Do Dying Trees Lead to More Human Deaths? The Debate Continues The emerald ash borer has been attacking all 22 species of North American ash trees in the last few years, killing nearly every tree it infests. Photo courtesy of Flickr user Flickr user Darkroom Daze. The hypothesis: Trees improve people's health. The experiment: Remove 100 million trees in the eastern and midwestern United States over the course of 10 years and see what happens. What happened ...
June 14, 2013 - The Online NewsHour