Ash die-back: Could Dutch technique save Britain's trees?
A deadly fungus is threatening Britain's 80 million ash trees.
Dog walkers and ramblers have been asked to clean anything that has touched fallen leaves to stop the spread of ash die-back.
In the Netherlands, experts have pioneered new ways of preventing trees from becoming infected and have already had success with Dutch elms which were once threatened with extinction.
Anna Holligan reports from Amsterdam.