To: kansas gardener 2008's question "...do squirrels do this kind of damage???"
Yes! To illustrate a real, live case: I live in the S Jersey area, a holly haven and lots of grey squirrels. About 2 mos. ago I noticed a prize holly tree, with the red berries, a tree of about 25' and located about 30' from my house, beginning to appear slightly bare...and increasingly bare as time went on, like it had a blight. Following focused attention, it didn't take long to find the cause. The tree was being worked over by 2 grey squirrels. Usually right at or after daybreak, I'd find 1 or both of them perched or hanging on branches, eating the berries...chewing through leaves and clusters of leaves in the process; the debris (leaves, leaf clusters, and even with berries) simply fell to the ground as discards. The little beasts were chewing and eating their way through the tree! Simple loud clapping from an open window would usually scare them away immediately or within a minute or so. That's not the cure for obvious reasons (too bad I couldn't hire a local red fox or hawk to post guard and keep the squirrels at a distance). Researched and did some thinking and analysis of my own. I had tried several of the simple, usual deterrents, without overall desirable results to date. If you've watched the Star Trek Next Gen series, you're familiar with the insurmountable "Borg". These 2 squirrels show similar behavior...they "adapt" to countermeasures and render them "futile". Keep in mind, however, that I am not using any measures to physically harm them. Two most promising approaches appear to be: (1) trapping and relocation to >3 miles away [by an approved process and within local ordinances, needless to say...and keeping in mind that squirrels have young ones in the nest twice a year who need "mother".] If you've got a lot of squirrels, relocating them could be a daunting task. (2) psychological strategy: install a feeding station (for the squirrels) away from the area you want them to avoid with the hope of training them to stay away, creating a win-win for both you and squirrels [once again, within the ordinances of your locale; some areas have unusual regulations on feeding or interfering with wild animals]; but, that's the world we live in today. Both of these "more promising" cures can be costly. One other possibility...don't plant foilage that they feed on as a trade-off (won't help much with my native hollys). Good Luck partner...