diff --git modules/taxonomy/taxonomy.test modules/taxonomy/taxonomy.test
index 8b39414..604909f 100644
--- modules/taxonomy/taxonomy.test
+++ modules/taxonomy/taxonomy.test
@@ -987,6 +987,11 @@ class TaxonomyTermFieldTestCase extends TaxonomyWebTestCase {
     $entity->content = field_attach_view('test_entity', $entity, 'full');
     $this->content = drupal_render($entity->content);
     $this->assertText($term->name, t('Term name is displayed'));
+
+    // Delete the vocabulary and verify that the widget is gone.
+    taxonomy_vocabulary_delete($this->vocabulary->vid);
+    $this->drupalGet('test-entity/add/test-bundle');
+    $this->assertNoFieldByName("{$this->field_name}[$langcode]", '', t('Widget is not displayed'));
   }
 
   /**