This wasp (Sphecidae?) was dragging a very large grub over a log in an oak woods near a creek. She laid the grub down, removed a couple of objects blocking entrance to her nest (I assume) quickly pulled the grub down the hole, and then quickly gathered objects to close and (expertly) hide the opening. Though I had no opportunity to measure, I'd describe the wasp as medium large, and compare its appearance to Ammophila wasps I've seen in the area. I have no idea about the grub, it was considerably longer than the wasp.