With many incandescent light bulbs made elsewhere now I'm wondering which factories in the USA are still around. Many of the Sylvania incandescents are made in USA. The regular incandescents and SuperSaver halogens it says made in St. Marys, Pennsylvania. The halogen flood lamps says made in Winchester, Kentucky so I assume those factories are still in operation. Are there any others still in operation?

Sure. Here are the following:

Ohio Lamp Plant (GE) in Warren, OH, they make reflector bulbs and rough service bulbs and other specialty lamps

Lexington Lamp Plant (GE) in Lexington, KY, they make sealed beam PARs, MR-16 halogen, and they share PAR-38 production with Ohio

American Light Bulb Manufacturing in Mullins, SC, they are owned by Aero-Tech, they make long life incandescent bulbs in general service and reflector types

DIC Tool Inc, also known as Meadville Lamp, in Meadville, PA, owned by Trojan Inc, they make similar products American makes at the Mullins facility.

Unfortunately thats a far cry from the 70s when there were over 30 incandescent lamp assembly plants.

Interesting. So what about the lamps that are supposedly made in St. Marys, PA?

   Dave, I'm searching around Meadville on Google Maps and Wikimapia trying to locate this lamp plant...and not having much success!

   I found this "DRS Sales" at the western end of Poplar Street...for some reasin this seems to match the "DIC Tool Inc" you mention, but it just cannot be a lamp plant, far to small, no glass furnace stack, no cryotanks etc. The place in Mullens had all those things, but here, I;m drawing up a blank.
   There are a few plants that could be big enough to be a lamp plant, two belonging to Channellock Inc, a manufacturer if pliers and other hand tools, SECO-Warwick, a furnace manufacturer and C&J Industries, an injection molding crowd....but none of these are lamps? How did you get the information that Trojan/Newcandescent was located in this town?

I learned that Trojan/Hytron bulbs are made in Meadville, PA from Roger Batchelor at Kayline, who has sold me those bulbs.