When we think about Sweden, we don’t think about drought conditions but forests in southern Sweden are suffering from recurring droughts, something that accelerated with the dry summer of 2018. Source: Timberbiz
The trees have not yet recovered and are having difficulty starting to grow in several places. This was shown by this year’s forest damage report for 2024 from the Swedish Forest Agency.
“There are forests that are still standing and stomping and do not want to start growing properly again after the drought and are therefore also more susceptible to damage. This is worrying for the growth in the forest,” said Lennart Svensson, forestry specialist and national forest damage coordinator at the Swedish Forest Agency.
Even though 2024 was not a drought year, drought effects are still visible in the forest, which in all likelihood accelerated in connection with the warm and dry summer of 2018.
Growth in Sweden’s forests has decreased over the past 10 years. Drought is considered to be the main and most likely explanation for the decrease in growth.
The effects are most evident in the southern parts of the country, where Gotland and Kronoberg appear to be the worst affected according to observations made by the Swedish Forest Agency.
On Gotland, extensive growth reduction and pine death in planted pine stands were noted in 2024. The pines are losing needles, showing signs of stress with yellowing needles and thinned crowns. The trees are at risk of dying prematurely.
The drought in combination with fungal attacks is also considered to have been a triggering factor for the damage to birch in the form of significant bud and branch death that has been observed primarily in Kronoberg County.
More injury trends and outbreaks across the country are also noted in this year’s report:
- A relatively severe outbreak of pine weevil was observed on Gotska sandön, where the distribution area was approximately 460 hectares. A rough estimate is that the mortality rate among the pines is between 5% and 15%.
- The bark beetle is the insect that is believed to cause the most damage to conifer plantations when it gnaws at the bark. Most reports come from Götaland, where the damage is estimated to be more common than before.
- The fungus Törskate, which attacks and damages pine trees, continues to be a concern in northern Sweden. Damage levels are still considered high in large parts of the region.
- Elm disease continues to spread in the country and 2024 seems to be a particularly aggressive year. Notes about infected and dead elms come from almost all counties in Götaland and Svealand. On Gotland, an inventory shows a sharp increase.
- Grazing damage to pine trees by moose and other deer continues to be a major problem. This year’s moose grazing inventory (Äbin) shows that 12% of pine trees in young forests (1–4 m high) have annual damage. This is more than double the society’s target of a maximum of five percent.
“The best way to combat damage to the forest is to invest in the right trees on the right land so that they become strong and resilient. We also know that having a varied forest with different tree species and ages is effective in resisting storms and attacks from insects and fungi,” Mr Svensson said.
