Try Goof Off spray (not the pour-on stuff; that's a bit messy), leave it on for a minute, then wipe away, wash the car and apply a coat of wax ASAP. There was a lot of pine trees at my old job and I DREADED parking under them, but sometimes it was the only spot available... Not to mention... I admit, it's right outside the window so it makes it worth it for me to be able to stare at my car whenever I please
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