diff --git a/src/main/java/info/textgrid/services/aggregator/tree/AggregationTreeFactory.java b/src/main/java/info/textgrid/services/aggregator/tree/AggregationTreeFactory.java
index b5c850c2384d7e50823a9e9cd3b9e47d34d58ca3..0a43829b044eaf0cbe83ac4b3e942cfb2395946d 100644
--- a/src/main/java/info/textgrid/services/aggregator/tree/AggregationTreeFactory.java
+++ b/src/main/java/info/textgrid/services/aggregator/tree/AggregationTreeFactory.java
@@ -37,4 +37,12 @@ protected void walkAggregation(final ObjectType aggregation,
 		stack.pop();
 	}
 
+	protected Aggregation getRoot() {
+		return root;
+	}
+
+	public static Aggregation create(final ObjectType root) {
+		return new AggregationTreeFactory(root).getRoot();
+	}
+
 }