Ecosystems Unevenly Represented

How well a landscape's ecosystems are represented in non-harvestable forests varies throughout British Columbia.

These forests are deemed non-harvestable by forestry regulations, such as for riparian areas, or are unsuited to logging because of their inaccessibility or poor productivity.

In the regions of BC surveyed, a higher fraction of forested land is considered non-harvestable than is formally designated as protected.

In Clayoquot Sound the 62 percent of forested area set aside as non-harvestable contains good coverage of all biogeoclimatic zone variants. For areas studied elsewhere on Vancouver Island and in the Okanagan, ecological representation is more uneven. Here, non-harvestable forests form 22 to 26 percent of the landscape and they comprise far greater proportions of forests at high elevations than at lower sites. The ecologically richer spots, with high site index stands, are also much less likely to be mapped as non-harvestable.

Another common feature of non-harvestable areas, except at Clayoquot Sound, is their proximity to harvestable stands. Half of the non-harvestable forests examined are located within 50 m of a forest that has been or will be logged. Forest edges can affect the ecology of unharvested areas, unless special efforts are made to manage this.

Closer examination of some forests reveals that non-harvestable stands have fundamental structural differences from forests destined for logging. Mature stands set aside from harvesting in the Engelmann Spruce - Subalpine Fir zone near Arrow Lakes have substantially fewer snags and logs, while live trees grow less vigorously than in commercial forests.