"While some would say this came from the world tree itself, others have their doubts.  Either way, both sides agree; this branch exudes magical energy and grants it's wielder special powers, mimicking Yggdrasil's greatness."

Power of Nature:  The branch can be used as a spellcasting focus thanks to its magical nature.

Life Essence:  3 times a day, you can cast the Plant Growth spell.

Realm Shift:  As a 2 hour ritual, you can use the residual power of Yggdrasil to travel to another plane.  Up to 10 creatures can be transported in this way.  After the ritual is complete the leaves wither and the branch loses all magical properties.  It is now nothing more than a stick.