Tree planting could save planet but local ambition must be stronger

Planting trees is the ‘best climate change solution available today’, according to research into the impact of mass reforestation worldwide.

Researchers at ETH Zurich university found that Earth’s land could support 4.4 billion hectares of continuous tree cover, 1.6 billion more than the existing 2.8 billion hectares. Of these 1.6 billion hectares, 0.9 billion hectares are not being used by humans. This means that there is an area of the size of the US available for tree restoration. 

The study’s lead author Jean-François Bastin said: “One aspect was of particular importance to us as we did the calculations: we excluded cities or agricultural areas from the total restoration potential as these areas are needed for human life.”

Once mature, the new forests could store 205 billion tonnes of carbon: about two thirds of the 300 billion tonnes of carbon that has been released into the atmosphere as a result of human activity since the Industrial Revolution.

The findings were published in the Science journal and while the positive effect of tree planting on the environment has long been well known, this is the first study that identifies areas that could be reforested on such a grand scale. Unsurprisingly, countries with large land masses had the greatest potential for reforestation: Russia, the US, Canada, Australia, Brazil and China.

In the UK, the creation of new woodland forms part of the Government’s target of net zero emissions by 2050. Last year 13,000 hectares of new woodland were planted – almost all of that in Scotland. The Woodland Trust pointed out that England’s contribution was woefully short of what’s needed to fulfil the 2050 goal: just 1,400 hectares created against a target of 5,000.

The trust’s director of conservation, Abi Bunker, said: “The UK needs renewed ambition when it comes to tree planting and woodland expansion. The scale of what needs to be achieved to reach net zero targets is obvious; it will necessitate a three-fold increase on current levels.”

Local authorities’ tree strategies can have a positive impact on the country’s tree planting targets. Hartlepool Borough Council, for example, has one of the lowest percentages of tree cover in England at 2.6% compared with a national average of 8.6%. It is using planning guidelines to bring coverage up to at least the national average.

“While trees may affect the development potential of some sites, in many cases they can be successfully integrated into new development schemes. Socially and environmentally responsible built environment professionals understand that the retention of trees within new developments provides an immediate sense of maturity, to the benefit of a site and its surroundings, raising the overall quality of schemes and enhancing property values,” the council says in its tree strategy.

Hartlepool’s tree strategy is cited as an exemplar by the Woodland Trust. Read the trust’s guidance for local authorities on creating tree strategies.