Mahogany trees in runescape!?

hey runescape players! I've got 50 woodcutting lvl! but i really need to get 2 lvl 60! so i can get yew's but wen i go to karamja n go to the place were u pay 100 trading sticks i try to chop ether 1 of the 2 types of trees that grow there (Mahogany&teak) it says that i need to clean up "tai bwo wannai" i don't understand i olredy did the quest "jungle potion" i really need the experiance! any help on how i can get them?!?