Worldtree Bloom

Source
This item is a potential reward from the following Class Hall missions:


 * Aw, Shucks!
 * Ripe for the Picking
 * Oh, Deer
 * Murky Waters
 * Harping On About It
 * Queen of Stone
 * Nightmare Ritual

It is also a quest reward from normal Val'sharah world quests and can be found inside Curious Wyrmtongue Cache.