Cases of a deadly tree disease that causes ash trees to die back have been found in Kent and Essex, the government said on Monday. There are now a total of 82 confirmed sites, up from 52 as recently as this weekend. Defra stressed that it did not believe the new cases had necessarily spread from East Anglia, but may have been present in the environment already, with the spores born on the wind from the continent, where the disease is widespread.

But a shortage of botanists is adding to the problem of dealing with ash dieback. Diane Hird of the University of Bristol, who led a report into plant pathology education and training in the UK, said there had been a “serious decline” in the teaching of and research into plant diseases in the UK, going back for two decades.