Plantations of genetically improved forest trees are critical for economic sustainability in forestry. This review summarizes gains in objective traits and the resulting economic impact of tree breeding programmes in Scandinavia and Finland. Genetic improvement of forest trees in these countries began in the late 1940s, when the first phenotypically superior plus-trees were selected from natural environments. The main findings from this review are that (i) tree breeding can increase volume growth in the range 10–25%, and (ii) the bare land value associated with genetically improved trees gives a better return on investment and a shorter rotation period compared to the unimproved forests. As some Nordic countries are quite dependent on the forest industry, breeding programmes that have resulted in economic gains have been beneficial for society. Growth and wood quality traits are often adversely correlated, and the weighting of traits from an economic perspective could provide an index for determining maximum profit from breeding. Tree breeding faces an array of challenges in the future, such as changes in silviculture, climate, new pests and diseases, and demand for wood-based products.

Large-scale transfer of reproductive material is a common phenomenon in forestry and is not only limited to recent history. Here we review the historical transfer of forest reproductive material (FRM) in Fennoscandia, the directions, their drivers, and the reported consequences for adaptation and gene pools of key forest tree species. We find that large imports of non-native FRM occurred from the 19th century onwards, partly due to prior deforestations directly associated with charcoal production for mining, extraction of timber and production of tar and pitch which have historically been important export commodities for Sweden, Norway, and Finland. In Denmark, conversion to agricultural land and the use of forests for livestock feeding was similarly important. During the subsequent reforestation efforts in Denmark, the introduction and use of non-autochthonous FRM of beech, oak and Scots pine became prevalent. Norway spruce FRM was extensively introduced to Sweden and Norway, and Scots pine FRM was imported to Sweden. Finland, in contrast, has limited records of FRM introductions. The importation of conifer seed to Norway and Sweden was initially driven by demand for large quantities of seed associated with the practice of direct seeding which prevailed until the mid-20th century. Large-scale changes to land ownership appear to have facilitated the logging of forests and subsequent seed imports for regeneration. Awareness of provenance variation in adaptive traits emerged gradually from the 19th century and led to more targeted imports of FRM to specifically improve climatic adaptation, trait qualities and growth, from the early 20th century. This, in turn, triggered the development of national regulations and guidelines from the 1930s to control the use of FRM, and marked a shift in forest legislation that had historically only been designed to control harvesting. Due to the geographical scales involved, transfers of FRM have unquestionably affected native gene pools, especially for species such as Norway spruce, Scots pine, beech, sessile and pedunculate oak, although relatively few examples of adaptive failures due to transfer have been reported.