BTW, even if anthropogenic global warming existed – which it probably doesn't, and there are other sources and scientists who point this out – planting trees would do next to nothing. To reverse the release of CO2 (if that were a real problem), it's not enough to plant one generation of trees to cover the Earth. It would be necessary to plant multiple generations and bury them, so as to put enough CO2 back underground to correspond to the quantity we are releasing.