Public Sub CopyNode(node As TreeNode, dest As TreeNodeCollection)
	Dim copy As New TreeNode(node.Name) '= CType(node.Clone(), TreeNode)
	copy.Text=node.Text
	
    dest.Add(copy)
    
    For Each child As TreeNode In node.Nodes
        CopyNode(child, copy.Nodes)
    Next
    
End Sub

Public Sub CopyTree(src As TreeView, dest As TreeView)
    For Each node As TreeNode In src.Nodes
        CopyNode(node, dest.Nodes)
    Next
End Sub

Public Class MainForm

Sub Button1_Click(sender As Object, e As EventArgs)
    TreeViewClone(treeView1, treeView2)		
    treeView2.ExpandAll()
End Sub

Public Sub TreeViewClone(FromTV As TreeView, ToTV As TreeView)
    For Each xNode As TreeNode In FromTV.Nodes
        Dim copyNodes As TreeNode = CType(xNode.Clone(), TreeNode)
        ToTV.Nodes.Add(copyNodes)
    Next
End Sub

Sub MainForm_Load(sender As Object, e As EventArgs)
    treeView1.Nodes.AddRange(New TreeNode() { New TreeNode("Уровень 1.1"), New TreeNode("Уровень 1.2"), New TreeNode("Уровень 1.3") })
    treeView1.Nodes(0).Nodes.AddRange(New TreeNode() { New TreeNode("Уровень 1.1.1"), New TreeNode("Уровень 1.1.2")})
    treeView1.Nodes(1).Nodes.AddRange(New TreeNode() { New TreeNode("Уровень 1.2.1"), New TreeNode("Уровень 1.2.2"), New TreeNode("Уровень 1.2.3")})
    treeView1.Nodes(2).Nodes.AddRange(New TreeNode() { New TreeNode("Уровень 1.3.1"), New TreeNode("Уровень 1.3.2"), New TreeNode("Уровень 1.3.3")})
    treeView1.Nodes(0).Nodes(0).Nodes.AddRange(New TreeNode() { New TreeNode("Уровень 1.1.1.1"), New TreeNode("Уровень 1.1.1.2")})
    treeView1.Nodes(0).Nodes(1).Nodes.AddRange(New TreeNode() { New TreeNode("Уровень 1.1.2.1"), New TreeNode("Уровень 1.1.2.2")})
    treeView1.Nodes(0).Nodes(1).Nodes(0).Nodes.AddRange(New TreeNode() { New TreeNode("Уровень 1.1.2.1.1")})
    treeView1.ExpandAll()
End Sub
	
End Class