This afternoon (10/1) we found a Clay-Colored Sparrow at Bates Nut Farm in Valley Center. It was foraging with a group of Chipping Sparrows just at the main entrance near the enormous coast live oak.
Bates Nut Farm is open to the public from 9am to 5pm everyday, although on weekends in October it is swarmed with people-- hence why most of the birds were up near the entrance, away from the activity.
Photos in eBird later.
--Aedyn and Trysten Loefke