The buad tea is in verdistis. It is in the seller under the potionman. You have to open the hatch (lvl 5 lockpick!) its under a bed(very hard to see though). Then take a CLOSED barrel and trow it at tree. (nice tresury, some silver and gold charm and a beetle statue).
Actually you dont need to kill the tree. Atleast dont do it before you have both quest conected to the tree!!
