According to https://confluence.atlassian.com/display/CONF35/Pagetree+Macro#PagetreeMacro-AllParameters you can do the following:
Specifying the Parent Page by Name
Use the following code to specify a page name for the parent or root of the tree. The tree will include all children and grand-children of the specified root. The tree will not include the specified root page itself.
=> Try to just enter the pagename at "Root Page" in the pagetree admin area.
Hi team, I’m Avinoam, a product manager on Confluence Cloud, and today I’m really excited to let the Community know that all customers can now try out the new editing experience and see some of the ...
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