PLANS to bolster flood defences in York’s Museum Gardens may endanger one of the rarest trees in the country, experts have claimed.

The Environment Agency revealed last week that up to 15 trees near the historic Hospitium building might have to be felled when it raises and extends a flood embankment in the gardens to provide better protection for 48 local properties.

It said every effort would be made to limit the loss of trees in the final design, and rare and mature trees would be reinstated.

However, Peter Hogarth and Professor Ewan Anderson, who recently researched and wrote a history of the Museum Gardens, said one of the trees was an extremely rare ‘True Service Tree,’ or Sorbus domestica forma pyriformis, and every effort must be made to conserve it.

They said it had the status of ‘critically endangered’ within the Vascular Plant Red Data List for Great Britain and was on the Threatened Plants Database of the Botanical Society of the British Isles.

“It is consistent with the definition of a heritage tree: a large, individual tree with unique value, which is considered irreplaceable,” they said. “The main criteria are age, rarity and size, together with aesthetic, botanical, ecological and historical value.”

They said the Museum Gardens tree was estimated to be 90 or more years old, putting it within the time period when trees, propagated from the the original, were being distributed directly or via the Oxford Botanic Garden.

They added that apart from its obvious historical and botanical value, the tree was larger and better formed than a specimen in the Royal Botanic Gardens at Kew, and was a ‘very beautiful tree in its own right.’

Mr Hogarth claimed such well developed trees in Sheffield had been valued for their ‘human and ecological benefits’ at £37,000 each, and said he hoped a relatively minor modification to the plans would save the tree.

Vikki McCausland, of the agency, said: “We are aware of the importance of this tree and we are working with the York Museums Trust to ensure our work does not impact on it.”