diff --git a/core/modules/field/field.install b/core/modules/field/field.install
index 16b09e1..8aba2da 100644
--- a/core/modules/field/field.install
+++ b/core/modules/field/field.install
@@ -103,10 +103,9 @@ function field_schema() {
       'active' => array('active'),
       'storage_active' => array('storage_active'),
       'deleted' => array('deleted'),
-      // Used by field_modules_disabled().
+      // Used by field_sync_field_status().
       'module' => array('module'),
       'storage_module' => array('storage_module'),
-      // Used by field_associate_fields().
       'type' => array('type'),
       'storage_type' => array('storage_type'),
     ),
diff --git a/core/modules/field/field.module b/core/modules/field/field.module
index 9129fd5..d1e4f73 100644
--- a/core/modules/field/field.module
+++ b/core/modules/field/field.module
@@ -362,11 +362,12 @@ function field_theme() {
 
 /**
  * Implements hook_cron().
- *
- * Purges some deleted Field API data, if any exists.
  */
 function field_cron() {
+  // Refresh the 'active' status of fields.
   field_sync_field_status();
+
+  // Do a pass of purging on deleted Field API data, if any exists.
   $limit = variable_get('field_purge_batch_size', 10);
   field_purge_batch($limit);
 }
@@ -412,11 +413,30 @@ function field_system_info_alter(&$info, $file, $type) {
  * Implements hook_flush_caches().
  */
 function field_flush_caches() {
+  // Refresh the 'active' status of fields.
   field_sync_field_status();
+
+ // Request a flush of our cache table.
   return array('field');
 }
 
 /**
+ * Implements hook_modules_enabled().
+ */
+function field_modules_enabled($modules) {
+  // Refresh the 'active' status of fields.
+  field_sync_field_status();
+}
+
+/**
+ * Implements hook_modules_disabled().
+ */
+function field_modules_disabled($modules) {
+  // Refresh the 'active' status of fields.
+  field_sync_field_status();
+}
+
+/**
  * Refreshes the 'active' and 'storage_active' columns for fields.
  */
 function field_sync_field_status() {
@@ -449,18 +469,18 @@ function field_sync_field_status() {
 function field_associate_fields($module) {
   // Associate field types.
   $field_types = (array) module_invoke($module, 'field_info');
-  foreach ($field_types as $name => $field_info) {
+  if ($field_types) {
     db_update('field_config')
       ->fields(array('module' => $module, 'active' => 1))
-      ->condition('type', $name)
+      ->condition('type', array_keys($field_types))
       ->execute();
   }
   // Associate storage backends.
   $storage_types = (array) module_invoke($module, 'field_storage_info');
-  foreach ($storage_types as $name => $storage_info) {
+  if ($storage_types) {
     db_update('field_config')
       ->fields(array('storage_module' => $module, 'storage_active' => 1))
-      ->condition('storage_type', $name)
+      ->condition('storage_type', array_keys($storage_types))
       ->execute();
   }
 }
diff --git a/core/modules/field/tests/field.test b/core/modules/field/tests/field.test
index 0733bd0..bb3206a 100644
--- a/core/modules/field/tests/field.test
+++ b/core/modules/field/tests/field.test
@@ -2357,7 +2357,6 @@ class FieldCrudTestCase extends FieldTestCase {
     $this->assertTrue($field_definition <= $field, t('The field was properly read.'));
 
     module_disable($modules, FALSE);
-    drupal_flush_all_caches();
 
     $fields = field_read_fields(array('field_name' => $field_name), array('include_inactive' => TRUE));
     $this->assertTrue(isset($fields[$field_name]) && $field_definition < $field, t('The field is properly read when explicitly fetching inactive fields.'));
@@ -2370,7 +2369,6 @@ class FieldCrudTestCase extends FieldTestCase {
 
       $module = array_shift($modules);
       module_enable(array($module), FALSE);
-      drupal_flush_all_caches();
     }
 
     // Check that the field is active again after all modules have been
diff --git a/core/modules/taxonomy/taxonomy.test b/core/modules/taxonomy/taxonomy.test
index a7f7bd9..d58eb7b 100644
--- a/core/modules/taxonomy/taxonomy.test
+++ b/core/modules/taxonomy/taxonomy.test
@@ -375,7 +375,6 @@ class TaxonomyVocabularyUnitTest extends TaxonomyWebTestCase {
     field_create_instance($this->instance);
 
     module_disable(array('taxonomy'));
-    drupal_flush_all_caches();
     require_once DRUPAL_ROOT . '/core/includes/install.inc';
     drupal_uninstall_modules(array('taxonomy'));
     module_enable(array('taxonomy'));