Pine trees may help create smog, acid rainThursday, 13 March 2003 Could pine trees be making things worse? Latest research suggests they contribute to smog Rather than being a global warming solution, pine trees may be inducing smog and acid rain by releasing vast amounts of nitrogen oxide into the air, researchers have discovered. Under some circumstances, needles from Scots pine trees can release nitrogen oxides directly into the atmosphere, according to a report in today's issue of the journal, Nature. A team led by Professor Pertti Hari of the University of Helsinki...