The discovery of a mature ash tree in a Norfolk woodland which has fought off the aggressive ash dieback disease has offered new hope for the future of our forests.

%image(14832827, type="article-full", alt="The first UK native ash tree highly tolerant to Ash Dieback discovered at Ashwellthorpe. The tree has been named "Betty" by local researchers.Dr Anne Edwards from the John Innes Centre with the tree.Picture: James Bass")

Norwich scientists will today announce the major breakthrough in their research after identifying a healthy tree in Ashwellthorpe Wood, near Wymondham – nicknamed Betty – which has a strong tolerance to the disease, despite being surrounded by the infection.

It comes just weeks after a survey of the species, published in the Journal of Ecology, found the twin threats of ash dieback disease and the potential spread of emerald borer beetles, from Russia, could have a devastating effect on ash trees.

An alliance of scientists – the Nornex consortium – was set up after the deadly disease was discovered in the UK in 2012.

They have compared the genetics of trees, allowing them to predict whether or not a tree is likely to be tolerant to the disease, with Betty showing a strong tolerance.

Their findings could lead to 'selective breeding' to develop strains of trees that are tolerant to the disease.

Professor Allan Downie, emeritus fellow at the John Innes Centre and co-ordinator of the Nornex consortium, said: 'The identification of genetic markers for trees with low susceptibility to ash dieback is a large first step, one of many that will be needed in the fight to help ash trees survive this disease epidemic.'

He said it was 'astonishing' to have come so far in so short a time.

The UK's chief plant health officer, Nicola Spence, said it paved the way to tackling the destructive disease and would help ensure that Britain's stock of ash trees, and its countryside, remained resilient against pests and disease in the future.

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