wanted to share this response that I received from Wayne in Hawaii.....

The shriveled stems of plumeria is an indication that somehow moisture isnÂt getting to the stems. So, somewhere between the stems and where the water is picked up, the vascular system is not functioning properly. The roots, as IÂm sure you know, is what picks water up. Normally, roots are white (when alive).
I suspect that the roots are probably dead or dying. This is the first thing I would check. If so, then determining what killed the roots is the next step, but it is not easy. Root die back can be caused by overwatering, over fertilizing, inadequate oxygen (poor drainage), in adequate moisture, insects, diseases, pesticides, and other causes.If not the roots, then you need to take a look where the roots connect to the stem and see if the basal stem is intact, if OK, then need to continue moving upwards.
Again, I suspect the problem is with the root system.

since I have this plumeria in a pot which is half way in the ground from what Wayne states above...the roots are probably root bound....so I will break the pot without disturbing the tree and should be ok...