Forest breeding is still in its early stages – in fact, it was only in the 1950s that the entire Northern European region began to focus on it, starting with the selection of plus trees. Specifically, people would walk through the forest looking for trees that they personally liked, based on quality characteristics, as well as diameter and height at a given age.

Collecting seeds from such mature trees would be very difficult, and, furthermore, only a small volume of seeds can be collected from each individual tree. Therefore, scions were collected from them and used for propagation (by grafting them onto a larger number of rootstocks) and for establishing seed orchards.