Mountain pine beetle and northern caribou: the Itcha-Ilgachuz experience

The purpose of the Itcha-Ilgachuz Research Project is to develop and test silvicultural systems that maintain caribou habitat, including terrestrial and arboreal forage lichens, while extracting timber. To develop a viable silvicultural system we are also researching regeneration (planted and natural), breeding birds, microclimate, long-term site productivity, treefall, and growth and yield. We are also addressing the implications of high tree mortality, caused by mountain pine beetle (mpb), to caribou and other values. The current attack on the Chilcotin Plateau is causing much higher stand mortality than that experienced in the 1980s and a larger proportion of the landscape is affected. Irregular group shelterwood and group selection have been tested for over 10 years and results indicate these are viable silvicultural systems. With the arrival of mpb they remain a key part of the management approach. These systems have the potential to maintain habitat because: (1) the stand, even with mostly dead trees, still provides partial shade for lichens for about 20 years; (2) this gives regeneration a chance to grow for 20 years to provide future partial shade for lichens; (3) mobility is not an issue with 50% of the trees harvested; and (4) the standing dead trees provide a source of arboreal lichen fragments for the regenerating openings. Ongoing measurements will determine whether these initial indications are correct.