Tree planting is one of those motherhood-and-apple pie policies that it’s quite hard to argue with. We have a climate crisis, and a dreadful decline in biodiversity, and more trees will help with that. They will restore our denuded landscape to something more natural, and they’re good for our mental health. Only a curmudgeon could carp about tree planting, which is presumably why the main political parties spent the last election having a plant-off about how many trees they want to get in the ground.
The government has a target of 30,000 hectares a year across the UK by 2025, and Boris Johnson has been linking his tree ambitions to all kinds of other problems. Last week, he said he wanted the government to move faster with its planting programme to fight the risk of floods.
There’s a cross-party consensus on the need to plant new trees, and why wouldn’t there be? Who can argue with a tree? Plenty of people, it turns out – and many of them are the ones politicians should be listening to. In fact, the first sign that there might be a problem with a policy is when all the main parties feverishly agree on it. Consensus in politics sounds lovely, but often leads to lazy thinking and a refusal to examine whether a policy really will work as well in practice as in the imagination.
This week, scientists at Kew Gardens warned that tree planting can actually damage the environment. In a paper published in the journal Global Change Biology, the researchers warned that:
‘Tree planting that is poorly planned and executed could actually increase CO2 emissions and have long-term deleterious impacts on biodiversity, landscapes and livelihoods.’
Their study covers reforestation projects across the world, but in the UK we’ve had a number of serious incidents in the past few years where trees have been planted in totally inappropriate places.