From the roots up: more tree-planting will help UK meet net zero target

The Committee on Climate Change (CCC) – independent advisors to the government on building a low-carbon economy – last year recommended planting around 30,000 hectares (116 square miles) of trees each year until 2050 to help meet the net zero carbon target.

Planting trees in the UK has long since been in decline. At the apex of afforestation in the 1970s and 1980s when tax breaks incentivised it, the 30,000 hectares figure was last reached in 1989 but has since slumped to a low of 5,500 hectares in 2016.

Since 2016, there has been an increase to about 13,000 hectares planted in 2019 assisted by funding for new projects. In the March 2020 budget, £640m was allotted to a Nature for Climate Fund to increase tree planting and peat restoration in England over the next five years.

This equates to about 6,000 hectares per year, significantly less than the CCC’s target. In June, however, the government announced that they have targeted planting 30,000 hectares per year by 2025. Precise plans on achieving this will be released before the end of the year.

Tree planting plays an important role in meeting climate targets. Trees store carbon in the process of photosynthesis (producing food for the tree) and woodland soil is rich in organic materials. However, simply planting trees per se is not an answer to decarbonisation: longevity and tree types are also crucial factors.

Dieter Helm, chair of the Natural Capital Committee, warns about the downside of commercial forestry. Such plantations fall into a cycle of plant/rapid growth/felling where much of the carbon captured (80% is the estimated amount) is too soon released back into the environment thereby undoing much of the good work. Helm says there is a “danger of creating a carbon silo…which risks fixing one problem but inadvertently sparking a host of others”.

As for which type of tree represents the best option for the environment, the choice is essentially between conifer and broadleaf. Conifers – spruce, pine, etc. – grow quickly and are the choice for timber manufacturers. At the height of afforestation mentioned above, conifers accounted for 90% of trees planted.

Broadleaf trees – oak, beech, sycamore, etc. – grow slower but tend to be allowed to remain in situ and, as a result, ultimately prove more effective as carbon absorbers. The CCC recommend a split of 60:40 between broadleaf and conifer to achieve the optimum balance for carbon sequestration.

Nature is enhanced by the beauty of trees and the environment benefits: win-win for us all.