Did you mean Normal tree?
A tree is a piece of scenery found in southern exotic areas of Gielinor, like Karamja and Yanille. There is no way to interact with it other than to examine it.
Two trees form an entrance to Rashiliyia's Tomb in Karamja, east of Ship yard. The trees can be searched to reveal doors called Hillside Entrance. A Bone Key is required to open the entrance.