Ash dieback (Hymenoscyphus fraxineus) commonly known as Chalara is devastating Ash trees all over Europe and this has a major potential to disrupt so much in nature. This disease causes leaf loss, crown dieback and will eventually lead to the death of Ash trees. Serious research is being conducted into studying the genomes of Ash, to develop a breeding program of resistant trees. BBC Countryfile (21st February 2016) presented an article about tests done by adding Biochar to the soil around adult trees to halt the disease which proved to be a success.
We ourselves strongly recommend adding biochar when planting any trees as it offers many life long benefits including: retention of water, nutrients and minerals, reduced impact of pests and diseases, soil aeration and improved drainage. Biochar also adsorbs toxins from the soil and provides a home for vital microbes.