Most often, the best treatment for an infected wild forest is to leave it alone, writes beloved naturalist Richard Mabey.
An insidious anthropomorphism governs our relationships with trees, from beliefs about their conception to judgments on their health. We persist in regarding them as frail humanoids in need of intensive care, not as autonomous organisms. For at least two centuries trees have been rebranded as the products of human enterprise, and their existence predicated on our behaviour as surrogate parents. We must plant, stake, weed them, employ hygienic or cosmetic surgery if they are to survive, and put them out of their misery when they don’t pass our tests of worthiness. What we shut our eyes to is that this pattern of ubiquitous, regimented intervention is part of what makes them susceptible to trouble. ….
A wood without any diseases or parasites would be a lifeless cohort of leafy poles. No leaf-eating insects, therefore no insect-eating birds. No rot-holes for bats and owls. No timber recycled back into the soil. Trees are social organisms. They tend to live with other trees, in a complex network of mutual dependency. They are linked by chains of benign underground fungi that distribute nutrients and information about insect predation, and which one ecologist has nicknamed “the wood-wide web”. If one species of tree succumbs to stresses, other species take its place. In individual trees, reduced vitality prolongs life. What we regard as “diseases” are often just the intricate exchanges and workings of the forest food-chain.
Exotic diseases, to which these exquisite networks are not adapted, are the exception, and there is no conceivable argument against a total ban on imports of tree material from areas where non-native afflictions are rampant. But we should reflect on how the ways we manage trees and woods provides conditions as conducive to epidemics as an overcrowded hospital: battery-grown saplings with minimal genetic variety; dense block planting with single species, often in unsuitable sites; suppression of natural regeneration; ignorance of trees’ natural immune systems and survival mechanisms. At every point we are the cause and aggravator of malignant tree diseases, but it is natural woodland that is likely to be the remedy.
Richard Mabey, “Wildwoods don’t need our help to survive ‘apocalyptic’ diseases“, Financial Times, 27 June 2015 (metered paywall).
UK nature writer Richard Mabey (born 1941) is author of numerous books, including Weeds: In Defense of Nature’s Most Unloved Plants ( Ecco, 2011).