ABSTRACT
Trees are planted for many reasons and have a wide range of uses, including production of timber, pulpwood, environmental protection, recreation, urban forests, and nature recreation. Many factors influence the success of such plantings, but in this chapter only one factor of major importance will be considered: the importance of selecting the right genetic material. Selection of appropriate genetic material is an important decision, as it will influence all phases of a plantation from establishment to harvest. If trees are allowed to regenerate naturally, or if stands are subsequently used for seed collection, the selection of planting material will also influence the success and quality of future forests.
Appropriate genetic material can increase the amount and quality of the products deriving from the plantations, economic output, resistance to pests and diseases, and stability of the trees. Using inappropriate genetic material, on the other hand, may lead to suboptimal timber outputs or poor stability and resistance to windthrow. Some examples will illustrate the importance of selecting the right genetic material, the benefits that can be derived, and the problems that may arise from using suboptimal genetic material. The North American lodgepole pine (Pinus contorta Dougl.) has been planted as an exotic species in Denmark on wind-exposed, infertile coastal sites. Initially, provenances from western coastal areas of the U.S. were assumed to fit Danish maritime conditions. Seed from these origins, however, caused many total stand failures. However, plantings of material from seed of other, more continental sources grow very well in Denmark (Larsen 1997; Wellendorf and Feilberg 1984; Larsen and Nielsen 1982). The success or failure of planting Pinus contorta in Denmark is therefore a question of carefully selecting planting material of optimal origin.
