Removing Nodes from treeview

Hi guys,

I have come to a little problem with my program. I am displaying files from 'Application.StartupPath' but I trying to get rid of the ParentNode which is the "Debug" folder.

I've got this so far, but no joy:


//Search
        private void button10_Click(object sender, EventArgs e)
        {
            ListDirectorySearch(treeView1, Application.StartupPath);


//Search dir and populate

        public TreeNode CreateDirectoryNodeSearch(DirectoryInfo directoryInfo)
        {
            var directoryNode = new TreeNode(directoryInfo.Name);
            foreach (var directory in directoryInfo.GetDirectories())
                if (directoryInfo.Name == "Debug")
                {
                    treeView1.Nodes.Remove(directoryNode);
                }
                else
                {
                    directoryNode.Nodes.Add(CreateDirectoryNodeSearch(directory));
                }


            foreach (var file in directoryInfo.GetFiles("*" + textBox1.Text + "*.PDF").
                Union(directoryInfo.GetFiles("*.WMV").Union(directoryInfo.GetFiles("*.Mov"))))
                directoryNode.Nodes.Add(new TreeNode(file.Name));
           
                if (directoryNode.Nodes.Count == 0)
                {

                    directoryNode.Nodes.Add("Sorry, No Books Here");
                }

          
            return directoryNode;
        }

 private void ListDirectorySearch(TreeView treeView, string path)
        {
            treeView.Nodes.Clear();
            var rootDirectoryInfo = new DirectoryInfo(path);
            treeView.Nodes.Add(CreateDirectoryNodeSearch(rootDirectoryInfo));
 
        }


so to clarify, my result are:

Debug    <----  (this is what I want to get rid of)
 - folder1
        - file1
        - file2
 - folder2
       - newfile1

Thanks All