diff --git a/admin/code/LeftAndMain.php b/admin/code/LeftAndMain.php
index 7ec4b764c..a67058496 100644
--- a/admin/code/LeftAndMain.php
+++ b/admin/code/LeftAndMain.php
@@ -535,7 +535,7 @@ class LeftAndMain extends Controller {
 				$treeTitle = '...';
 			}
 			
-			$html = "<ul id=\"sitetree\" class=\"tree unformatted\"><li id=\"record-0\" data-id=\"0\"class=\"Root nodelete\"><a href=\"$rootLink\"><strong>$treeTitle</strong></a>"
+			$html = "<ul><li id=\"record-0\" data-id=\"0\"class=\"Root nodelete\"><a href=\"$rootLink\"><strong>$treeTitle</strong></a>"
 				. $html . "</li></ul>";
 		}
 
diff --git a/admin/javascript/LeftAndMain.AddForm.js b/admin/javascript/LeftAndMain.AddForm.js
index 3149ca108..f65526d3c 100644
--- a/admin/javascript/LeftAndMain.AddForm.js
+++ b/admin/javascript/LeftAndMain.AddForm.js
@@ -40,7 +40,7 @@
 		
 				Observable.applyTo(this[0]);
 		
-				var tree = $('#sitetree');
+				var tree = $('.cms-tree');
 				this.setTree(tree);
 				
 				// Event bindings
diff --git a/admin/javascript/LeftAndMain.BatchActions.js b/admin/javascript/LeftAndMain.BatchActions.js
index 5e9afbb43..ead11b008 100644
--- a/admin/javascript/LeftAndMain.BatchActions.js
+++ b/admin/javascript/LeftAndMain.BatchActions.js
@@ -36,7 +36,7 @@
 			 * Constructor: onmatch
 			 */
 			onmatch: function() {
-				var self = this, tree = $('#sitetree');
+				var self = this, tree = $('.cms-tree');
 				
 				this.setTree(tree);
 				
diff --git a/admin/javascript/LeftAndMain.Tree.js b/admin/javascript/LeftAndMain.Tree.js
index a215f06ad..86cf66f56 100755
--- a/admin/javascript/LeftAndMain.Tree.js
+++ b/admin/javascript/LeftAndMain.Tree.js
@@ -6,7 +6,7 @@
 	
 	$.entwine('ss', function($){
 	
-		$('#sitetree').entwine({
+		$('.cms-tree').entwine({
 			onmatch: function() {
 				this._super();
 				
@@ -264,7 +264,7 @@
 		});
 	});
 	
-	$('#sitetree.multiple').entwine({
+	$('.cms-tree.multiple').entwine({
 		onmatch: function() {
 			this._super();
 			
@@ -286,7 +286,7 @@
 		}
 	});
 	
-	$('#sitetree li').entwine({
+	$('.cms-tree li').entwine({
 		
 		/**
 		 * Function: setEnabled
diff --git a/admin/javascript/SecurityAdmin.js b/admin/javascript/SecurityAdmin.js
index b17235113..7607cfa34 100755
--- a/admin/javascript/SecurityAdmin.js
+++ b/admin/javascript/SecurityAdmin.js
@@ -12,7 +12,7 @@
 			if(memberTableField) memberTableField.refresh();
 			
 			// Refresh tree
-			var tree = $(window.parent.document).find('#sitetree').get(0);
+			var tree = $(window.parent.document).find('.cms-tree').get(0);
 			if(tree) tree.reload();
 		}
 	};
diff --git a/admin/templates/Includes/SecurityAdmin_left.ss b/admin/templates/Includes/SecurityAdmin_left.ss
index 29c660a57..bdf2a0c7c 100644
--- a/admin/templates/Includes/SecurityAdmin_left.ss
+++ b/admin/templates/Includes/SecurityAdmin_left.ss
@@ -36,7 +36,7 @@
 			</label>
 		</div>
 
-		<div id="sitetree" data-url-tree="$Link(getsubtree)" data-url-savetreenode="$Link(savetreenode)" class="jstree jstree-apple">
+		<div data-url-tree="$Link(getsubtree)" data-url-savetreenode="$Link(savetreenode)" class="cms-tree jstree jstree-apple">
 			$SiteTreeAsUL
 		</div>
 		
diff --git a/docs/en/topics/extending-the-cms.md b/docs/en/topics/extending-the-cms.md
deleted file mode 100644
index a2007092f..000000000
--- a/docs/en/topics/extending-the-cms.md
+++ /dev/null
@@ -1,65 +0,0 @@
-# Extending the CMS
-
-CMSMain is part of the CMS.  It is the controller for the content editor.
-
-## Creating another hierarchical editor by subclassing CMSMain
-
-Sometimes you'll want to provide an administration interface that is pretty much exactly what CMSMain provides, but it's
-not appropriate to include your data in with the site content.
-
-Here's how you can do this:
-
-## Using classes other than SiteTree in the site tree
-
-It is possible to use to different classes in two separate site trees. For example, there is the usual site
-content tree and a category tree. To change that find:
-
-	:::php
-	static $tree_class = 'SiteTree';
-
-And change the string to the name of the class that will be the base class for classes visible in the site tree.
-
-
-## Overloading page urls
-
-If using a url other than admin/ for your section then you will need to change the SiteTreeHandlers to use the correct
-controller.
-
-Create the init method:
-
-	:::php
-	function init() { 
-		parent::init(); 
-		Requirements::javascript('project-name/javascript/Classname_left.js'); 
-	}
-
-Where project-name and Classname are changed as appropriate.
-
-Create the javascript file and add the handlers:
-
-	:::php
-	if(typeof SiteTreeHandlers == 'undefined') SiteTreeHandlers = {};
-	SiteTreeHandlers.parentChanged_url = 'url/ajaxupdateparent';
-	SiteTreeHandlers.orderChanged_url = 'url/ajaxupdatesort';
-	SiteTreeHandlers.showRecord_url = 'url/show/';
-	SiteTreeHandlers.loadPage_url = 'url/show/';
-	SiteTreeHandlers.loadTree_url = 'url/getsubtree';
-
-where url is the relative link to the page (eg 'admin/categories'). You can change the handler functions as necessary.
-
-## Overloading EditForm
-
-You may need to overload EditForm if your class does not use the `[api:Versioned]` extension.
-
-## Overloading SiteTreeAsUL
-
-The tree hints can sometimes cause problems when reorganising the tree, and the CMSMain::SiteTreeAsUL function uses
-`[api:SiteTree]` explicitly. Use:
-
-	:::php
-	public function SiteTreeAsUL() {
-		// $this->generateDataTreeHints();
-		$this->generateTreeStylingJS();
-	
-		return $this->getSiteTreeFor( $this->stat('tree_class') );
-	}
diff --git a/docs/en/topics/javascript.md b/docs/en/topics/javascript.md
index 4750e4a81..db08c3f74 100644
--- a/docs/en/topics/javascript.md
+++ b/docs/en/topics/javascript.md
@@ -602,7 +602,7 @@ The CMS has a number of Observer-pattern hooks you can access: (The elements whi
   * BeforeSave -- after user clicks 'Save', before AJAX save-request (#Form_EditForm)
   * PageLoaded -- after new SiteTree page is loaded. (#Form_EditForm)
   * PageSaved -- after AJAX save-request is successful (#Form_EditForm)
-  * SelectionChanged -- when new item is chosen from SiteTree (#sitetree)
+  * SelectionChanged -- when new item is chosen from SiteTree (.cms-tree)
 
 Here's an example of hooking the 'PageLoaded' and 'BeforeSave' methods: