Dame Judi Dench was given an elm resistant to Dutch elm disease at the RHS Chelsea Flower Show yesterday

Half a century ago Britain’s 30 million elm trees were virtually wiped out, with fewer than 100 believed to have been left standing.

Now they are set to return with the introduction of a variety that is resistant to Dutch elm disease and which was publicised yesterday with the help of Dame Judi Dench.

The actress, a devotee of the trees who has planted saplings at her home in remembrance of friends who have died, attended the RHS Chelsea Flower Show to announce Ulmus “New Horizon”.

Dame Judi, 84, spoke passionately about the loss of Britain’s elms, which were a common feature of the countryside until the late 1960s.

Although there had been outbreaks of Dutch elm disease as early as the 1920s, it