Mr Blakey said the diseased trees were found during a routine inspection by the Department for Environment, Food and Rural Affairs (Defra) and ordered to be destroyed.

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It also said climbers must play a role in protecting the environment by avoiding wild bird nest sites and not slinging climbing ropes around trees.

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The 3km and 9km Circles in a Forest trails explore the refreshing green environment, passing 3m-high tree ferns, old-growth trees, strange fungi and babbling brooks.

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Forestry Commission (FC) Wales said the affected trees were small and "measures have been put in place to minimise the risk of the disease spreading to the wider environment".

BBC: Ash tree