Cassa Tree
A cassa tree is a kind of tree growing on the island of Pingaree, with branches low and wide enough to shelter under.
First named in Rinkitink in Oz, ch. 4
the three wanderers crept beneath the overhanging branches of a cassa tree
What the books say it is
appearance overhanging branches 1 chapter
Since no house remained standing, in which they might sleep, the three wanderers crept beneath the overhanging branches of a cassa tree and curled themselves up as comfortably as possible.
Rinkitink in Oz, ch. 4