We have to park our car under a walnut tree because there's nowhere else near the house to park. Last year there was a bumper crop in walnuts. Squirrels were everywhere! The check-engine light came on in our car and wouldn't go off. We took the car to our mechanic. When we picked it up two days later he said, "Craziest thing! It looks like something has been gnawing on all the hoses." It cost almost $400 to fix everything so the car would pass inspection. Darn squirrels!