diff --git a/core/modules/taxonomy/src/TermStorage.php b/core/modules/taxonomy/src/TermStorage.php
index a1b460e..bd33bde 100644
--- a/core/modules/taxonomy/src/TermStorage.php
+++ b/core/modules/taxonomy/src/TermStorage.php
@@ -103,6 +103,7 @@ public function resetCache(array $ids = NULL) {
     $this->treeChildren = array();
     $this->treeParents = array();
     $this->treeTerms = array();
+    $this->trees = array();
     parent::resetCache($ids);
   }
 
@@ -458,7 +459,7 @@ public function getNodeTerms($nids, $vocabs = array(), $langcode = NULL) {
   public function __sleep() {
     $vars = parent::__sleep();
     // Do not serialize static cache.
-    unset($vars['parents'], $vars['parentsAll'], $vars['children'], $vars['treeChildren'], $vars['treeParents'], $vars['treeTerms']);
+    unset($vars['parents'], $vars['parentsAll'], $vars['children'], $vars['treeChildren'], $vars['treeParents'], $vars['treeTerms'], $var['trees']);
     return $vars;
   }
 
@@ -474,6 +475,7 @@ public function __wakeup() {
     $this->treeChildren = array();
     $this->treeParents = array();
     $this->treeTerms = array();
+    $this->trees = array();
   }
 
 }
diff --git a/core/modules/taxonomy/src/Tests/TermTest.php b/core/modules/taxonomy/src/Tests/TermTest.php
index 1fddcf8..a311045 100644
--- a/core/modules/taxonomy/src/Tests/TermTest.php
+++ b/core/modules/taxonomy/src/Tests/TermTest.php
@@ -474,7 +474,7 @@ function testTermReorder() {
     $this->assertEqual($terms[0]->id(), $term1->id(), 'Term 1 was moved to back above term 2.');
     $this->assertEqual($terms[1]->id(), $term2->id(), 'Term 2 was moved to back below term 1.');
     $this->assertEqual($terms[2]->id(), $term3->id(), 'Term 3 is still below term 2.');
-    $this->assertEqual($terms[2]->parents, array($term2->id()), 'Term 3 is still a child of term 2.' . var_export($terms[1]->id(), 1));
+    $this->assertEqual($terms[2]->parents, array($term2->id()), 'Term 3 is still a child of term 2.');
   }
 
   /**