Interaction Between Douglas Fir Regeneration And Frost In Central British Columbia

Regenerating British Columbia's Forests will assist those responsible for planning reforestation projects to reach informed decisions and will challenge them to consider primarily the biological factors basic to reforestation success rather than short-term costs and production technology. Although its main audience is practising foresters and forestry students of British Columbia, the text will be of considerable interest to foresters in other parts of Canada, the United States, and Europe who manage reforestation.

This study was initiated in 2001 as part of a uniform shelterwood trial located in the dry, warm Sub-Boreal Spruce subzone (sbsdw) near Williams Lake, B.C., after a second harvesting entry was completed. The focus of the main trial was to test various levels of residual basal retention and harvesting methods on the establishment, survival, and productivity of Douglas-fir regeneration. The microclimate component was set up to help interpret tree performance by comparing the climate conditions among three of the residual basal area treatments (0, 15, and 20 m2/ha). The objectives for the microclimate portion of the shelterwood project were to compare soil temperatures and snow-free periods among the three residual basal area treatments (0, 15, and 20 m2/ha); to compare the incidence, duration, and severity of growing season frosts among the three residual basal area treatments (0, 15, and 20 m2/ha); and to investigate the effects of local canopy density on minimum near-ground air temperatures and duration of frost events during the growing season.--Document.

Silvicultural practices in the Douglas-fir region evolved through a combination of formal research, observation, and practical experience of forest managers and silviculturists, and changing economic and social factors. This process began more than a century ago and still continues. It has had a great influence on the economic well-being of the region and on the present characteristics of the regions forests. This long history is unknown to most of the public, and much of it is unfamiliar to many natural resource specialists outside (and even within) the field of silviculture. We trace the history of how we got where we are today and the contribution of silvicultural research to the evolution of forest practices. We give special attention to the large body of information developed in the first half of the past century that is becoming increasingly unfamiliar to both operational foresters andperhaps more importantlyto those engaged in forestry research. We also discuss some current trends in silviculture and silviculture-related research.