Cheyenne Light, Fuel and Power, in partnership with Leadership Cheyenne, Rocky Mountain Landscaping and the City of Cheyenne, planted trees at David R. Romero Park in south Cheyenne Friday and again on Sunday in celebration of Earth Day . The plantings focused on the official State Tree of Wyoming, the Plains Cottonwood. Because the cottonwoods are native to the state they are better able to resist drought, insects and disease than many other trees not native to Wyoming. One cottonwood was planted Friday, with 35 others scheduled for Sunday, according to Cheyenne Mayor Rick Kaysen.