Best bet would be Willow Tree Vines since Tarzan lived in Africa, it would not be a banana vine or other tropical vine. "African pictures of willows trees, weeping, creeping peeping, quote the raven - Whaaaaaaaaa! Shmock, shmock! Ah-woo! Ah-woo! Vines criss-cross the mangrove like so many phone wires in a wireless civilization, lost in the realization. " [Not sure if this came from Tarzan comic issue #2, Dell Comics http://www.erbzine.com/mag15/1598b.html] Picture of http://willowboard.net/

the oxford advanced learner's dictionary includes the term "liana". so, the term is correct. note that zaina uses the term "vine" in her explanation. so, it seems that the only thing is to check what word is more average for the english speaking people. (zaina you just keep me amazed!).

In India we have a similar kind of tree that is shown in Tarzan movies...its name is Banyan tree..it has long n strong stems.You can hold the vines in ur palm n make a tight grip to climb n jump from one to other stem.

we simple call it VINE. the grape plant is a small kind of vine, but i dont think tarzan can use grape vine to swing! lol.

we say liana in spanish. pronounced lee-a-nah. etimologilcally liana comes from the same esteem as "liar" a verb which means "to embroil" for threads, normally. the verb also applies when you want to mean that something is an imboglio or when you get into no "licit" relation with other persons (in bussiness, in illegal deeds, in not serious relations with opposite sex and some other activities not made bona fide.