diff --git a/lib/dm-serializer/to_xml.rb b/lib/dm-serializer/to_xml.rb
index 2b572eb..a18fafd 100644
--- a/lib/dm-serializer/to_xml.rb
+++ b/lib/dm-serializer/to_xml.rb
@@ -102,7 +102,7 @@ def to_xml_document(opts = {})
         DataMapper::Inflector.pluralize(DataMapper::Inflector.underscore(self.model.to_s)).tr("/", "-")
       }
 
-      root = xml.root_node(
+      xml.root_node(
         doc,
         opts[:collection_element_name] || default_collection_element_name[],
         {'type' => 'array'}