I wholeheartedly support the idea of increasing the amount of woodland we have i n Britain, especially in England, which is very thinly forested by northern European standards (Restore UK woodland by letting trees plant themselves, says report, 15 December).
But the problem with “just letting nature get on with it” is twofold: first, ecological succession takes a long time. And second, Britain now contains so many invasive plant and animal species that we may never get the resulting forests we hope for through a policy of benign neglect. In other words, some management will always be required.
Consider the sycamore tree, an incredibly fecund species now common in every corner of these islands. Just four centuries ago, it was all but unknown in Britain. Unfortunately, there are very few insect species associated with sycamore, and no fungi, so the native fauna derive almost zero gain from this species. Moreover, a hillside that is thick with young sycamore saplings denies water and light to slower-growing competing trees. Compare this with the beech – another non-native species that has naturalised here, but one that is far less fecund and has a huge number of associated insect and fungi species. Beech only thrives in particular soils, but sycamore will proliferate almost anywhere.
In other words, if we want to maximise biodiversity in our wild spaces, we need to consider what grows there, and what food webs and habitats are built and supported. There is no guarantee that nature, unassisted, will arrive at a desired outcome.
• Whether new woodlands are planted, or generate themselves as recently recommended by Rewilding Britain, their success will not be maximised unless there is a parallel strategy on the control of our deer populations. The simple fact is that there are far too many deer and they are incredibly destructive of young trees. It may be difficult to convince the animal-loving British public that deer need culling in large numbers, but unless that happens many tree-planting initiatives will be hampered by either deer predation or the high costs of expensive fencing. Perhaps a good place to start would be to extol the merits of venison as a far healthier meat than that from factory-farmed livestock. There’s a venison supply chain out there just waiting to be exploited for the common good.
• Rewilding Britain’s report on natural regeneration of woodlands by seed is welcome but hardly new. As Oliver Rackham wrote in his 1986 book The History of the Countryside: “Tree-planting is not synonymous with conservation; it is an admission that conservation has failed.”
Tree-planting is generally viewed as a good thing. It is measurable and responds to target setting, but it requires a lot of much less sexy follow-up – maintenance, irrigation, and protection from browsing animals – much of which doesn’t happen, with predictable results. The success rate of planted trees is hugely variable but we are all aware that many fail.
Trees growing from seed, in situ, will grow better, faster, more securely rooted and suited to the prevailing conditions. They are genetically varied, much less prone to disease, and of course they are not bringing in diseases from elsewhere. They will grow to a shape moulded by the environment rather than being uniform, straight-trunked and dull. Let’s give them a chance.
(Chartered landscape architect), Bristol
• The recommendations of Rewilding Britain should be quickly taken up by the government. The current drive to plant trees is funding forestry companies to plant 65% Sitka spruce, grown as a timber crop with little benefit to wildlife or biodiversity.
Despite widespread knowledge about carbon capture within soil, Scottish moorlands covered in shallow to deep layers of peat are being ploughed and planted with swathes of these trees at an alarming rate. The landscape is being transformed into industrial monoculture plantations, without much hope of reducing climate change. We must stop this before it is too late.
Langholm, Dumfries and Galloway