Get Specific Folder using SP WebServcie and CAML Query

StringBuilder sbQuery = new StringBuilder(100);
sbQuery.Append("");
sbQuery.Append("<where> ");
sbQuery.Append(" <and>");
sbQuery.Append("<eq> ");
sbQuery.Append("<fieldref name="\">");
sbQuery.Append("<value type="\">1</value>");
sbQuery.Append("</eq>");
sbQuery.Append("<contains>");
sbQuery.Append("<fieldref name="\">");
sbQuery.Append(string.Format("<value type="\">{0}</value>", folderName));
sbQuery.Append("</contains>");
sbQuery.Append(" </and>");
sbQuery.Append("</where>>");
sbQuery.Append("</query>");
sbQuery.Append("<viewfields>");
sbQuery.Append("<fieldref name="\"><fieldref name="\"><fieldref name="\">");
sbQuery.Append("</viewfields>");
sbQuery.Append("<queryoptions>");
sbQuery.Append("<viewattributes scope="\">");
sbQuery.Append("</queryoptions>");
sbQuery.Append("</mylistitemrequest>");



//the key here is the Scope= RecursiveAll will return all folders including subfolders.
//string query = "1";


XmlDocument doc = new XmlDocument();
doc.LoadXml(sbQuery.ToString());

XmlNode queryNode = doc.SelectSingleNode("//Query");
XmlNode viewNode = doc.SelectSingleNode("//ViewFields");
XmlNode optionNode = doc.SelectSingleNode("//QueryOptions");

XmlNode retNode = _lists.GetListItems(listname, string.Empty, queryNode, viewNode, string.Empty, optionNode, string.Empty);


return GetItemId(retNode);