diff --git a/src/lib/dom-api.html b/src/lib/dom-api.html
index b18e69607c..929c1ac912 100644
--- a/src/lib/dom-api.html
+++ b/src/lib/dom-api.html
@@ -65,11 +65,15 @@
       // 3. node is <content> (host of container needs distribution)
       appendChild: function(node) {
         var handled;
+        // if a <content> is added, make sure it's parent has logical info.
+        this._ensureContentLogicalInfo(node);
         this._removeNodeFromHost(node, true);
         if (this._nodeIsInLogicalTree(this.node)) {
           this._addLogicalInfo(node, this.node);
           this._addNodeToHost(node);
           handled = this._maybeDistribute(node, this.node);
+        } else {
+          this._addNodeToHost(node);
         }
         // if not distributing and not adding to host, do a fast path addition
         if (!handled && !this._tryRemoveUndistributedNode(node)) {
@@ -86,9 +90,10 @@
           return this.appendChild(node);
         }
         var handled;
+        // if a <content> is added, make sure it's parent has logical info.
+        this._ensureContentLogicalInfo(node);
         this._removeNodeFromHost(node, true);
         if (this._nodeIsInLogicalTree(this.node)) {
-          saveLightChildrenIfNeeded(this.node);
           var children = this.childNodes;
           var index = children.indexOf(ref_node);
           if (index < 0) {
@@ -98,6 +103,8 @@
           this._addLogicalInfo(node, this.node, index);
           this._addNodeToHost(node);
           handled = this._maybeDistribute(node, this.node);
+        } else {
+          this._addNodeToHost(node);
         }
         // if not distributing and not adding to host, do a fast path addition
         if (!handled && !this._tryRemoveUndistributedNode(node)) {
@@ -125,6 +132,8 @@
         if (this._nodeIsInLogicalTree(this.node)) {
           this._removeNodeFromHost(node);
           handled = this._maybeDistribute(node, this.node);
+        } else {
+          this._removeNodeFromHost(node);
         }
         if (!handled) {
           // if removing from a shadyRoot, remove form host instead
@@ -223,18 +232,37 @@
       },
 
       _updateInsertionPoints: function(host) {
-        host.shadyRoot._insertionPoints =
+        var i$ = host.shadyRoot._insertionPoints =
           factory(host.shadyRoot).querySelectorAll(CONTENT);
+        // ensure <content>'s and their parents have logical dom info.
+        for (var i=0, c; i < i$.length; i++) {
+          c = i$[i];
+          saveLightChildrenIfNeeded(c);
+          saveLightChildrenIfNeeded(factory(c).parentNode);
+        }
       },
 
       // a node is in a shadyRoot, is a shadyRoot,
       // or has a lightParent
       _nodeIsInLogicalTree: function(node) {
         return Boolean((node._lightParent !== undefined) || node._isShadyRoot ||
-          this._ownerShadyRootForNode(node) ||
           node.shadyRoot);
       },
 
+      _ensureContentLogicalInfo: function(node) {
+        if (node.nodeType === Node.DOCUMENT_FRAGMENT_NODE) {
+          saveLightChildrenIfNeeded(this.node);
+          var c$ = Array.prototype.slice.call(node.childNodes);
+          for (var i=0, n; (i<c$.length) && (n=c$[i]); i++) {
+            this._ensureContentLogicalInfo(n);
+          }
+        } else if (node.localName === CONTENT) {
+          // should be parent not this.node, but this is before parent is set.
+          saveLightChildrenIfNeeded(this.node);
+          saveLightChildrenIfNeeded(node);
+        }
+      },
+
       _parentNeedsDistribution: function(parent) {
         return parent && parent.shadyRoot && hasInsertionPoint(parent.shadyRoot);
       },
@@ -292,17 +320,15 @@
         }
       },
 
+      // a node being added is always in this same host as this.node.
       _addNodeToHost: function(node) {
-        var checkNode = node.nodeType === Node.DOCUMENT_FRAGMENT_NODE ?
-          node.firstChild : node;
-        var root = this._ownerShadyRootForNode(checkNode);
+        var root = this.getOwnerRoot();
         if (root) {
           root.host._elementAdd(node);
         }
       },
 
       _addLogicalInfo: function(node, container, index) {
-        saveLightChildrenIfNeeded(container);
         var children = factory(container).childNodes;
         index = index === undefined ? children.length : index;
         // handle document fragments
diff --git a/src/mini/shady.html b/src/mini/shady.html
index 8d96fc7b57..cfa5f938cc 100644
--- a/src/mini/shady.html
+++ b/src/mini/shady.html
@@ -53,11 +53,19 @@
         this.shadyRoot._isShadyRoot = true;
         this.shadyRoot._dirtyRoots = [];
         // capture insertion point list
-        this.shadyRoot._insertionPoints = !this._notes || 
+        var i$ = this.shadyRoot._insertionPoints = !this._notes || 
           this._notes._hasContent ?
           this.shadyRoot.querySelectorAll('content') : [];
-        // save logical tree info for shadyRoot.
+        // save logical tree info
+        // a. for shadyRoot 
+        // b. for insertion points (fallback) 
+        // c. for parents of insertion points
         saveLightChildrenIfNeeded(this.shadyRoot);
+        for (var i=0, c; i < i$.length; i++) {
+          c = i$[i];
+          saveLightChildrenIfNeeded(c);
+          saveLightChildrenIfNeeded(c.parentNode);
+        }
         this.shadyRoot.host = this;
       },
 
@@ -406,9 +414,6 @@
       }
       // remove child from its old parent first
       remove(newChild);
-      // make sure we never lose logical DOM information:
-      // if the parentNode doesn't have lightChildren, save that information now.
-      saveLightChildrenIfNeeded(parentNode);
       // insert it into the real DOM
       nativeInsertBefore.call(parentNode, newChild, refChild || null);
       newChild._composedParent = parentNode;
@@ -417,9 +422,6 @@
     function remove(node) {
       var parentNode = getComposedParent(node);
       if (parentNode) {
-        // make sure we never lose logical DOM information:
-        // if the parentNode doesn't have lightChildren, save that information now.
-        saveLightChildrenIfNeeded(parentNode);
         node._composedParent = null;
         // remove it from the real DOM
         nativeRemoveChild.call(parentNode, node);
diff --git a/test/unit/polymer-dom-shadow.html b/test/unit/polymer-dom-shadow.html
index 11f78de268..8e704b3ac0 100644
--- a/test/unit/polymer-dom-shadow.html
+++ b/test/unit/polymer-dom-shadow.html
@@ -47,6 +47,12 @@
 
 <x-redistribute-a-b></x-redistribute-a-b>
 
+<div id="container">
+  <x-echo></x-echo>
+  <span>1</span>
+  <span>2</span>
+</div>
+
 <script src="polymer-dom.js"></script>
 
 </body>
diff --git a/test/unit/polymer-dom.html b/test/unit/polymer-dom.html
index 6b8240d4ff..16671e5a7d 100644
--- a/test/unit/polymer-dom.html
+++ b/test/unit/polymer-dom.html
@@ -47,6 +47,12 @@
 
 <x-redistribute-a-b></x-redistribute-a-b>
 
+<div id="container">
+  <x-echo></x-echo>
+  <span>1</span>
+  <span>2</span>
+</div>
+
 <script src="polymer-dom.js"></script>
 
 </body>
diff --git a/test/unit/polymer-dom.js b/test/unit/polymer-dom.js
index 5ba436b50d..9d26612fa9 100644
--- a/test/unit/polymer-dom.js
+++ b/test/unit/polymer-dom.js
@@ -424,6 +424,34 @@ suite('Polymer.dom', function() {
     assert.equal(Polymer.dom(rere.root).querySelectorAll('span').length, 0);
   });
 
+  test('appendChild interacts with unmanaged parent tree', function() {
+    var container = document.querySelector('#container');
+    var echo = Polymer.dom(container).firstElementChild;
+    assert.equal(echo.localName, 'x-echo');
+    var s1 = Polymer.dom(echo).nextElementSibling;
+    assert.equal(s1.textContent, '1');
+    var s2 = Polymer.dom(s1).nextElementSibling;
+    assert.equal(s2.textContent, '2');
+    assert.equal(Polymer.dom(container).children.length, 3);
+    Polymer.dom(echo).appendChild(s1);
+    Polymer.dom.flush();
+    assert.equal(Polymer.dom(container).children.length, 2);
+    assert.equal(Polymer.dom(echo).nextElementSibling, s2);
+    Polymer.dom(echo).appendChild(s2);
+    Polymer.dom.flush();
+    assert.equal(Polymer.dom(container).children.length, 1);
+    assert.equal(Polymer.dom(echo).nextElementSibling, null);
+    Polymer.dom(container).appendChild(s1);
+    Polymer.dom.flush();
+    assert.equal(Polymer.dom(container).children.length, 2);
+    assert.equal(Polymer.dom(echo).nextElementSibling, s1);
+    Polymer.dom(container).appendChild(s2);
+    Polymer.dom.flush();
+    assert.equal(Polymer.dom(container).children.length, 3);
+    assert.equal(Polymer.dom(echo).nextElementSibling, s1);
+    assert.equal(Polymer.dom(s1).nextElementSibling, s2);
+  });
+
   test('distribute (forced)', function() {
     var rere = Polymer.dom(testElement.root).querySelector('x-rereproject');
     var re = Polymer.dom(rere.root).querySelector('x-reproject');
diff --git a/test/unit/shady.html b/test/unit/shady.html
index 9b3538f1f4..7bd9f45118 100644
--- a/test/unit/shady.html
+++ b/test/unit/shady.html
@@ -473,7 +473,7 @@
 }
 
 function updateRootInsertionPoints(root) {
-  root._insertionPoints = root.querySelectorAll('content');
+  Polymer.dom(root.host)._updateInsertionPoints(root.host);
 }
 
 function getComposedHTML(node) {