Old forest remnants contribute to sustaining biodiversity: The case of the Albert River valley

The Albert River valley hosts the only old-growth stands of western redcedar in the Invermere Timber Supply Area (TSA). This portion of the Interior Cedar Hemlock moist cool (ICHmk1) biogeoclimatic variant is spatially disjunct from the rest of the ICHmk1 in British Columbia and lies on calcareous soil. Surveys of lichens and vascular plants in the valley bottom of the Albert River revealed an uncommonly rich area, including about 10% of the vascular plant species known to British Columbia. Eight of these are either Blue- or Red-listed in the province. Nine of the lichens found are either new to North America, western North America, or British Columbia, and seven may be new to science. Four more species have a predominantly oceanic distribution, and one is mainly Arctic. Conserving remnants of old-growth forest from forest harvest can play a critical role in sustaining biodiversity, particularly those in rare and poorly represented ecosystem types, so these areas merit careful consideration in the designation of reserves. Such significant remnants are easily overlooked when assessment of potential conservation areas is restricted to coarse-scale approaches that focus on intact landscapes. Coarse-filter approaches can identify potential rare ecosystems and guide field surveys, but are no substitute for field surveys.