I am writing my own plugin and have a problem with the tree nodes rendering when moving away and back again to the page. Basically the node text keeps adding on each refresh of the page.

The code is:

namespace UmbRecruit
{
    public class loadRecruit : BaseTree
    {

        public loadRecruit(string application)
            : base(application)
        { }

        protected override void CreateRootNode(ref XmlTreeNode rootNode)
        {
            rootNode.Icon = FolderIcon;
            rootNode.OpenIcon = FolderIconOpen;
            rootNode.NodeType = "init" + TreeAlias;
            rootNode.Action = "javascript:openCreateJob()";
            rootNode.NodeID = "init";
        }


        public override void Render(ref XmlTree Tree)
        {


            var CreateJob = XmlTreeNode.Create(this);
            CreateJob.Text = "Create New Job";
            CreateJob.Icon = "new.png";
            CreateJob.Action = "javascript:openCreateJob()";
            Tree.Add(CreateJob);

            var ViewJobs = XmlTreeNode.Create(this);
            ViewJobs.Text = "View Current Vacancies";
            ViewJobs.Icon = "table.png";
            ViewJobs.Action = "javascript.openViewJobs()";
            Tree.Add(ViewJobs);
    
        }

        public override void RenderJS(ref StringBuilder Javascript)
        {
            Javascript.Append(@"
                function openCreateJob(){
                    parent.right.document.location.href='plugins/Recruitment/CreateNewJob.aspx';
                   }
                   function openViewJobs(){
                    parent.right.document.location.href='plugins/Recruitment/ViewVacancies.aspx';
                    }
               ");

        }
    }
}

Anybody got any ideas what I am doing wrong?