Thank you for writing.
There is no such method in RadTreeView for WinForms. In order to get all nodes, you should traverse them recursively. Here is an example:
//do smth with the node
(node.Nodes.Count > 0)
I hope this helps. Please note that in Q1 2011 we have introduced a fully refactored version of RadTreeView with many improvements and additions. Feel free to download the latest release and try it.
the Telerik team