UK wild flowers face extinction

THE UK countryside is being overrun by nettles and hogweed because pollution is killing off wild flowers.

“Thuggish” plants which thrive on the nitrogen pumped out by diesel cars and industry are overpowering more delicate flowers such as harebells, a report warns.

More than a third of flowering plants struggle in nitrogen-rich soil, which can leave them more vulnerable to drought, frost and disease.

The charity Plantlife says the delicate blue harebell, a bumblebees’ favourite, recently classified as near-threatened in England, is one of those at risk.

So too is the bird’s-foot trefoil, a yellow member of the pea family named after its flowers’ resemblance to birds’ claws.

Orchids, dependent on fungi which is extremely sensitive to nitrogen, could also be in danger. The research, conducted with support from Lancaster University and backed by the National Trust, says 37% of Britain’s flowering plants prefer low-nutrient conditions, putting them at risk from nitrogen, which also leaches into the soil from agriculture.

Dr Trevor Dines of Plantlife said: “Nettles, hogweed and hemlock, thuggish species that thrive in soil steeped in excess nitrogen are drowning out rare and more vulnerable wild plants.”

Concern is building over diesel fumes, with the toxic nitrogen oxide particles they produce linked to the deaths of 23 500 people in Britain every year. But nitrogen also gets into the soil, deposited directly from the air or in rain.

Normally essential to plants, because it helps them to grow, excess nitrogen can be too much. While nitrogen emissions have been cut in the past 20 years, the study says it could take decades for soil to return to normal.