But by providing social proof that others were stealing, the message had a perverse effect, almost doubling the number of people taking wood! Highlighting what people should do was much more effective. Over a different set of trails they tried a different sign that stated, “Please don’t remove the petrified wood from the Park, in order to preserve the natural state of the Petrified Forest.” By focusing on the positive effects of not taking the wood, rather than on what others were doing, the park service was able to reduce theft.
