diff --git a/core/lib/Drupal/Core/Entity/Entity.php b/core/lib/Drupal/Core/Entity/Entity.php
index d3b5c41..0f95e21 100644
--- a/core/lib/Drupal/Core/Entity/Entity.php
+++ b/core/lib/Drupal/Core/Entity/Entity.php
@@ -465,6 +465,15 @@ public function validate() {
   }
 
   /**
+   * {@inheritdoc}
+   */
+  public function applyDefaultValue($notify = TRUE) {
+    foreach ($this->getProperties() as $property) {
+      $property->applyDefaultValue(FALSE);
+    }
+  }
+
+  /**
    * Implements \Drupal\Core\TypedData\ComplexDataInterface::onChange().
    */
   public function onChange($property_name) {
diff --git a/core/lib/Drupal/Core/Entity/EntityBCDecorator.php b/core/lib/Drupal/Core/Entity/EntityBCDecorator.php
index 9697648..00c4654 100644
--- a/core/lib/Drupal/Core/Entity/EntityBCDecorator.php
+++ b/core/lib/Drupal/Core/Entity/EntityBCDecorator.php
@@ -523,4 +523,11 @@ public function onChange($property_name) {
   public function isTranslatable() {
     return $this->decorated->isTranslatable();
   }
+
+  /**
+   * Forwards the call to the decorated entity.
+   */
+  public function applyDefaultValue($notify = TRUE) {
+    return $this->decorated->applyDefaultValue($notify);
+  }
 }
diff --git a/core/lib/Drupal/Core/Entity/Field/FieldItemBase.php b/core/lib/Drupal/Core/Entity/Field/FieldItemBase.php
index 2c3feef..eb94b20 100644
--- a/core/lib/Drupal/Core/Entity/Field/FieldItemBase.php
+++ b/core/lib/Drupal/Core/Entity/Field/FieldItemBase.php
@@ -91,6 +91,7 @@ public function set($property_name, $value, $notify = TRUE) {
     // value that needs to be updated.
     if (isset($this->properties[$property_name])) {
       $this->properties[$property_name]->setValue($value, FALSE);
+      unset($this->values[$property_name]);
     }
     // Allow setting plain values for not-defined properties also.
     else {
diff --git a/core/lib/Drupal/Core/Entity/Field/Type/EntityReferenceItem.php b/core/lib/Drupal/Core/Entity/Field/Type/EntityReferenceItem.php
index 5b78a05..f568aec 100644
--- a/core/lib/Drupal/Core/Entity/Field/Type/EntityReferenceItem.php
+++ b/core/lib/Drupal/Core/Entity/Field/Type/EntityReferenceItem.php
@@ -87,15 +87,19 @@ public function __isset($property_name) {
    * Overrides \Drupal\Core\Entity\Field\FieldItemBase::get().
    */
   public function setValue($values, $notify = TRUE) {
-    // Treat the values as property value of the entity property, if no array is
-    // given.
+    // Treat the values as value of the entity property, if no array is
+    // given as this handles entity IDs and objects.
     if (isset($values) && !is_array($values)) {
-      $values = array('entity' => $values);
+      // Directly update the property instead of invoking the parent, so that
+      // the entity property can take care of updating the ID property.
+      $this->properties['entity']->setValue($values, $notify);
     }
-    // Make sure that the 'entity' property gets set as 'target_id'.
-    if (isset($values['target_id']) && !isset($values['entity'])) {
-      $values['entity'] = $values['target_id'];
+    else {
+      // Make sure that the 'entity' property gets set as 'target_id'.
+      if (isset($values['target_id']) && !isset($values['entity'])) {
+        $values['entity'] = $values['target_id'];
+      }
+      parent::setValue($values, $notify);
     }
-    parent::setValue($values, $notify);
   }
 }
diff --git a/core/lib/Drupal/Core/Entity/Field/Type/Field.php b/core/lib/Drupal/Core/Entity/Field/Type/Field.php
index f3a8866..3f89f97 100644
--- a/core/lib/Drupal/Core/Entity/Field/Type/Field.php
+++ b/core/lib/Drupal/Core/Entity/Field/Type/Field.php
@@ -22,8 +22,7 @@
  * directly to the first item.
  *
  * Supported settings (below the definition's 'settings' key) are:
- * - default_value: (optional) If set, the default value to apply to the first
- *   item of the field.
+ * - default_value: (optional) If set, the default value to apply to the field.
  *
  * @see \Drupal\Core\Entity\Field\FieldInterface
  */
@@ -207,16 +206,15 @@ public function defaultAccess($operation = 'view', User $account = NULL) {
   }
 
   /**
-   * Overrides \Drupal\Core\TypedData\TypedDataInterface::applyDefaultValue().
+   * {@inheritdoc}
    */
-  public function applyDefaultValue() {
+  public function applyDefaultValue($notify = TRUE) {
     if (isset($this->definition['settings']['default_value'])) {
-      $value = $this->definition['settings']['default_value'];
-      // Create one field item with the value provided.
-      $this->setValue(array(0 => $value));
+      $this->setValue($this->definition['settings']['default_value'], $notify);
     }
     else {
-      $this->setValue(NULL);
+      // Create one field item and apply defaults.
+      $this->offsetGet(0)->applyDefaultValue(FALSE);
     }
     return $this;
   }
diff --git a/core/lib/Drupal/Core/Entity/Field/Type/LanguageField.php b/core/lib/Drupal/Core/Entity/Field/Type/LanguageField.php
deleted file mode 100644
index 485995f..0000000
--- a/core/lib/Drupal/Core/Entity/Field/Type/LanguageField.php
+++ /dev/null
@@ -1,31 +0,0 @@
-<?php
-
-/**
- * @file
- * Contains \Drupal\Core\Entity\Field\Type\LanguageField.
- */
-
-namespace Drupal\Core\Entity\Field\Type;
-
-/**
- * Defines a field class for the 'language_field' entity field.
- *
- * Supported settings (below the definition's 'settings' key) are:
- * - default_value: (optional) If set, the default value to apply to the first
- *   item of the field. Else, the field defaults to LANGUAGE_NOT_SPECIFIED.
- */
-class LanguageField extends Field {
-
-  /**
-   * Overrides Field::applyDefaultValue().
-   */
-  public function applyDefaultValue() {
-    // Default to one field item with the value of LANGUAGE_NOT_SPECIFIED.
-    $value = array('value' => LANGUAGE_NOT_SPECIFIED);
-    if (isset($this->definition['settings']['default_value'])) {
-      $value = $this->definition['settings']['default_value'];
-    }
-    $this->setValue(array(0 => $value));
-    return $this;
-  }
-}
diff --git a/core/lib/Drupal/Core/Entity/Field/Type/LanguageItem.php b/core/lib/Drupal/Core/Entity/Field/Type/LanguageItem.php
index eb02069..c861f2d 100644
--- a/core/lib/Drupal/Core/Entity/Field/Type/LanguageItem.php
+++ b/core/lib/Drupal/Core/Entity/Field/Type/LanguageItem.php
@@ -51,23 +51,28 @@ public function getPropertyDefinitions() {
    */
   public function setValue($values, $notify = TRUE) {
     // Treat the values as property value of the language property, if no array
-    // is given.
+    // is given as this handles language codes and objects.
     if (isset($values) && !is_array($values)) {
-      $values = array('language' => $values);
+      // Directly update the property instead of invoking the parent, so that
+      // the language property can take care of updating the language code
+      // property.
+      $this->properties['language']->setValue($values, $notify);
     }
-    // Make sure that the 'language' property gets set as 'value'.
-    if (isset($values['value']) && !isset($values['language'])) {
-      $values['language'] = $values['value'];
+    else {
+      // Make sure that the 'language' property gets set as 'value'.
+      if (isset($values['value']) && !isset($values['language'])) {
+        $values['language'] = $values['value'];
+      }
+      parent::setValue($values, $notify);
     }
-    parent::setValue($values, $notify);
   }
 
   /**
-   * Overrides \Drupal\Core\TypedData\TypedDataInterface::applyDefaultValue().
+   * {@inheritdoc}
    */
-  public function applyDefaultValue() {
-    // Default to no default value.
-    $this->setValue(NULL);
+  public function applyDefaultValue($notify = TRUE) {
+    // Default to LANGUAGE_NOT_SPECIFIED.
+    $this->setValue(array('value' => LANGUAGE_NOT_SPECIFIED), $notify);
     return $this;
   }
 }
diff --git a/core/lib/Drupal/Core/Entity/Field/Type/UUIDField.php b/core/lib/Drupal/Core/Entity/Field/Type/UUIDField.php
deleted file mode 100644
index 0bc447a..0000000
--- a/core/lib/Drupal/Core/Entity/Field/Type/UUIDField.php
+++ /dev/null
@@ -1,28 +0,0 @@
-<?php
-
-/**
- * @file
- * Contains \Drupal\Core\Entity\Field\Type\UUIDField.
- */
-
-namespace Drupal\Core\Entity\Field\Type;
-
-use Drupal\Component\Uuid\Uuid;
-
-/**
- * Defines a field class for the 'uuid_field' entity field.
- *
- * The field uses a newly generated UUID as default value.
- */
-class UUIDField extends Field {
-
-  /**
-   * Overrides \Drupal\Core\TypedData\TypedDataInterface::applyDefaultValue().
-   */
-  public function applyDefaultValue() {
-    // Default to one field item with a generated UUID.
-    $uuid = new Uuid();
-    $this->setValue(array(0 => array('value' => $uuid->generate())));
-    return $this;
-  }
-}
diff --git a/core/lib/Drupal/Core/Entity/Field/Type/UuidItem.php b/core/lib/Drupal/Core/Entity/Field/Type/UuidItem.php
new file mode 100644
index 0000000..2384c5f
--- /dev/null
+++ b/core/lib/Drupal/Core/Entity/Field/Type/UuidItem.php
@@ -0,0 +1,28 @@
+<?php
+
+/**
+ * @file
+ * Contains \Drupal\Core\Entity\Field\Type\UuidItem.
+ */
+
+namespace Drupal\Core\Entity\Field\Type;
+
+use Drupal\Component\Uuid\Uuid;
+
+/**
+ * Defines the 'uuid_field' entity field item.
+ *
+ * The field uses a newly generated UUID as default value.
+ */
+class UuidItem extends StringItem {
+
+  /**
+   * Overrides \Drupal\Core\TypedData\TypedDataInterface::applyDefaultValue().
+   */
+  public function applyDefaultValue($notify = TRUE) {
+    // Default to one field item with a generated UUID.
+    $uuid = new Uuid();
+    $this->setValue(array('value' => $uuid->generate()), $notify);
+    return $this;
+  }
+}
diff --git a/core/lib/Drupal/Core/TypedData/ItemList.php b/core/lib/Drupal/Core/TypedData/ItemList.php
index 7f9afdf..88af366 100644
--- a/core/lib/Drupal/Core/TypedData/ItemList.php
+++ b/core/lib/Drupal/Core/TypedData/ItemList.php
@@ -133,14 +133,7 @@ public function offsetGet($offset) {
    * @return \Drupal\Core\TypedData\TypedDataInterface
    */
   protected function createItem($offset = 0, $value = NULL) {
-    $item = typed_data()->getPropertyInstance($this, $offset);
-    if (isset($value)) {
-      $item->setValue($value);
-    }
-    else {
-      $item->applyDefaultValue();
-    }
-    return $item;
+    return typed_data()->getPropertyInstance($this, $offset, $value);
   }
 
   /**
diff --git a/core/lib/Drupal/Core/TypedData/Type/Map.php b/core/lib/Drupal/Core/TypedData/Type/Map.php
index da20e96..4bb802d 100644
--- a/core/lib/Drupal/Core/TypedData/Type/Map.php
+++ b/core/lib/Drupal/Core/TypedData/Type/Map.php
@@ -230,4 +230,14 @@ public function onChange($property_name) {
       $this->parent->onChange($this->name);
     }
   }
+
+  /**
+   * {@inheritdoc}
+   */
+  public function applyDefaultValue($notify = TRUE) {
+    // Apply the default value of all properties.
+    foreach ($this->getProperties() as $property) {
+      $property->applyDefaultValue(FALSE);
+    }
+  }
 }
diff --git a/core/lib/Drupal/Core/TypedData/TypedData.php b/core/lib/Drupal/Core/TypedData/TypedData.php
index 11538fd..073fe17 100644
--- a/core/lib/Drupal/Core/TypedData/TypedData.php
+++ b/core/lib/Drupal/Core/TypedData/TypedData.php
@@ -114,9 +114,9 @@ public function validate() {
   /**
    * Implements \Drupal\Core\TypedData\TypedDataInterface::applyDefaultValue().
    */
-  public function applyDefaultValue() {
+  public function applyDefaultValue($notify = TRUE) {
     // Default to no default value.
-    $this->setValue(NULL);
+    $this->setValue(NULL, $notify);
     return $this;
   }
 
diff --git a/core/lib/Drupal/Core/TypedData/TypedDataInterface.php b/core/lib/Drupal/Core/TypedData/TypedDataInterface.php
index 19febbd..96229b6 100644
--- a/core/lib/Drupal/Core/TypedData/TypedDataInterface.php
+++ b/core/lib/Drupal/Core/TypedData/TypedDataInterface.php
@@ -81,10 +81,15 @@ public function validate();
   /**
    * Applies the default value.
    *
+   * @param bool $notify
+   *   (optional) Whether to notify the parent object of the change. Defaults to
+   *   TRUE. If a property is updated from a parent object, set it to FALSE to
+   *   avoid being notified again.
+   *
    * @return \Drupal\Core\TypedData\TypedDataInterface
    *   Returns itself to allow for chaining.
    */
-  public function applyDefaultValue();
+  public function applyDefaultValue($notify = TRUE);
 
   /**
    * Returns the name of a property or item.
diff --git a/core/modules/file/lib/Drupal/file/Type/FileItem.php b/core/modules/file/lib/Drupal/file/Type/FileItem.php
index 0b2c74b..4a35e9c 100644
--- a/core/modules/file/lib/Drupal/file/Type/FileItem.php
+++ b/core/modules/file/lib/Drupal/file/Type/FileItem.php
@@ -61,15 +61,19 @@ public function getPropertyDefinitions() {
    * Overrides \Drupal\Core\Entity\Field\FieldItemBase::get().
    */
   public function setValue($values, $notify = TRUE) {
-    // Treat the values as property value of the entity property, if no array is
-    // given.
+    // Treat the values as value of the entity property, if no array is
+    // given as this handles entity IDs and objects.
     if (isset($values) && !is_array($values)) {
-      $values = array('entity' => $values);
+      // Directly update the property instead of invoking the parent, so that
+      // the entity property can take care of updating the ID property.
+      $this->properties['entity']->setValue($values, $notify);
     }
-    // Make sure that the 'entity' property gets set as 'fid'.
-    if (isset($values['fid']) && !isset($values['entity'])) {
-      $values['entity'] = $values['fid'];
+    else {
+      // Make sure that the 'entity' property gets set as 'target_id'.
+      if (isset($values['fid']) && !isset($values['entity'])) {
+        $values['entity'] = $values['fid'];
+      }
+      parent::setValue($values, $notify);
     }
-    parent::setValue($values, $notify);
   }
 }
diff --git a/core/modules/image/lib/Drupal/image/Type/ImageItem.php b/core/modules/image/lib/Drupal/image/Type/ImageItem.php
index f6cedf2..868b4fb 100644
--- a/core/modules/image/lib/Drupal/image/Type/ImageItem.php
+++ b/core/modules/image/lib/Drupal/image/Type/ImageItem.php
@@ -68,15 +68,19 @@ public function getPropertyDefinitions() {
    * Overrides \Drupal\Core\Entity\Field\FieldItemBase::get().
    */
   public function setValue($values, $notify = TRUE) {
-    // Treat the values as property value of the entity property, if no array is
-    // given.
+    // Treat the values as value of the entity property, if no array is
+    // given as this handles entity IDs and objects.
     if (isset($values) && !is_array($values)) {
-      $values = array('entity' => $values);
+      // Directly update the property instead of invoking the parent, so that
+      // the entity property can take care of updating the ID property.
+      $this->properties['entity']->setValue($values, $notify);
     }
-    // Make sure that the 'entity' property gets set as 'fid'.
-    if (isset($values['fid']) && !isset($values['entity'])) {
-      $values['entity'] = $values['fid'];
+    else {
+      // Make sure that the 'entity' property gets set as 'target_id'.
+      if (isset($values['fid']) && !isset($values['entity'])) {
+        $values['entity'] = $values['fid'];
+      }
+      parent::setValue($values, $notify);
     }
-    parent::setValue($values, $notify);
   }
 }
diff --git a/core/modules/system/system.module b/core/modules/system/system.module
index b040863..e22c227 100644
--- a/core/modules/system/system.module
+++ b/core/modules/system/system.module
@@ -2361,7 +2361,7 @@ function system_data_type_info() {
       'label' => t('Language field item'),
       'description' => t('An entity field referencing a language.'),
       'class' => '\Drupal\Core\Entity\Field\Type\LanguageItem',
-      'list class' => '\Drupal\Core\Entity\Field\Type\LanguageField',
+      'list class' => '\Drupal\Core\Entity\Field\Type\Field',
     ),
     'entity_reference_field' => array(
       'label' => t('Entity reference field item'),
@@ -2378,8 +2378,8 @@ function system_data_type_info() {
     'uuid_field' => array(
       'label' => t('UUID field item'),
       'description' => t('An entity field containing a UUID.'),
-      'class' => '\Drupal\Core\Entity\Field\Type\StringItem',
-      'list class' => '\Drupal\Core\Entity\Field\Type\UUIDField',
+      'class' => '\Drupal\Core\Entity\Field\Type\UuidItem',
+      'list class' => '\Drupal\Core\Entity\Field\Type\Field',
     ),
   );
 }
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 3aad4a7..af50b25 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
@@ -116,16 +116,6 @@ class Term extends EntityNG implements TermInterface {
   public $parent;
 
   /**
-   * Default values for the term.
-   *
-   * @var array
-   */
-  protected $values = array(
-    'langcode' => array(LANGUAGE_DEFAULT => array(0 => array('value' => LANGUAGE_NOT_SPECIFIED))),
-    'weight' => array(LANGUAGE_DEFAULT => array(0 => array('value' => 0))),
-  );
-
-  /**
    * Implements Drupal\Core\Entity\EntityInterface::id().
    */
   public function id() {
diff --git a/core/modules/taxonomy/lib/Drupal/taxonomy/TermStorageController.php b/core/modules/taxonomy/lib/Drupal/taxonomy/TermStorageController.php
index bea7976..58f6f55 100644
--- a/core/modules/taxonomy/lib/Drupal/taxonomy/TermStorageController.php
+++ b/core/modules/taxonomy/lib/Drupal/taxonomy/TermStorageController.php
@@ -158,11 +158,14 @@ public function baseFieldDefinitions() {
       'label' => t('Weight'),
       'description' => t('The weight of this term in relation to other terms.'),
       'type' => 'integer_field',
+      'settings' => array('default_value' => 0),
     );
     $properties['parent'] = array(
       'label' => t('Term Parents'),
       'description' => t('The parents of this term.'),
       'type' => 'integer_field',
+      // Save new terms with no parents by default.
+      'settings' => array('default_value' => 0),
       'computed' => TRUE,
     );
     return $properties;
diff --git a/core/modules/taxonomy/lib/Drupal/taxonomy/Type/TaxonomyTermReferenceItem.php b/core/modules/taxonomy/lib/Drupal/taxonomy/Type/TaxonomyTermReferenceItem.php
index b558d97..94bb022 100644
--- a/core/modules/taxonomy/lib/Drupal/taxonomy/Type/TaxonomyTermReferenceItem.php
+++ b/core/modules/taxonomy/lib/Drupal/taxonomy/Type/TaxonomyTermReferenceItem.php
@@ -53,15 +53,19 @@ public function getPropertyDefinitions() {
    * Overrides \Drupal\Core\Entity\Field\FieldItemBase::get().
    */
   public function setValue($values, $notify = TRUE) {
-    // Treat the values as property value of the entity property, if no array is
-    // given.
+    // Treat the values as value of the entity property, if no array is
+    // given as this handles entity IDs and objects.
     if (isset($values) && !is_array($values)) {
-      $values = array('entity' => $values);
+      // Directly update the property instead of invoking the parent, so that
+      // the entity property can take care of updating the ID property.
+      $this->properties['entity']->setValue($values, $notify);
     }
-    // Make sure that the 'entity' property gets set as 'tid'.
-    if (isset($values['tid']) && !isset($values['entity'])) {
-      $values['entity'] = $values['tid'];
+    else {
+      // Make sure that the 'entity' property gets set as 'target_id'.
+      if (isset($values['tid']) && !isset($values['entity'])) {
+        $values['entity'] = $values['tid'];
+      }
+      parent::setValue($values, $notify);
     }
-    parent::setValue($values, $notify);
   }
 }
diff --git a/core/modules/text/lib/Drupal/text/Type/TextItem.php b/core/modules/text/lib/Drupal/text/Type/TextItem.php
index fecfaac..848f5ec 100644
--- a/core/modules/text/lib/Drupal/text/Type/TextItem.php
+++ b/core/modules/text/lib/Drupal/text/Type/TextItem.php
@@ -52,12 +52,12 @@ public function getPropertyDefinitions() {
   }
 
   /**
-   * Overrides \Drupal\Core\TypedData\TypedDataInterface::applyDefaultValue().
+   * {@inheritdoc}
    */
-  public function applyDefaultValue() {
+  public function applyDefaultValue($notify = TRUE) {
     // Default to a simple check_plain().
     // @todo: Add in the filter default format here.
-    $this->setValue(array('format' => NULL));
+    $this->setValue(array('format' => NULL), $notify);
     return $this;
   }