Richard Eltringham (Letters, 5 August) argues that climate change necessitates switching to a planting palette of drought-tolerant non-native species. It’s not as simple as that. Horticulturists focus on the value of non-native plants for pollinators, but other ecological interactions (for example, food plants for insect larvae) are harder to replace. Native oaks support 2,300 other species; drought-adapted non-natives can’t substitute for all these interactions.
Our native species themselves aren’t tied to a preindustrial climate; there is evidence of rapid microevolutionary changes in oaks in response to recent climate change, so those crisping saplings might be part of selection for drought adaptation. Alternative planting palettes don’t offer a panacea – Mediterranean landscapes are rather brown in summer precisely because of plants’ adaptations to hot and dry conditions, while our dull, wet winters adeptly kill many drought-tolerant species.
Our climate is changing. But a kneejerk shift away from native planting might make things worse.
Martin Sullivan
Professor of global change ecology, Manchester Metropolitan University
I am puzzled by Richard Eltringham’s suggestion that we should move towards planting non-native species in gardens and parks to cope with increasingly hot and dry summers. Despite current moves towards wildlife-friendly gardening, the majority of plants in these spaces are already exotics, some of which are well adapted for drought, others less so.
Many native plants are also drought-tolerant, and it would be a pity to discourage people from attempts to make their garden more attractive for native insects by using plants that provide for all stages of their lives rather than just adults looking for pollen.
By all means adapt planting to cope with the changing climate, but don’t assume that this means abandoning an admirable trend towards planting native species.
Lorraine Du Feu
Cheltenham, Gloucestershire
