diff --git a/AsyncDisplayKit/ASDisplayNode.h b/AsyncDisplayKit/ASDisplayNode.h
index 3d84ee9290..83ff98bc26 100644
--- a/AsyncDisplayKit/ASDisplayNode.h
+++ b/AsyncDisplayKit/ASDisplayNode.h
@@ -351,7 +351,7 @@ NS_ASSUME_NONNULL_BEGIN
 /** 
  * @abstract The receiver's immediate subnodes.
  */
-@property (nonatomic, readonly, strong) NSArray<ASDisplayNode *> *subnodes;
+@property (nonatomic, readonly, copy) NSArray<ASDisplayNode *> *subnodes;
 
 /** 
  * @abstract The receiver's supernode.
diff --git a/AsyncDisplayKit/ASDisplayNodeExtras.mm b/AsyncDisplayKit/ASDisplayNodeExtras.mm
index 2b384bbdac..dad6da1b70 100644
--- a/AsyncDisplayKit/ASDisplayNodeExtras.mm
+++ b/AsyncDisplayKit/ASDisplayNodeExtras.mm
@@ -51,7 +51,9 @@ extern void ASDisplayNodePerformBlockOnEveryNode(CALayer *layer, ASDisplayNode *
   }
   
   if (layer) {
-    for (CALayer *sublayer in [layer sublayers]) {
+    /// NOTE: The docs say `sublayers` returns a copy, but it does not.
+    /// See: http://stackoverflow.com/questions/14854480/collection-calayerarray-0x1ed8faa0-was-mutated-while-being-enumerated
+    for (CALayer *sublayer in [[layer sublayers] copy]) {
       ASDisplayNodePerformBlockOnEveryNode(sublayer, nil, block);
     }
   } else if (node) {