According to studies conducted by the forest service, this tarping technique is 100% effective against the disconcerting habit of marmots to chew through vehicle hosing coming in from underneath the vehicle. The technique more commonly used is to leave the hood of your car popped -the theory is that the marmots won't chew on the rubber unless they're in a confined space like when the hood is down. Leaving the hood up worked in the case of Tom's car. Popping the hood is certainly easier than dressing your car in tarp or chicken wire. Seen at Sawtooth Trail trailhead in Mineral King, 7.20.08.