diff --git a/generator/classes/propel/engine/database/model/Table.php b/generator/classes/propel/engine/database/model/Table.php
index <HASH>..<HASH> 100644
--- a/generator/classes/propel/engine/database/model/Table.php
+++ b/generator/classes/propel/engine/database/model/Table.php
@@ -997,6 +997,12 @@ class Table extends XMLElement implements IDMethod {
                   . '"';
         }
 
+        if ($this->isTree) {
+            $result .= " isTree=\""
+                  . ($this->isTree ? "true" : "false")
+                  . '"';
+        }
+
         if ($this->abstractValue) {
             $result .= " abstract=\""
                   . ($abstractValue ? "true" : "false")
@@ -1094,4 +1100,4 @@ class Table extends XMLElement implements IDMethod {
         }
         return $result;
     }
-}
\ No newline at end of file
+}
added isTree attribute to xml generated by toString See:#<I>