Imagine you have this XML structure (copied from the documentation and shortened): <debug> <modules> <module>Finance</module> <module>Admin</module> <module>HR</module> </modules> </debug> Now imagine you have this function which you want to call three times to pass the <module>...</module> nodes to: void foo(boost::property_tree::ptree pt); You can use get_child("debug.modules") to retrieve a property tree containing all module nodes. However if you iterate over the property tree the iterator refers to std::pair<const key_type, basic_ptree<Tr>> - and there is no simple way to convert this pair to a new property tree. You must create an empty property tree followed by a call to push_back() to insert the pair. Either there is a conversion constructor missing or I miss something and there is a simpler way of what I'm trying to do? Boris