Has to be deer.
Here is a link with pictures:
http://www.ppdl.purdue.edu/PPDL/weeklypics/1-10-05.html
the bottom photo shows crow damage.
The crows seem "neater", but would not be doing this in the dark, like the deer do.

Little rodents like voles do come out at night too, but they
could not sweep thru like that. Squirrels are daytime animals.
Rabbits cannot reach high up.

Ground hogs may get the lower ones, and they do climb but are so heavy they would break or bend the stalks.

We had a deer surprise this spring. Since our front street was ripped out and dug for new water/sewer lines, there was sand
for several weeks before the paving was done. We found two
tracks of deer prints in the sand. Which explained the loss of my Mertensia. Being in a high density city, one would think deer would be unusual, BUT they are coming in commonly now.
We even have coyotes! This photo shows the sand where we found the prints: The front part of my rock garden is shown, as well as our cat, This dozer was parked for the night,
over a manhole which does not show...to protect cars from it since it was 12 inches higher than the road and thus a hazard.


P.S. I am here regarding your magnesium question at the other forum. If you are still undecided about it, now is the time to ask, as I will be leaving soon for about 8 wks for my summer vacation,( where I am unavailable on computers.)