I have 2 Mock Oranges (pittosporum) planted near one another in a morning sun spot in OC, CA. Both get the same ammount of water...one is happy the other looks like this...Does anyone know what could be wrong with it?
Help Pittosporum Not Well!
I read that there is an insect native to Asia: Xylosandrus compactus, a small bark beetle that digs tunnels inside the twigs, causing them to dry out.
Try dissecting a branch and see if it appears hollowed out.
In the meantime, as a precaution, I advise you to cut and burn the dry parts of the infested bush.