SLU news

Plant breeding and climate uncertainty affects future forests

Published: 24 October 2022
The breeding work in Ekebo includes saving the ash by finding and propagating trees that are resistant to the ash dieback disease. Johan Kroon updated the participants about the work. Photo: Pär Fornling

Which tree species will grow best in future European forests and how can we develop forest stands resilient against pests, diseases and climate change effects? Those were some of the questions raised at the 50th anniversary and conference of Nordic Genetic Resource Centre’s forest section.

Across Europe forest researchers analyze how tree species will be affected by bark beetles, nematodes and other natural hazards due to rising temperatures, and how seedling production and planting can be adapted to the conditions of future forests. Researchers from the Nordic countries and Austria gathered in Lund to highlight and discuss how to develop the forest genetic resources to create resilient and productive stands for an uncertain future.

Magnus Löf, professor and head of the Southern Swedish Forest Research Centre, thinks the conference is important for both the forest research and industry.

“It is very important to conduct research on plant material and genetics of plants since changing climate will change growing conditions of our forests and trees. Tree species ranges may also change. Regeneration methods, tools and plant material may need to be adapted to new conditions”, says Magnus Löf.

Moving species and follow ups of seedlings

The benefits with assisted migration, which is the action of moving plants outside of its natural habitat to remove them from environments affected by climate change effects and other threats, were highlighted by Debojyoti Chakraborty from the Austrian Research Center for Forests/SUSTREE. The challenges with economic costs and invasiveness were, however, shown as some of the potential risks.

Henrik Hallingbäck presented the Planters guide (Plantval) developed by Skogforsk, which shows a production index in relation to the locally produced seedling material and can help forest owners in choosing the most beneficial plant for the specific area. He raised the challenge in predicting the most suitable seedling material today, since by the time the plants have reached mid-rotation there might be a different climate compared to when the seedlings were planted. Mattias Berglund, also working for Skogforsk, presented Föryngringskollen, aimed at reaching more stable regeneration results across Sweden with higher survival rates of planted seedlings.

Pest control, wood quality and mixed forests

The possibilities of improving birch wood quality through genetic selection was discussed via the presentation from Grace Jones and her dissertation from the Linnaues University, while Karin Hjelm from the Southern Swedish Forest Research Centre presented research on how to phase out insecticides but still effectively protect seedlings against pine weevil damage by using coatings.

Her colleague Magnus Löf presented one of the few ways through which forest owners can adapt to climate change – by restoring mixed species stands. Mixed forests are less stressed than monocultural stands, less affected by pests and can contribute to more long-term biodiversity. But increasing the amount of mixed forest stands in Sweden brings challenges.

“One main challenge for restoration of new mixed forests is the high current browsing pressure. As it is now, this leads to a homogenization of stand structures instead of a diversification. Another main challenge is the lack of practical knowledge on how to establish and manage mixed-species stands. Most recommendations are developed for monocultures”, says Magnus Löf.


Contact

Magnus Löf, Professor
Southern Swedish Forest Research Centre, SLU
Magnus.Lof@slu.se, +46 40 415119