My yard has a massive number of squirrels and chipmunks and they run around all day summer and winter. I've never seen them eating any plants.
We have a big Oak tree and LOTS of acorn caps in and on the dirt, but never any acorns and near zero Oak seedlings. So I expect squirrels are very fast at finding acorns and discarding the caps.
Beyond that, they dig in the dirt a lot, generally far from growing plants and seem to find something to eat, but it is hard to tell what. I hope it is bugs. I planted a lot of Hardy Hibiscus seeds last fall (gift from a friend). I saw that a squirrel found some of them. ZERO have sprouted this spring so more likely squirrels found all of them.
But anyway, based on the behavior I observe, I don't think squirrels are munching through the base of plant stems, the way I know rabbits do.
