The cork oak gives up its bark and grows it back again, so it is read as giving without being depleted. It also stands for buoyancy and a protective outer layer.
When this appeared in your dream, what were you feeling?
My Cosmic Code has a private dream journal. Write a dream down and the app picks out the symbols in it, shows what dream books say about them and, over time, which words recur across your entries. The journal is stored on your device only.