It's better with LINQ
Create your nodes to a list collection List<radTreeNode>
Sort the List, then add to the nodes using the AddRange method.
Here's the sort in LINQ.
protected List<RadTreeNode> SortNodeCollection(List<RadTreeNode> nodes)
{
List<RadTreeNode> returnCollection = new List<RadTreeNode>();
var q = from node in nodes
orderby node.Text ascending
select node;
returnCollection = q.ToList<
RadTreeNode>();
return returnCollection;
}