Hello, Ekaitz. The three trees clear up in winter, they lose their foliage. Both oak (Quercus robur), beech (Fagus sylvatica), and birch (Betula pubescens) are the times when it is changed: the winter moon, this year between 24 January and 4 February. The winter stop is used for planting work. Do it as quickly as possible, as long as there is no fear of ice. If it is very cold, crush the soil well on the roots after planting and put a lot of new manure on top of it to prevent the cold from getting through the slits of the soil. Without forgetting it: planting the land at the same level as before in the neck of the tree once planted.
When choosing the usual place of residence for trees, it should be borne in mind that most of the water is required by birch, the beech will also be grateful for water, while the oak will be adapted in a drier terrain.