diff --git a/ostap/parallel/parallel_add_branch.py b/ostap/parallel/parallel_add_branch.py
index 2a0a0a5e..dd41da5a 100644
--- a/ostap/parallel/parallel_add_branch.py
+++ b/ostap/parallel/parallel_add_branch.py
@@ -98,6 +98,11 @@ def add_new_branch ( chain          ,
     wmgr     = WorkManager ( silent = not verbose , **kwargs )
     trees    = ch.split    ( max_files = 1  )
 
+    import ostap.parallel.parallel as P
+    print ( 'PARALLEL'  , p.worker , p.WorkManager , p.dill )
+    print ( 'PICKLES/F' , function    , P.pickles ( function    ) )
+    print ( 'PICKLES/B' , branch_name , P.pickles ( branch_name ) )
+    print ( 'PICKLES/T' , task        , P.pickles ( task  ) )
     
     wmgr.process ( task , trees )
 
diff --git a/ostap/trees/trees.py b/ostap/trees/trees.py
index fcb6cf8c..ccc5788e 100755
--- a/ostap/trees/trees.py
+++ b/ostap/trees/trees.py
@@ -1301,8 +1301,8 @@ def _rt_table_0_ ( tree ,
     if hasattr ( tree , 'pstatVar' ) : bbstats = tree.pstatVar ( bbs , cuts , *args )
     else                             : bbstats = tree. statVar ( bbs , cuts , *args )
 
-    from ostap.stats.counters import WSE 
-    if isinstance ( bbstats , WSE )  : bbstats = { bbs[0] : bbstats } 
+    from ostap.stats.counters import WSE, SE  
+    if   isinstance ( bbstats , ( WSE , SE ) )  : bbstats = { bbs[0] : bbstats } 
     
     for b in brs :