Most people under the age of 40 will never have seen the elm landscapes so loved by Constable or Turner. They may have read John Betjeman's eulogies to the English elm, and might even have heard of the ancient elm under which John Wesley reputedly preached in Stony Stratford. (I am currently growing an elm sapling, taken from that great tree before it was finally removed a few years ago).
But they won't have actually seen any of these wonderful trees that once graced the British countryside. For they were wiped out in their many millions from the 1970s, when a virulent strain of a fungal disease arrived on imported Canadian logs and fanned out from ports in Bristol, Southampton and London killing between 25-30 million trees.
EDIT
Aside from East Sussex and the Isle of Man, the only recorded English elm survivors in Britain are two remarkable trees in an isolated spot in the Cotswolds, and an old tree that graces a graveyard near Dervaig on the Isle of Mull in Scotland. But this has been a very bad year for Dutch elm disease, possibly one of the worst since the mid 1970s. To the east of Brighton, in the beautiful elm landscapes of the South Downs, almost every hedgerow is showing the tell tale signs of the disease; yellowing and browning leaves, and rapid die back.
EDIT
http://news.bbc.co.uk/2/hi/programmes/newsnight/8912727.stm