diff --git a/core/modules/forum/lib/Drupal/forum/Tests/ForumTest.php b/core/modules/forum/lib/Drupal/forum/Tests/ForumTest.php
index 290b257..040297f 100644
--- a/core/modules/forum/lib/Drupal/forum/Tests/ForumTest.php
+++ b/core/modules/forum/lib/Drupal/forum/Tests/ForumTest.php
@@ -240,8 +240,7 @@ function testForum() {
   function testAddOrphanTopic() {
     // Must remove forum topics to test creating orphan topics.
     $vid = config('forum.settings')->get('vocabulary');
-    $tree = taxonomy_get_tree($vid);
-    taxonomy_term_delete_multiple(array_keys(taxonomy_term_load_multiple(NULL)));
+    taxonomy_term_delete_multiple(array_keys(entity_load_multiple_by_properties('taxonomy_term', array('vid' => $vid))));
 
     // Create an orphan forum item.
     $this->drupalLogin($this->admin_user);
diff --git a/core/modules/path/lib/Drupal/path/Type/PathItem.php b/core/modules/path/lib/Drupal/path/Type/PathItem.php
new file mode 100644
index 0000000..fde8386
--- /dev/null
+++ b/core/modules/path/lib/Drupal/path/Type/PathItem.php
@@ -0,0 +1,43 @@
+<?php
+
+/**
+ * @file
+ * Contains \Drupal\path\Type\PathItem.
+ */
+
+namespace Drupal\path\Type;
+
+use Drupal\Core\Entity\Field\FieldItemBase;
+
+/**
+ * Defines the 'path_field' entity field item.
+ */
+class PathItem extends FieldItemBase {
+
+  /**
+   * Definitions of the contained properties.
+   *
+   * @see PathItem::getPropertyDefinitions()
+   *
+   * @var array
+   */
+  static $propertyDefinitions;
+
+  /**
+   * Implements \Drupal\Core\TypedData\ComplexDataInterface::getPropertyDefinitions().
+   */
+  public function getPropertyDefinitions() {
+
+    if (!isset(static::$propertyDefinitions)) {
+      static::$propertyDefinitions['alias'] = array(
+        'type' => 'string',
+        'label' => t('Path alias'),
+      );
+      static::$propertyDefinitions['pid'] = array(
+        'type' => 'integer',
+        'label' => t('Path id'),
+      );
+    }
+    return static::$propertyDefinitions;
+  }
+}
diff --git a/core/modules/path/path.module b/core/modules/path/path.module
index 2d5a03e..ee286f1 100644
--- a/core/modules/path/path.module
+++ b/core/modules/path/path.module
@@ -265,18 +265,46 @@ function path_form_taxonomy_term_form_alter(&$form, $form_state) {
 }
 
 /**
+ * Implements hook_data_type_info().
+ */
+function path_data_type_info() {
+  $info['path_field'] = array(
+    'label' => t('Path field item'),
+    'description' => t('An entity field containing a path alias and related data.'),
+    'class' => '\Drupal\path\Type\PathItem',
+    'list class' => '\Drupal\Core\Entity\Field\Type\Field',
+  );
+  return $info;
+}
+
+/**
+ * Implements hook_entity_field_info().
+ */
+function path_entity_field_info($entity_type) {
+  if ($entity_type == 'taxonomy_term') {
+    $info['definitions']['path'] = array(
+      'type' => 'path_field',
+      'label' => t('The path alias'),
+      'computed' => TRUE,
+      'list' => TRUE,
+    );
+    return $info;
+  }
+}
+
+/**
  * Implements hook_taxonomy_term_insert().
  */
 function path_taxonomy_term_insert(Term $term) {
+  debug($term->getPropertyDefinitions());
   if (isset($term->path)) {
-    $path = $term->path;
-    $path['alias'] = trim($path['alias']);
+    $term->path->alias = trim($term->path->alias);
     // Only save a non-empty alias.
-    if (!empty($path['alias'])) {
+    if (!empty($term->path->alias)) {
       // Ensure fields for programmatic executions.
-      $path['source'] = 'taxonomy/term/' . $term->id();
-      $path['langcode'] = LANGUAGE_NOT_SPECIFIED;
-      drupal_container()->get('path.crud')->save($path['source'], $path['alias'], $path['langcode']);
+      $source = 'taxonomy/term/' . $term->id();
+      $langcode = LANGUAGE_NOT_SPECIFIED;
+      drupal_container()->get('path.crud')->save($source, $term->path->alias, $langcode);
     }
   }
 }
@@ -286,19 +314,18 @@ function path_taxonomy_term_insert(Term $term) {
  */
 function path_taxonomy_term_update(Term $term) {
   if (isset($term->path)) {
-    $path = $term->path;
-    $path['alias'] = trim($path['alias']);
+    $term->path->alias = trim($term->path->alias);
     // Delete old alias if user erased it.
-    if (!empty($path['pid']) && empty($path['alias'])) {
-      drupal_container()->get('path.crud')->delete(array('pid' => $path['pid']));
+    if (!empty($term->path->pid) && empty($term->path->alias)) {
+      drupal_container()->get('path.crud')->delete(array('pid' => $term->path->pid));
     }
     // Only save a non-empty alias.
-    if (!empty($path['alias'])) {
-      $pid = (!empty($path['pid']) ? $path['pid'] : NULL);
+    if ($term->path->alias) {
+      $pid = (!empty($term->path->pid) ? $term->path->pid  : NULL);
       // Ensure fields for programmatic executions.
-      $path['source'] = 'taxonomy/term/' . $term->id();
-      $path['langcode'] = LANGUAGE_NOT_SPECIFIED;
-      drupal_container()->get('path.crud')->save($path['source'], $path['alias'], $path['langcode'], $pid);
+      $source = 'taxonomy/term/' . $term->id();
+      $langcode = LANGUAGE_NOT_SPECIFIED;
+      drupal_container()->get('path.crud')->save($source, $term->path->alias, $langcode, $pid);
     }
   }
 }
diff --git a/core/modules/taxonomy/lib/Drupal/taxonomy/Plugin/Core/Entity/Term.php b/core/modules/taxonomy/lib/Drupal/taxonomy/Plugin/Core/Entity/Term.php
index 40a3ac3..e9408a0 100644
--- a/core/modules/taxonomy/lib/Drupal/taxonomy/Plugin/Core/Entity/Term.php
+++ b/core/modules/taxonomy/lib/Drupal/taxonomy/Plugin/Core/Entity/Term.php
@@ -114,7 +114,6 @@ class Term extends EntityNG implements ContentEntityInterface {
   protected $values = array(
     'langcode' => array(LANGUAGE_DEFAULT => array(0 => array('value' => LANGUAGE_NOT_SPECIFIED))),
     'weight' => array(LANGUAGE_DEFAULT => array(0 => array('value' => 0))),
-    'parent' => array(LANGUAGE_DEFAULT => array(0 => array('value' => 0))),
   );
 
   /**
diff --git a/core/modules/taxonomy/lib/Drupal/taxonomy/Plugin/views/field/TaxonomyIndexTid.php b/core/modules/taxonomy/lib/Drupal/taxonomy/Plugin/views/field/TaxonomyIndexTid.php
index 18f458b..179f019 100644
--- a/core/modules/taxonomy/lib/Drupal/taxonomy/Plugin/views/field/TaxonomyIndexTid.php
+++ b/core/modules/taxonomy/lib/Drupal/taxonomy/Plugin/views/field/TaxonomyIndexTid.php
@@ -120,14 +120,14 @@ function pre_render(&$values) {
       $result = $query->execute();
 
       foreach ($result as $term) {
-        $this->items[$term->node_nid][$term->id()]['name'] = check_plain($term->label());
-        $this->items[$term->node_nid][$term->id()]['tid'] = $term->id();
-        $this->items[$term->node_nid][$term->id()]['vocabulary_vid'] = $term->bundle();
-        $this->items[$term->node_nid][$term->id()]['vocabulary'] = check_plain($vocabularies[$term->bundle()]->label());
+        $this->items[$term->node_nid][$term->tid]['name'] = check_plain($term->name);
+        $this->items[$term->node_nid][$term->tid]['tid'] = $term->tid;
+        $this->items[$term->node_nid][$term->tid]['vocabulary_vid'] = $term->vid;
+        $this->items[$term->node_nid][$term->tid]['vocabulary'] = check_plain($vocabularies[$term->vid]->label());
 
         if (!empty($this->options['link_to_taxonomy'])) {
-          $this->items[$term->node_nid][$term->id()]['make_link'] = TRUE;
-          $this->items[$term->node_nid][$term->id()]['path'] = 'taxonomy/term/' . $term->id();
+          $this->items[$term->node_nid][$term->tid]['make_link'] = TRUE;
+          $this->items[$term->node_nid][$term->tid]['path'] = 'taxonomy/term/' . $term->tid;
         }
       }
     }
diff --git a/core/modules/taxonomy/lib/Drupal/taxonomy/Plugin/views/filter/TaxonomyIndexTid.php b/core/modules/taxonomy/lib/Drupal/taxonomy/Plugin/views/filter/TaxonomyIndexTid.php
index cc69b4f..856254a 100644
--- a/core/modules/taxonomy/lib/Drupal/taxonomy/Plugin/views/filter/TaxonomyIndexTid.php
+++ b/core/modules/taxonomy/lib/Drupal/taxonomy/Plugin/views/filter/TaxonomyIndexTid.php
@@ -140,7 +140,7 @@ function value_form(&$form, &$form_state) {
         if ($tree) {
           foreach ($tree as $term) {
             $choice = new stdClass();
-            $choice->option = array($term->id() => str_repeat('-', $term->depth) . $term->name);
+            $choice->option = array($term->tid => str_repeat('-', $term->depth) . $term->name);
             $options[] = $choice;
           }
         }
@@ -158,7 +158,7 @@ function value_form(&$form, &$form_state) {
         }
         $result = $query->execute();
         foreach ($result as $term) {
-          $options[$term->id()] = $term->name;
+          $options[$term->tid] = $term->name;
         }
       }
 
@@ -320,7 +320,7 @@ function validate_term_strings(&$form, $values) {
     $result = $query->execute();
     foreach ($result as $term) {
       unset($missing[strtolower($term->name)]);
-      $tids[] = $term->id();
+      $tids[] = $term->tid;
     }
 
     if ($missing && !empty($this->options['error_message'])) {
@@ -360,7 +360,7 @@ public function adminSummary() {
         ->condition('td.tid', $this->value)
         ->execute();
       foreach ($result as $term) {
-        $this->value_options[$term->id()] = $term->name;
+        $this->value_options[$term->tid] = $term->name;
       }
     }
     return parent::adminSummary();
diff --git a/core/modules/taxonomy/lib/Drupal/taxonomy/TermStorageController.php b/core/modules/taxonomy/lib/Drupal/taxonomy/TermStorageController.php
index b5690c0..b75b229 100644
--- a/core/modules/taxonomy/lib/Drupal/taxonomy/TermStorageController.php
+++ b/core/modules/taxonomy/lib/Drupal/taxonomy/TermStorageController.php
@@ -24,6 +24,9 @@ class TermStorageController extends DatabaseStorageControllerNG {
    *   vocabulary ID ('vid') is required.
    */
   public function create(array $values) {
+    if (empty($values['parent'])) {
+      $values['parent'] = array(0);
+    }
     $entity = parent::create($values);
     return $entity;
   }
@@ -83,20 +86,27 @@ protected function postDelete($entities) {
    * Overrides Drupal\Core\Entity\DatabaseStorageController::postSave().
    */
   protected function postSave(EntityInterface $entity, $update) {
-    db_delete('taxonomy_term_hierarchy')
-      ->condition('tid', $entity->id())
-      ->execute();
+    // Only change the parents if a value is set, keep the existing values if
+    // not. They are keyed by term id if set through the UI, so take the first
+    // value.
+    $parents = $entity->parent->getValue();
+    $parent = reset($parents);
+    if (isset($parent['value']) && $parent['value'] !== NULL) {
+      db_delete('taxonomy_term_hierarchy')
+        ->condition('tid', $entity->id())
+        ->execute();
 
-    $query = db_insert('taxonomy_term_hierarchy')
-      ->fields(array('tid', 'parent'));
+      $query = db_insert('taxonomy_term_hierarchy')
+        ->fields(array('tid', 'parent'));
 
-    foreach ($entity->parent as $parent) {
-      $query->values(array(
-        'tid' => $entity->id(),
-        'parent' => (int)$parent->value,
-      ));
+      foreach ($entity->parent as $parent) {
+        $query->values(array(
+          'tid' => $entity->id(),
+          'parent' => (int)$parent->value,
+        ));
+      }
+      $query->execute();
     }
-    $query->execute();
   }
 
   /**
diff --git a/core/modules/taxonomy/taxonomy.pages.inc b/core/modules/taxonomy/taxonomy.pages.inc
index 31146f7..db12e91 100644
--- a/core/modules/taxonomy/taxonomy.pages.inc
+++ b/core/modules/taxonomy/taxonomy.pages.inc
@@ -22,9 +22,10 @@ function taxonomy_term_page(Term $term) {
   // @todo This overrides any other possible breadcrumb and is a pure hard-coded
   //   presumption. Make this behavior configurable per vocabulary or term.
   $breadcrumb = array();
-  while ($parents = taxonomy_term_load_parents($term->id())) {
-    $term = array_shift($parents);
-    $breadcrumb[] = l($term->label(), 'taxonomy/term/' . $term->id());
+  $current = $term;
+  while ($parents = taxonomy_term_load_parents($current->id())) {
+    $current = array_shift($parents);
+    $breadcrumb[] = l($term->label(), 'taxonomy/term/' . $current->id());
   }
   $breadcrumb[] = l(t('Home'), NULL);
   $breadcrumb = array_reverse($breadcrumb);