Type mismatch?

[dColumbus]

why is this a type mismatch?

var stump = trees.splice(t, 1);

here’s the code:

 function uproot(t_id:Number) {
 for (var t in trees) {
  if (trees[t].id == t_id) {
   var stump = trees.splice(t, 1);
   stump[0].obj.delMovie();
   delete stump[0].obj;
   stump[0].obj = null;
   delete stump[0];
   stump[0] = null;
   delete stump;
   stump = null;
   trace("Tree ["+t_id+"] UPROOTED, remaining:"+trees.length);
  }
 }
}