diff --git a/gtsam/inference/BayesTree-inst.h b/gtsam/inference/BayesTree-inst.h
index 7a88e37f6..b3fc8cb4c 100644
--- a/gtsam/inference/BayesTree-inst.h
+++ b/gtsam/inference/BayesTree-inst.h
@@ -416,7 +416,7 @@ namespace gtsam {
       child->parent_ = typename Clique::weak_ptr();
 
     BOOST_FOREACH(Key j, clique->conditional()->frontals()) {
-      nodes_.erase(j);
+      nodes_.unsafe_erase(j);
     }
   }
 
@@ -495,7 +495,7 @@ namespace gtsam {
 
       // Remove this node from the nodes index
       BOOST_FOREACH(Key j, (*clique)->conditional()->frontals()) {
-        nodes_.erase(j); }
+        nodes_.unsafe_erase(j); }
 
       // Erase the parent and children pointers
       (*clique)->parent_.reset();
diff --git a/gtsam/nonlinear/ISAM2-impl.cpp b/gtsam/nonlinear/ISAM2-impl.cpp
index 8da8bf29e..38c087741 100644
--- a/gtsam/nonlinear/ISAM2-impl.cpp
+++ b/gtsam/nonlinear/ISAM2-impl.cpp
@@ -55,7 +55,7 @@ void ISAM2::Impl::RemoveVariables(const FastSet<Key>& unusedKeys, const FastVect
     deltaNewton.erase(key);
     RgProd.erase(key);
     replacedKeys.erase(key);
-    nodes.erase(key);
+    nodes.unsafe_erase(key);
     theta.erase(key);
     fixedVariables.erase(key);
   }