Role of tree improvement in intensive forest management

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The historical beginnings of forest genetics and the rapid rise of tree improvement as a world-wide movement are briefly sketched. The technological nature, scientific bases and technical methods of tree improvement are broadly reviewed, with major emphasis on boreal and temperate conifers which, historically, have been the main focus of research and practice. Tree improvement is rationalized within the broader forestry milieu, including: supply and demand for forest resources; goals and policies of forest management; concepts and systems of forest production; and potentials and constraints of intensive management. The need to increase forest productivity to meet rising world-wide demands for forest products is driving forestry toward major technological change. Foresters and land managers are embracing concepts of intensive management and applied genetics that profoundly challenge traditional forestry principles and conventional practices. Tree improvement technology is a versatile tool that can be used in various management settings, but it is particularly appropriate and potent when applied within the context of intensive forestry. Impressive results can be expected from the integration of advanced breeding and intensive silvicultural technologies. Modern agricultural crop production exemplifies gains that can accrue from such management intensification. But the agricultural yield strategy — based on cultural enhancement of growing sites and genetic tailoring of crops to improved cultural conditions — poses real and imagined problems for forestry. Aggressive breeding for responsiveness to enhanced cultural conditions will eventually lead to development of trees that are essentially domesticated. The forest manager and tree breeder must carefully consider the possibility of domestication, as a planned or unplanned result of current breeding strategies. The strategy of replacing natural forests on a vast scale with plantations of improved trees — basically a matter of economics — has far-ranging forest policy implications that cannot be ignored in the quest for greater forest productivity. We must strive to increase wood production without jeopardizing the long-term future of the basic forest resource or impairing its ability to supply the other needs of society. By intensifying management on the most productive forest lands, wood production might be concentrated on a smaller land base, thus permitting the much larger remaining areas to be managed more flexibly toward other objectives. Tree improvement provides the means for greatly increasing the benefits flowing from intensive management programs. The tree breeder can mold the genetic potential of production populations to nake the most of silvicultural investments by increasing the quantity and quality of wood produced.