine (Erigeron peregrinus)
draba, milky (Draba lacteal)
draba, Payson’s (Draba paysonii)
fescue, Altai (Festuca altaica)
fir, subalpine (Abies lasiocarpa var. lasiocarpa)
groundsel, arrow-leaved (Senecio triangularis)
hellebore, Indian (Veratrum viride)
koenigia, Iceland (Koenigia islandica)
mountain-avens, white (Dryas octopetala)
mountain-heather, pink (Phyllodoce empetriformis)
ountain-heather, white (Cassiope mertensiana var. mertensiana)
paintbrush, scarlet (Castilleja miniata)
reedgrass, bluejoint (Calamagrostis canadensis)
sagewort, mountain (Artemisia norvegica ssp. saxatilis)
sedge, black alpine (Carex nigricans)
valerian, Sitka (Valeriana sitchensis)
willow, net-veined (Salix reticulata)


FAUNA:Caribou (boreal population) (Rangifer tarandus pop. 14)
Goat, Mountain (Oreamnos americanus)
Moose (Alces americanus)