As you cling frantically to the tree, you sense that there is someone or something behind you.

Despite the wind and rain, you turn fearfully and look back.

You cling more tightly than ever to the tree, and refuse to look around. 

"Clinging to the tree", get it?

That's a bit obvious, don't you think? Especially in a story that has notably not clung to the tree mode.

If you insisted on a pure tree you'd be in danger of fallling into the ocean.