From the damage and the pics it looks like dogwood sawfly. Here's a link:https://www.whatsthatbug.com/2008/08/09/dogwood-sawfly-larvae-2/
But if you can bring them in to your extension office in a vial of rubbing alcohol they can identify it for you more accurately:
- Address: 12011 Government Center Pkwy, Fairfax, VA 22035
- Phone: (703) 324-5369
Thanks so much!