Vespid

Long ago, the Vespids suppressed the power of the Tree, laying upon it a curse of dormancy, shrouding its existence from the rest of the dungeon. Before she transformed and became a Vespid, Melora was once a dryad herself. She turned her back on the Circle, destroyed the Dryads' trees, which sent the Dryads into a state of slumber that lasted to this day. It was due to their connection with the Tree that they were able to survive the slaughter of their trees.

Because of a reason that will be discovered later the tree and dryad awaken and kill/destory the Vespid hive.

With the Vespids gone, their tight grip on the sun crystals are no more. Indeed, now that that grip has slackened, it becomes clear that Melora's control had more of an impact that just on the economy. Liberation of the sun crystals brings on a new wave of liveliness from the plants as the light shines brighter than ever before. It seems Melora was suppressing the full power of the sun crystals, making the plants more somnolent and lethargic.