- A POSTnote on reforestation will summarise the strategies for identifying optimal areas for successfully restoring woodlands and the possible means of incentivising this.
- It will look at the evidence for the optimal approaches for providing climate and biodiversity benefits, and the challenges that will need to be addressed.
- Provisional start date: September 2020. To contribute expertise, literature or as an external reviewer, please contact Dr Jonathan Wentworth. View our guidance for expert contributors.
Most IPCC scenarios rely on large-scale, land-based mitigation measures such as reforestation to meet the Paris Agreement objectives. Restoring forest involves increasing tree cover on previously forested lands through active planting or natural regrowth. Active replanting has higher costs per unit area than natural regrowth but is needed where forests are unable to regrow naturally or if restoration of the community of undercanopy plants is required. Climate NGOs have suggested the UK Government is “failing in its legal duty to create adequate reserves of growing trees” as set out under the Forestry Act 1967. They suggest government should double tree cover in England from the existing 13% to 26% to sequester 37 MtCO2e per year by 2045. This includes prioritising the growing of broad-leaved woods on Grade 4 land that is close to where most people live in towns and cities to maximise societal benefits. The Committee on Climate Change has called for 1.5 billion new trees by 2050, requiring planting on 30,000 hectares (74,000 acres) of land a year, increasing Britain’s forest cover from 13% to 19%, much of which would be commercial forestry.
However, a report produced for the RSPB has suggested commercial tree plantations do not store carbon because more than half of the harvested timber is used for less than 15 years and a quarter is burned. This runs contrary to previous assumptions that commercial timber uses result in storage, such as use in buildings that can lock carbon up for decades. Of the UK’s 2018 timber harvest, 23% was used for wood fuel, while 56% was taken to sawmills. Only 33% of the wood used by sawmills was for construction, whereas a higher proportion was used for fencing (36%) with a service life of 15 years, or packaging and pallets (24%) or paper (4%). The report notes that broad-leaved woodlands planted in the right locations and left intact would be optimal for carbon storage and biodiversity, but this could displace demand for timber to other countries with undesirable outcomes. Reforestation could also negatively affect biodiversity, food production and water demand if trade-offs are not considered when planting is planned.
A POSTnote on this subject will summarise the strategies for identifying optimal areas for successfully restoring woodlands and the possible means of incentivising this, the evidence for the optimal approaches for providing climate and biodiversity benefits, and challenges that will need to be addressed.