Black granular debris?

I have some odd black granular debris that I have NO clue about. Might be bugs? Moderators please move this if you have better guesses than I do

I clipped some tent caterpillar infested branch ends off yesterday, left them on the ground overnight. A few got tossed onto a sheet of plastic. When I picked up the branches this morning, on the plastic was a LOT of black granular stuff. Little bitty pieces, all about the same size, mostly just kind of in little drifts, one area probably 2 tablespoons full in a pile. The tree this was under is a walnut. Not knowing what it was, I put the plastic in the trash, but failed to take a picture.

My theories run the gauntlet of tree droppings, bug droppings, bug eggs, tent worm eggs, wasp poop etc. No really solid guesses. What IS this? I assume it was on the ground too and I just didn't see it.

Thank you for any help on this, I hate not knowing if I should be freaked out or not

It's bug droppings. Nothing to be freaked out about. Here in MA it's under all the oak trees, everywhere.

Agreed. Caterpillars can poop A LOT. They need to eat a lot to get ready to make their cocoons.

Kind of funny story; A month or two ago we found what looked like mouse droppings on our countertop and what looked like a couple mouse chomps out of our bananas. We have never had mice in our house but they are all over outside. I was pretty bummed they finally made their way inside but we had a trap so we set it out. Well the next morning we discover that it wasn't actually a mouse but a giant green caterpillar that had found our fruit on the counter. It was eating the skins of the bananas and avocados because there were no leaves in the house to eat.

Anyway, point of the story is that the caterpillar's poop was so big that it looked like it came from a mouse! I would have never imagined that those poops could have come from a caterpillar but I'm glad it wasn't a mouse...

That's... wow.
Thank you!! (I think)