Healing instead of cutting down

Trees can also get sick. In urban areas, this usually means that the infested tree has to be felled for safety reasons. Empa researcher Francis Schwarze is familiar with wood and fungal pathogens and has developed methods to assess trees without damaging procedures and, if necessary, to heal them with selected antagonists. He has now published his knowledge on this topic in a new book. If a tree is attacked by wood-decomposing fungi, the wood inside the tree is decomposed over a period of many years until in the worst case it falls down. If this happens in the forest, it's usually not a big deal - but it can have devastating effects in urban areas. For this reason, municipal offices are obliged to carry out annual visual inspections on their trees. If there is a well-founded suspicion of damage - for example, if so-called fungal fruiting bodies are recognizable - an expert examination is necessary. For these analyses, however, diagnostic methods are often used that injure the tree (e.g. drill resistance and sound velocity measurements or a drill core removal). The expert can then measure the extent of wood decomposition. In many cases, however, the wounds caused represent entry points for further fungal infections. Or the fungus can spread faster (from an infested tree). A fig tree infected by Phellinus noxius in Hong Kong before treatment with Trichoderma harzianum T-TMS1: Two weeks after treatment with Trichoderma harzianum T-TMS1, numerous adventitious roots (arrows) had already formed. Cure is possible with early detection