Is there an example of loading hierarchical data into a tree store using an XML reader? The reason why I ask is because the method Ext.data.reader.Xml::getRoot() is failing when the call to Ext.DomQuery.isXml() is called. The error states that the method Ext.DomQuery.isXml() does not exist. Upon learning that I overrided the method and removed the conditional making the conditional a mere else but now receive an error stating the method querySelectorAll does not exist on passed object (root object which is an object literal - makes sense). So it seems to me looking at the comments that someone anticipated the possibility of root node for a tree store not being a dom node but has not fully implemented it yet in regards to Ext.DomQuery.selectNode() is that the case? I'll look at it a little further though.