diff --git a/sumpy/fmm.py b/sumpy/fmm.py
index 7c1894c43eb9af122e085f6e8c2d15ca5df7a249..2175fc5c8fa2efcb12d750a4f67ecda61957a60f 100644
--- a/sumpy/fmm.py
+++ b/sumpy/fmm.py
@@ -186,7 +186,7 @@ class SumpyExpansionWrangler(object):
         if not callable(fmm_level_to_order):
             raise TypeError("fmm_level_to_order not passed")
         self.level_orders = [
-                fmm_level_to_order(lev) for lev in range(tree.nlevels)]
+                fmm_level_to_order(tree, lev) for lev in range(tree.nlevels)]
 
         if kernel_extra_kwargs is None:
             kernel_extra_kwargs = {}