The key is diversity. On the other hand, clearcuts simplify both the type of structure and its pattern on the landscape. There is no diverse mosaic. However, simplifying ecosystem patterns has untold consequences for biodiversity because species are adapted to this natural diversity in forest structure. A bird that nests in large, soft snags has no where to go if those snags disappear from the landscape.
Many species are invertebrates or soil organisms, both poorly known to science.
However, if we can keep all the patterns, the diversity of forest structure across the landscape, we can hopefully keep all the species and their functions. For this reason, forest management policy, such as in BC and Ontario, is now based on the idea that logging needs to mimic natural disturbance patterns in order to maintain at least some of this structural diversity to safeguard biodiversity. To paraphrase Aldo Leopold, intelligent tinkering isn t saving all the parts. It s saving all the patterns. The parts, the species, depend on the patterns.