Q.Plumaria: dead or alive
Mu Plumaria started showing some oily spots last fall, with some Brown discoloration towards the base. Now almost the entire base has a terrible blackish coloring, some areas looks really thick. The stems of the upper tree have withered.
Should i consider this tree to be dead?

Unfortunately I this looks like an infestation. It appears to be that the stalks of the plumeria have small holes oozing a black substance. This is a sign of longhorn borer infestation, and infected limbs should be cut off the tree and burned immediately. Although the holes may not be actively oozing in the dormant season, cut away any bent and shriveled limbs with these holes at the base during winter pruning.