I’ve had two carpenter ant infestations in my house over the last couple of decades, and the giveaway was piles of sawdust. That doesn’t look to me like the result of carpenter ants. I can’t speak to termites.

You haven't seen any ants or termites? They should have appeared by now if they're present.

I’ve seen one ant in the basement occasionally I’ll see one on our deck. Never seen a termite, but our home inspector mentioned that our home was being treated for them before we bought it.

Was the ant you saw a carpenter ant? They are rather large and have distinctive stripes on their abdomens. They also typically walk along particular paths in a “caravan.”

I am about 99% sure, but haven’t ever seen more than one of them at a time. Now the question is, if this isn’t frass, what on earth is it? Homeownership is great!

Nicole-

Could be frass...just not from something harmful, or at least as harmful as carpenter ants or termites.

The first pix looks like it could be bits of pine tree blossoms caught in spider webbing. Any pine trees on the property or adjacent to?

No pine trees on the block to my knowledge. Exterminator said it could be from pavement ants. He found a bunch of them just outside the house around this spot. Thanks for the help, everyone.