What species of tree was sacred to the Norse god Thor?

The oak is a deciduous tree, which means it loses its leaves in the autumn and regrows them in the spring. It has soft leaves that break down easily once they’ve fallen to the ground and this and the mould it creates can form the perfect environment for many insects.

The Romans and Greeks associated the oak with their gods, and Norse mythology claimed the tree was sacred to Thor, the thunder god, not surprising as the oak has a reputation for being the most lightning struck tree in the forest (mainly because it’s often the tallest tree in the forest), and for not only surviving this, but thriving afterwards.

In Germanic mythology, Thor is a hammer-wielding god associated with lightning, thunder, storms, sacred groves and trees, strength, the protection of mankind, hallowing, and fertility.

Thor is a prominently mentioned god throughout the recorded history of the Germanic peoples, from the Roman occupation of regions of Germania, to the Germanic expansions of the Migration Period, to his high popularity during the Viking Age, when, in the face of the process of the Christianization of Scandinavia, emblems of his hammer, Mjölnir, were worn and Norse pagan personal names containing the name of the god bear witness to his popularity.