Why is northern Eriador (Lake Evendim, Fornost) deserted at the end of the 3rd Age?

[CSteefel]

But I am not completely clear why the Rangers would bother going up there if the place was completely deserted. I suppose they could be protecting against the possibility that Orcs and Wargs from the north would descend on the area, and then move to the south (Bree and the Shire).

But otherwise, why would the Rangers bother to visit a place that is completely deserted?? This is partly what sparked my interest in the topic...