Thirty-year 'Witness trees' project to see which are best at cleaning our air

Trees make wonderful natural witnesses to environmental change as they are generally very long-lived and they are highly responsive to their environment

Scientists enlist 'Witness Trees' to track climate change and pinpoint which species can best clean our air. At the National Botanic Gardens, Glasnevin, l-r: Sate Ahmad, Christos Chondrogiansis, Jenny McElwain, Tina Monterio, and Morgane Weissenburger

Scientists here are investigating which trees are best at cleaning our air by filtering out dangerous smog from the atmosphere.

It’s a 30-year project so these ‘Witness Trees’ will help track how climate change is progressing in the coming decades.