They seem to wreak havoc wherever they go. One morning it took about five minutes to get to my car due to a pine squirrel standoff. The squirrel thought the garage was its territory. They made a nest in our garage (recently removed) and they chewed the wiring on a pickup truck my husband once had, leaving it inoperable. $$. An adult squirrel's incisors never stop growing, and they must gnaw on things to keep their teeth short. I don't care if they chew on stuff, I just don't want it to be at MY house.
Pine squirrels weigh between 1/3 to 2/3 pounds. They are very territorial and will protect their territory as a pair when they are mating. The pine squirrel usually has an average of four kits per litter. The northern squirrels usually have one litter per year. Natural enemies of the pine squirrel are bobcats, domestic cats, owls and goshawks. Let me add cars to that; just last week I saw the crows feasting on pine squirrel roadkill.
This tough little rodent has proved to be quite adept at adapting to their environment. I guess I'll still be digging mini-walnut trees out of my flower beds next year and for years to come.
(I didn't take the above photo -- it's 'borrowed' -- there's no way I'd get that close to a pine squirrel.)