I am fairly certain that a resident pair of Brown Thrashers (birds) have been cracking off the tops of some scapes (laying on ground right beneath the scape), not to mention making a mess of the bark (hence their name).
But Cottontails are the most likely culprit for these buds that have been eaten. They have been rampant in my general area. Two years ago a group of hunters visited my neighbor's place across the street and in 1 hour had 26 rabbits bagged. Not that bad now, in fact I've only seen one or two at my place lately-- but that is all it takes...
It could be that deer ate the buds, or both rabbits and deer, but normally I can see the deer tracks.
My motion-activated sprinkler seems to be effective protecting one area, so I may try moving it from spot to spot. Also re-sprayed deer repellent on everything (not sure how long I can keep doing that since that stuff is so expensive). And will probably put down more blood meal and milorganite.
I'm considering building a 10' block wall, and a moat, around my entire place but the cost of putting in the drawbridge is holding me back...