 			jsonCache.getJsonObject(getUrl(method, params), resultHandler, faultHandler);
 		}
 		
-		public function createCategoryNode(data:Object = null):ColumnTreeNode
+		override protected function refreshHierarchy():void
 		{
-			if (!data)
-			{
-				var name:String = WeaveAPI.globalHashMap.getName(this);
-				data = {id: 0, name: name};
-			}
-			return new ColumnTreeNode({
-				dataSource: this,
-				data: data,
-				label: data.name,
-				hasChildBranches: true,
-				children: function(node:ColumnTreeNode):Array {
-					var children:Array = [];
-					getJson('category/children', {category_id: node.data.id}, function(result:Object):void {
-						var nodes:Array = [];
-						for each (var item:Object in result.categories)
-							nodes.push(createCategoryNode(item));
-						// put categories first in the list
-						children.splice.apply(null, [0, 0].concat(nodes));
-					});
-					getJson('category/series', {category_id: node.data.id}, function(result:Object):void {
-						for each (var item:Object in result.seriess)
-							children.push(createSeriesNode(item));
-					});
-					return children;
-				}
-			});
-		}
-		
-		override protected function refreshHierarchy():void
-		{
-			for each (var csv:CSVDataSource in csvCache)
-				disposeObject(csv);
-			csvCache = {};
+			for each (var csv:CSVDataSource in csvCache)
+				disposeObject(csv);
+			csvCache = {};
 		}
 		
 		private var csvCache:Object = {};

			
			return new ColumnTreeNode({
				dataSource: this,
				idFields: META_ID_FIELDS,
				data: metadata
			});
		}
        
        override protected function requestColumnFromSource(proxyColumn:ProxyColumn):void
        {
            var series:String = proxyColumn.getMetadata(META_SERIES_ID);

    {
        WeaveAPI.ClassRegistry.registerImplementation(IDataSource, FREDDataSource, "Federal Reserve Economic Data");

		private const jsonCache:JsonCache = newLinkableChild(this, JsonCache);
		
		public const apiKey:LinkableString = registerLinkableChild(this, new LinkableString("fa99c080bdbd1d486a55e7cb6ab7acbb"));
