EcoWatch: The U.S. Environmental Protection Agency (EPA) has approved a final rule which would allow for biofuels made from two well known invasive species to qualify for credits under the Federal Renewable Fuels Standard. The rule, which was finalized late Friday afternoon, allows two invasive grasses, Arundo donax (also known as giant reed)--assessed by the U.S. Department of Agriculture as being a high-risk species--and Pennisetum purpureum (commonly called napier grass), to qualify as cellulosic biofuel...