Seriva

"I'm Sorry, friend, but we're very busy. You might've heard about the big experiment today...? Masall!  Stop daydreaming!  Samples of Tiaran's bark and sap are priceless.  Bark samples need to be organized by date."

Location
can be found digging in the roots of Tiaran when you first arrive on the island and you can meet up with him later in Shadetree.