What’s eating my apple trees?!

I have a few little apple saplings growing in pots. Two have had their growing tips sheared off by something, I suspect a caterpillar.  I applied a pyrethrin/neem spray with added capsaicin in case it was a mammal.  Now, less than a day later, the culprit has returned and sheared off even more growing shoots!  They look like someone just primed them off (not a person - I live in the middle of nowhere).  Any ideas?

I’m in Northern California.

Deer I think because it is such a clean cut.  I think rabbits are chewier.

If you can, set up a game camera, the cut I can see in your photo doesn't look like a deer bite mark (deer only have upper teeth so there is usually a "tag" in the middle of their bite marks).
With out a reference, I can't really tell how tall these saplings are so I can't rule out rabbits. Rabbits will make clean cut lines and they sometimes take off whole leaves to take home with them for a late night snack.