bthiede wrote:
I recently killed, tilled, then reseeded my lawn (3 weeks ago). The
grass came in OK, but there are still lots of bare areas. What can I
do about this? Can you overseed new seedlings, or will that risk
overcrowding them and killing what I already have? Could I just
selectively overseed the bare areas? Or should I just wait until
spring to overseed?

You still have time since fall just started to overseed the bare areas.
Unless there is too many bare areas and then I would overseed the whole
thing. Weeds could trickle in if you wait till spring. Make sure the
seed is getting adequate moisture. Once the seed gets wet it needs
continual moisture to grow or it will dry out and die. Are you able to
mow it yet?
Sue