i avoid trees as much a possible. the parking lot @ my co. has these horrendous sap-drippers. the only clean spots are right next to the entrances or @ the end of the lot. if i don't get a spot up close, i'll head to the end of the lot - long walk, but less work in the long run & saves the paint as well.
plus, not good when sap gets moist - it expands & smears when you try to run the wipers, making visibility out windshield difficult (used to park under trees in old honda - learned my lesson then.)

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