The Iowa Natural Resources Commission has approved a contract to conduct a survey for four plants that are listed on the federal register of threatened species. Spokesman Mick Klemesrud says the University of Northern Iowa will conduct the survey. The four plants are Mead’s Milkweed, prairie bush clover and eastern and western prairie fringed orchids.He says the goal of the survey is to get a better idea of where the plants are growing and how strong their populations are. He says they’ve found some of the plants they didn’t know existed.U-N-I will be paid over 27-thousand dollars for the yearlong survey.