A recent study, published in the journal Science, tells us that the restoration of vast tracts of tree cover is going to be one of the most important ways of battling climate change. Globally, an extra 500 billion trees could cut atmospheric carbon by about 25%.
The BBC, and others, leapt to the conclusion that we should rush out and plant billions of trees. There are government grants available to buy trees, tree guards and stakes, and charities spend time and effort promoting and delivering tree planting projects.
So it must be right to plant trees, right?
The authors of the original article don't actually mention tree planting (in the abstract, at least!), they talk about the 'restoration of trees' and 'extra canopy cover'.
But everywhere I go in the lowland UK, trees are trying to grow by themselves! Hawthorn seedlings are sprouting in our garden, willow soon takes over abandoned pasture. I have removed countless pine and birch trees from our special heathland nature reserves. Woodlands, without too many deer, regenerate naturally, with seedlings growing in clearings created by fallen trees. Jays spend much of their time burying acorns for when food is scarcer, only to forget where they are and allow them to germinate across playing fields.
So, in many cases, we shouldn't be importing trees that might be infected with Ash Dieback or Oak Tree Processionary Moth - or the next undiscovered tree disease. We shouldn't be using peat to grow seedlings and plastic tree guards to protect them.
Maybe we should focus our efforts on allowing natural processes to lead the way when it comes to woodland creation (cf Rewildling!). Individual trees are likely to be much better suited to the local environment, and the species composition of a naturally regenerated woodland is more likely to reflect those around them. Trees that are self-seeded often outgrow their planted neighbour.
Clearly, tree planting is appropriate is some places. Urban areas may struggle to regenerate their own woodlands, and the uplands, now often entirely denuded of trees, will need a helping hand.
I have recently visited a golf course in the Chilterns. The managers of the golf course had, last year, removed some scrub (which had regenerated naturally over the preceeding years).
These areas now abound with orchids and knapweeds and marjoram and oxeye daisies and St. John's-wort and a host of other flowers and buzzing insects. I asked the course manager what wildflower seed mix they had used, and he told me that they had sown a mix of three grasses, and that was it.
All of the other plants had either lain dormant in the seedbank or migrated from neighbouring meadows.
When regenerating 'wildflower' meadows, maybe we are too hasty to buy and sow wildflowers, as we are with planting trees.
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