The aim of this paper is to analyze seminal papers about environmental ethic that were published in 1970s in the United States of America. In my opinion the main points of controversy are need for a new ethic, moral standing of natural objects and naturalistic fallacy. The papers I selected here are following five ones: R. Routley, “Is There a Need for a New, an Environmental Ethic ?" ; J. Feinberg, “The Rights of Animals and Unborn Generations" ; C. D. Stone, “Should Trees Have Standing ?" ; K. E. Goodpaster, “On Being Morally Considerable" ; H. Rolston Ⅲ, “Is There an Ecological Ethic ?" Although there are some unsettledness or unclearness in those papers, it is certain that their main ideas had a great influence on the formation of philosophical environmental ethics.