New Post: Deleting programatically created column

I have created a column programatically but I m not able to delete it either programatically or through UI. Please help. The code is below:
var sn="Name";
var dfields="<Fields><Method ID='1'><Field Name='"+sn+"'/></Method></Fields>";
alert(dfields);
$().SPServices({
operation: "UpdateList",
listName: "dum",
deleteFields: dfields,
completefunc: function(xData, Status)
{
alert(xData.responseText);

}
});