Seeing the carcass of one their cousins just might make them think twice before visiting again.
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Sorry, but I do not think they are that bright.
There are a lot of strategies you can find online, though, for fending off the beasts.
One of my chief filters in searching for plants to use in my yard is “deer resistant”.
Thanks. Strategy works for squirrels though. This is the first season I have had pears in about 5 years.