Please see the attached example. If I call 
org-table-iterate-buffer-tables, Summary1 and Summary2 both are 
calculated using the referenced tables in heading "first set of tables" 
and the tables in the second heading are disregarded.

Without going into the details there are times when I use certain form 
tables in separate headlines in the same file. The entries are different 
in each and I believe that a function perhaps 
"org-table-iterate-subtree-tables" would be a useful addition to 
org-table.el.

Please note that narrowing the buffer to the second headline does not 
help since the code in org-table-iterate-buffer-tables widens the buffer.

Charlie Millar