Mapping of Heterobasidion root and butt rot risk in Finland and precision prevention of Heterobasidion at the forest stand level

Heterobasidion spp. are root decay fungi, and they decrease the growth of forests and their ability to sequester carbon dioxide. As a result, the fungus causes massive losses in the forest industry and weakens the efficiency of forests in mitigating climate change. Forests infected with Heterobasidion are also more prone to other forest disturbances. Heterobasidion fungi benefit from climate change, as increasing temperatures, a longer growth season, and rainy winters support its spread and viability.

The fungi have spread widely over Finland, and therefore eradication and prevention against Heterobasidion must be boosted promptly. In addition to treating infected stands, its spread to new stands should be prevented. Stump treatment to stop the fungus from spreading is not economically profitable in the worst-infected areas, and this approach cannot eliminate the pathogen once it has penetrated the root network of the trees. Currently, the only way to contain the fungi in such forest stands is to change the tree species, and it also incurs economic costs for the forest owner. Therefore, better information is needed for the identification of the risk areas, and the better design of eradication and prevention measures against the fungi within stands. The data created by harvester machines in forest operations could be used to plan cost-efficient prevention measures and to produce up-to-date information on the spread of these fungi across Finland.

The aim of this project is to leverage harvester data and open geographic data to develop a new method for precise and targeted prevention of Heterobasidion on the stand level as well as to produce precise information on the spread of the pathogen in Finland. The results of the project will be deployed into practice, and they support both the adaption of the forestry sector to climate change as well as the development of climate change mitigation measures.

The project is part of the Catch the carbon climate measures initiated by the Ministry of Agriculture and Forestry in the spring of 2020, which aim to reduce the greenhouse gas emissions from forestry, agriculture, and other land use and to strengthen carbon sinks and storages. Luke implements the project in collaboration with Metsäteho Oy and Suomen metsäkeskus.