The Yggdrasil tree is at the center of Ragnarok and the poetic edda paints such an image of its destruction but we are getting ahead of ourselves.
The depiction of the 9 realms which the roots of the tree are found shows such a diverse environment and creatures inhabiting it.
There will be destruction when hosts of Muspelheim ride over Bifrost, but the fate of Yiggdrasil remains unknown :)