Many tribal cultures used various forms of balm, lotions or salve to protect their skin from strong rays of the sun, a startling innovation for many Europeans. The Zuni used the western wallflower (Erysimum capitatum) as a sunscreen or sunburn treatment by mixing the ground plant with water and applying it to the skin. Southwest tribes treated sunburn with aloe vera, a popular treatment today. Northeast tribes used oil from sunflower seeds, while Indians living in what is now Pennsylvania used petroleum jelly thanks to their proximity to petroleum deposits.