The government was warned three years ago that the rampant disease killing Denmark’s ash trees was likely to spread to Britain and devastate UK woodland but failed to act, it has emerged.

Emails exchanged between Britain’s garden industry body, the Horticultural Trades Association, and senior civil servants in the Department for Environment, Farming and Rural Affairs (Defra), show that the government knew about “ash dieback” and was asked to impose an import ban on all ash trees from Europe, but did not believe a ban was “appropriate”.

DEFRA replied saying that because the disease was already endemic [in the EU] it was likely to come to the UK. They felt that controls were not appropriate.”

Under EU food and health rules, government could have made Britain a “protected zone” and stopped any ash trees being imported. But Defra’s decision not to further check whether the Danish pathogen was the same as the one thought to be present in Britain suggests it either did not take the HTA experts seriously or felt that the disease would not cause serious damage.