diff --git a/trie/fullnode.go b/trie/fullnode.go
index 522fdb373..95c8eb4be 100644
--- a/trie/fullnode.go
+++ b/trie/fullnode.go
@@ -1,17 +1,16 @@
 package trie
 
-import "fmt"
-
 type FullNode struct {
 	trie  *Trie
 	nodes [17]Node
+	dirty bool
 }
 
 func NewFullNode(t *Trie) *FullNode {
 	return &FullNode{trie: t}
 }
 
-func (self *FullNode) Dirty() bool { return true }
+func (self *FullNode) Dirty() bool { return self.dirty }
 func (self *FullNode) Value() Node {
 	self.nodes[16] = self.trie.trans(self.nodes[16])
 	return self.nodes[16]
@@ -27,6 +26,7 @@ func (self *FullNode) Copy(t *Trie) Node {
 			nnode.nodes[i] = node.Copy(t)
 		}
 	}
+	nnode.dirty = true
 
 	return nnode
 }
@@ -60,11 +60,8 @@ func (self *FullNode) RlpData() interface{} {
 }
 
 func (self *FullNode) set(k byte, value Node) {
-	if _, ok := value.(*ValueNode); ok && k != 16 {
-		fmt.Println(value, k)
-	}
-
 	self.nodes[int(k)] = value
+	self.dirty = true
 }
 
 func (self *FullNode) branch(i byte) Node {
@@ -75,3 +72,7 @@ func (self *FullNode) branch(i byte) Node {
 	}
 	return nil
 }
+
+func (self *FullNode) setDirty(dirty bool) {
+	self.dirty = dirty
+}
diff --git a/trie/hashnode.go b/trie/hashnode.go
index 8125cc3c9..e82ab8069 100644
--- a/trie/hashnode.go
+++ b/trie/hashnode.go
@@ -3,12 +3,13 @@ package trie
 import "github.com/ethereum/go-ethereum/common"
 
 type HashNode struct {
-	key  []byte
-	trie *Trie
+	key   []byte
+	trie  *Trie
+	dirty bool
 }
 
 func NewHash(key []byte, trie *Trie) *HashNode {
-	return &HashNode{key, trie}
+	return &HashNode{key, trie, false}
 }
 
 func (self *HashNode) RlpData() interface{} {
@@ -19,6 +20,10 @@ func (self *HashNode) Hash() interface{} {
 	return self.key
 }
 
+func (self *HashNode) setDirty(dirty bool) {
+	self.dirty = dirty
+}
+
 // These methods will never be called but we have to satisfy Node interface
 func (self *HashNode) Value() Node       { return nil }
 func (self *HashNode) Dirty() bool       { return true }
diff --git a/trie/node.go b/trie/node.go
index 0d8a7cff9..dccbc64a3 100644
--- a/trie/node.go
+++ b/trie/node.go
@@ -11,6 +11,7 @@ type Node interface {
 	fstring(string) string
 	Hash() interface{}
 	RlpData() interface{}
+	setDirty(dirty bool)
 }
 
 // Value node
diff --git a/trie/shortnode.go b/trie/shortnode.go
index edd490b4d..c86e50096 100644
--- a/trie/shortnode.go
+++ b/trie/shortnode.go
@@ -6,20 +6,22 @@ type ShortNode struct {
 	trie  *Trie
 	key   []byte
 	value Node
+	dirty bool
 }
 
 func NewShortNode(t *Trie, key []byte, value Node) *ShortNode {
-	return &ShortNode{t, []byte(CompactEncode(key)), value}
+	return &ShortNode{t, []byte(CompactEncode(key)), value, false}
 }
 func (self *ShortNode) Value() Node {
 	self.value = self.trie.trans(self.value)
 
 	return self.value
 }
-func (self *ShortNode) Dirty() bool { return true }
+func (self *ShortNode) Dirty() bool { return self.dirty }
 func (self *ShortNode) Copy(t *Trie) Node {
-	node := &ShortNode{t, nil, self.value.Copy(t)}
+	node := &ShortNode{t, nil, self.value.Copy(t), self.dirty}
 	node.key = common.CopyBytes(self.key)
+	node.dirty = true
 	return node
 }
 
@@ -33,3 +35,7 @@ func (self *ShortNode) Hash() interface{} {
 func (self *ShortNode) Key() []byte {
 	return CompactDecode(string(self.key))
 }
+
+func (self *ShortNode) setDirty(dirty bool) {
+	self.dirty = dirty
+}
diff --git a/trie/trie.go b/trie/trie.go
index d990338ee..7e17baa2f 100644
--- a/trie/trie.go
+++ b/trie/trie.go
@@ -117,7 +117,9 @@ func (self *Trie) Update(key, value []byte) Node {
 	k := CompactHexDecode(string(key))
 
 	if len(value) != 0 {
-		self.root = self.insert(self.root, k, &ValueNode{self, value})
+		node := NewValueNode(self, value)
+		node.dirty = true
+		self.root = self.insert(self.root, k, node)
 	} else {
 		self.root = self.delete(self.root, k)
 	}
@@ -157,7 +159,9 @@ func (self *Trie) insert(node Node, key []byte, value Node) Node {
 	}
 
 	if node == nil {
-		return NewShortNode(self, key, value)
+		node := NewShortNode(self, key, value)
+		node.dirty = true
+		return node
 	}
 
 	switch node := node.(type) {
@@ -165,7 +169,10 @@ func (self *Trie) insert(node Node, key []byte, value Node) Node {
 		k := node.Key()
 		cnode := node.Value()
 		if bytes.Equal(k, key) {
-			return NewShortNode(self, key, value)
+			node := NewShortNode(self, key, value)
+			node.dirty = true
+			return node
+
 		}
 
 		var n Node
@@ -176,6 +183,7 @@ func (self *Trie) insert(node Node, key []byte, value Node) Node {
 			pnode := self.insert(nil, k[matchlength+1:], cnode)
 			nnode := self.insert(nil, key[matchlength+1:], value)
 			fulln := NewFullNode(self)
+			fulln.dirty = true
 			fulln.set(k[matchlength], pnode)
 			fulln.set(key[matchlength], nnode)
 			n = fulln
@@ -184,11 +192,14 @@ func (self *Trie) insert(node Node, key []byte, value Node) Node {
 			return n
 		}
 
-		return NewShortNode(self, key[:matchlength], n)
+		snode := NewShortNode(self, key[:matchlength], n)
+		snode.dirty = true
+		return snode
 
 	case *FullNode:
 		cpy := node.Copy(self).(*FullNode)
 		cpy.set(key[0], self.insert(node.branch(key[0]), key[1:], value))
+		cpy.dirty = true
 
 		return cpy
 
@@ -242,8 +253,10 @@ func (self *Trie) delete(node Node, key []byte) Node {
 			case *ShortNode:
 				nkey := append(k, child.Key()...)
 				n = NewShortNode(self, nkey, child.Value())
+				n.(*ShortNode).dirty = true
 			case *FullNode:
 				sn := NewShortNode(self, node.Key(), child)
+				sn.dirty = true
 				sn.key = node.key
 				n = sn
 			}
@@ -256,6 +269,7 @@ func (self *Trie) delete(node Node, key []byte) Node {
 	case *FullNode:
 		n := node.Copy(self).(*FullNode)
 		n.set(key[0], self.delete(n.branch(key[0]), key[1:]))
+		n.dirty = true
 
 		pos := -1
 		for i := 0; i < 17; i++ {
@@ -271,6 +285,7 @@ func (self *Trie) delete(node Node, key []byte) Node {
 		var nnode Node
 		if pos == 16 {
 			nnode = NewShortNode(self, []byte{16}, n.branch(byte(pos)))
+			nnode.(*ShortNode).dirty = true
 		} else if pos >= 0 {
 			cnode := n.branch(byte(pos))
 			switch cnode := cnode.(type) {
@@ -278,8 +293,10 @@ func (self *Trie) delete(node Node, key []byte) Node {
 				// Stitch keys
 				k := append([]byte{byte(pos)}, cnode.Key()...)
 				nnode = NewShortNode(self, k, cnode.Value())
+				nnode.(*ShortNode).dirty = true
 			case *FullNode:
 				nnode = NewShortNode(self, []byte{byte(pos)}, n.branch(byte(pos)))
+				nnode.(*ShortNode).dirty = true
 			}
 		} else {
 			nnode = n
@@ -304,7 +321,7 @@ func (self *Trie) mknode(value *common.Value) Node {
 		if value.Get(0).Len() != 0 {
 			key := CompactDecode(string(value.Get(0).Bytes()))
 			if key[len(key)-1] == 16 {
-				return NewShortNode(self, key, &ValueNode{self, value.Get(1).Bytes()})
+				return NewShortNode(self, key, NewValueNode(self, value.Get(1).Bytes()))
 			} else {
 				return NewShortNode(self, key, self.mknode(value.Get(1)))
 			}
@@ -318,10 +335,10 @@ func (self *Trie) mknode(value *common.Value) Node {
 			return fnode
 		}
 	case 32:
-		return &HashNode{value.Bytes(), self}
+		return NewHash(value.Bytes(), self)
 	}
 
-	return &ValueNode{self, value.Bytes()}
+	return NewValueNode(self, value.Bytes())
 }
 
 func (self *Trie) trans(node Node) Node {
@@ -338,7 +355,11 @@ func (self *Trie) store(node Node) interface{} {
 	data := common.Encode(node)
 	if len(data) >= 32 {
 		key := crypto.Sha3(data)
-		self.cache.Put(key, data)
+		if node.Dirty() {
+			//fmt.Println("save", node)
+			//fmt.Println()
+			self.cache.Put(key, data)
+		}
 
 		return key
 	}
diff --git a/trie/trie_test.go b/trie/trie_test.go
index 9a58958d8..60f0873a8 100644
--- a/trie/trie_test.go
+++ b/trie/trie_test.go
@@ -152,7 +152,7 @@ func TestReplication(t *testing.T) {
 	}
 	trie.Commit()
 
-	trie2 := New(trie.roothash, trie.cache.backend)
+	trie2 := New(trie.Root(), trie.cache.backend)
 	if string(trie2.GetString("horse")) != "stallion" {
 		t.Error("expected to have horse => stallion")
 	}
diff --git a/trie/valuenode.go b/trie/valuenode.go
index 7bf8ff06e..6adb59652 100644
--- a/trie/valuenode.go
+++ b/trie/valuenode.go
@@ -3,13 +3,24 @@ package trie
 import "github.com/ethereum/go-ethereum/common"
 
 type ValueNode struct {
-	trie *Trie
-	data []byte
+	trie  *Trie
+	data  []byte
+	dirty bool
 }
 
-func (self *ValueNode) Value() Node          { return self } // Best not to call :-)
-func (self *ValueNode) Val() []byte          { return self.data }
-func (self *ValueNode) Dirty() bool          { return true }
-func (self *ValueNode) Copy(t *Trie) Node    { return &ValueNode{t, common.CopyBytes(self.data)} }
+func NewValueNode(trie *Trie, data []byte) *ValueNode {
+	return &ValueNode{trie, data, false}
+}
+
+func (self *ValueNode) Value() Node { return self } // Best not to call :-)
+func (self *ValueNode) Val() []byte { return self.data }
+func (self *ValueNode) Dirty() bool { return self.dirty }
+func (self *ValueNode) Copy(t *Trie) Node {
+	return &ValueNode{t, common.CopyBytes(self.data), self.dirty}
+}
 func (self *ValueNode) RlpData() interface{} { return self.data }
 func (self *ValueNode) Hash() interface{}    { return self.data }
+
+func (self *ValueNode) setDirty(dirty bool) {
+	self.dirty = dirty
+}