The Prince was given a guided tour of the facility, which is exploring how forest systems will respond to future increases in atmospheric carbon dioxide, including the effects on forest growth and on forest food webs.

His Royal Highness unveiled a plaque to mark his visit, which comes 12 months after the experiment began. The Prince was given a bottle, recovered from Mill Haft woodland in Staffordshire during construction of the BIFoR FACE facility, which containing a sample of the air used in the facility. The air contains 150 parts-per-million more carbon dioxide than UK air in July 2018. This elevated concentration of carbon dioxide will be the planetary norm by the middle of the twenty-first century, and is used at BIFoR FACE to test the resilience of the forest system to the very substantial environmental change our forests are experiencing. Geological research indicates that it is tens of millions of years since Earth had this much carbon dioxide in its air on average.

BIFoR FACE is a Free-Air Carbon dioxide Enrichment facility, in which the carbon dioxide level of forest air is elevated without enclosing the experimental patches.

In his speech, the Vice-Chancellor of the University of Birmingham, Professor Sir David Eastwood said: “We are honoured to welcome His Royal Highness here today to join us in celebrating the critically important work being carried out here. As the concentration of carbon dioxide continues to grow and as visions for sustainable growth recognise the need for increased forest coverage, only ambitious experimentation such as that at BIFoR FACE, can provide the robust evidence-base for decision-making on how to manage our scarce land resource.”

BIFoR Director and academic lead for the FACE facility, Professor Michael Tausz, said: “It has been a privilege to meet His Royal Highness The Prince of Wales today and show him our progress at this early stage. After only a single growing season, we have learnt how dynamic the response of a mature forest is to elevated carbon dioxide. As we continue this decade-long experiment, we will quantify the carbon budget of a mature forest in great detail, contributing to the global narrative on climate change and the national conversation about sustainable land management.”