diff --git a/src/libraries/JANA/JFactoryT.h b/src/libraries/JANA/JFactoryT.h
index 2e6eddf86..30252b3b6 100644
--- a/src/libraries/JANA/JFactoryT.h
+++ b/src/libraries/JANA/JFactoryT.h
@@ -25,7 +25,7 @@ class JFactoryT : public JFactory {
     using IteratorType = typename std::vector<T*>::const_iterator;
     using PairType = std::pair<IteratorType, IteratorType>;
 
-    JFactoryT() : JFactory(JTypeInfo::demangle<T>(), ""){
+    JFactoryT(std::string tag="") : JFactory(JTypeInfo::demangle<T>(), tag){
         EnableGetAs<T>();
         EnableGetAs<JObject>( std::is_convertible<T,JObject>() ); // Automatically add JObject if this can be converted to it
 #if JANA2_HAVE_ROOT