When a user clicks on a tree item to link to a URL, the cftreeItemKey variable, which identifies the selected value, is appended to the URL in the following form:
http://myserver.com?CFTREEITEMKEY=selected_item_value_attribute
If the value attribute includes spaces, ColdFusion replaces the spaces with plus characters (+).
Automatically passing the name of the selected tree item as part of the URL makes it easy to implement a basic "drill down" application that displays additional information based on the selection. For example, if the specified URL is another ColdFusion page, it can access the selected value as the variable URL.CFTREEITEMKEY.
To disable this behavior, set the appendkey attribute in the cftree tag to No.