Claire Sheedy, 4, of Waukesha shows how much she loves Earth Day by hugging a pine tree Thursday at the Retzer Nature Center in the Town of Genesee. Children at a nature hike and holiday celebration were asked to find a tree to examine closely in Retzer's red pine plantation. Former Wisconsin governor and U.S. senator Gaylord Nelson created Earth Day on April 22, 1970, to draw attention to environmental perils.