diff --git a/include/osgTerrain/GeometryTechnique b/include/osgTerrain/GeometryTechnique
index 678785fd4..f401a7099 100644
--- a/include/osgTerrain/GeometryTechnique
+++ b/include/osgTerrain/GeometryTechnique
@@ -37,6 +37,9 @@ class OSGTERRAIN_EXPORT GeometryTechnique : public TerrainTechnique
 
         virtual void cull(osgUtil::CullVisitor* nv);
 
+        /** Traverse the terain subgraph.*/
+        virtual void traverse(osg::NodeVisitor& nv);
+
         virtual void cleanSceneGraph();
 
         virtual void dirty();
diff --git a/src/osgTerrain/GeometryTechnique.cpp b/src/osgTerrain/GeometryTechnique.cpp
index 15032041c..5495a1da5 100644
--- a/src/osgTerrain/GeometryTechnique.cpp
+++ b/src/osgTerrain/GeometryTechnique.cpp
@@ -552,6 +552,42 @@ void GeometryTechnique::cull(osgUtil::CullVisitor* cv)
 #endif    
 }
 
+
+void GeometryTechnique::traverse(osg::NodeVisitor& nv)
+{
+    if (!_terrainNode) return;
+
+    // if app traversal update the frame count.
+    if (nv.getVisitorType()==osg::NodeVisitor::UPDATE_VISITOR)
+    {
+        if (_dirty) init();
+
+        osgUtil::UpdateVisitor* uv = dynamic_cast<osgUtil::UpdateVisitor*>(&nv);
+        if (uv)
+        {
+            update(uv);
+            return;
+        }        
+        
+    }
+    else if (nv.getVisitorType()==osg::NodeVisitor::CULL_VISITOR)
+    {
+        osgUtil::CullVisitor* cv = dynamic_cast<osgUtil::CullVisitor*>(&nv);
+        if (cv)
+        {
+            cull(cv);
+            return;
+        }
+    }
+
+
+    if (_dirty) init();
+
+    BufferData& buffer = getReadOnlyBuffer();
+    if (buffer._transform.valid()) buffer._transform->accept(nv);
+}
+
+
 void GeometryTechnique::cleanSceneGraph()
 {
 }
diff --git a/src/osgTerrain/TerrainTechnique.cpp b/src/osgTerrain/TerrainTechnique.cpp
index 8c0536222..ee90614b9 100644
--- a/src/osgTerrain/TerrainTechnique.cpp
+++ b/src/osgTerrain/TerrainTechnique.cpp
@@ -90,6 +90,8 @@ void TerrainTechnique::traverse(osg::NodeVisitor& nv)
         }
     }
 
+    if (_dirty) init();
+
     // otherwise fallback to the Group::traverse()
     _terrainNode->osg::Group::traverse(nv);
 }