There is a collection of Dundjinni artwork available from the Vintyri Project here. I don't know if there are any trees in it, but I'm sure there must be

That collection at least will be covered by an EULA that is up to date and accessible, so that you can work out the right and wrong of everything without having to worry about documents that may no longer exist.

Bogie might be able to point you in a more specific direction.