Chalara ash dieback could kill millions of ash trees in the U.K. Experts fear it could have the same devastating impact on the country’s woodlands and landscape as Dutch elm disease in the 1970s. But now, a study by tree and shrub care company Bartlett Tree Experts found that while a third of the established trees monitored have become infected with Chalara, none of the 20 trees which had enriched biochar applied to their roots were hit. This newly developed biochar combines a purified form of charcoal with fungi, seaweed and worm casts. It could help ash trees resist the Chalara disease.