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Forest under pressure: Diseases, pests and disturbances

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Climate change, but also disturbances such as insect infestations, pathogens or storms are putting pressure on our forests. Non-native organisms also alter various ecosystems. We investigate how illnesses affect trees and forests, how they can withstand disturbances and how well they recover afterwards.


Fungi and – in rarer cases – bacteria, nematodes, phytoplasms or viruses along with a huge variety of insects infest and cause harm to trees. Climate change is expected to increase these infestations. A warmer climate will also favour the survival of non-native pests, which trees are less well-equipped to combat than native pests.

Monitoring forest health

Our research groups Phytopathology, Forest Entomology and Forest Protection Switzerland are at work for forest health. We determine harmful organisms such as insects and fungi, investigate how they spread, how they attack their hosts or how they can be biologically controlled. Our main focus is on quarantine organisms whose spread in Switzerland must be prevented at all costs. We can examine these under high-security conditions in our plant protection laboratory.  We offer diagnostics of pathogens as well as advice and further training for forestry professionals.

Storms, forest fires, avalanches

Extreme events such as storms, forest fires, droughts and avalanches can severely impair forest services such as a protection against natural hazards or timber production. They are expected to increase under rapidly advancing climate change. We investigate their effects on the forest, its function and development, and advise forestry practice.



Forest Protection Switzerland (WSS)

We diagnose the causes of forest damage, provide information on current events and advise those affected on forest protection issues.

Invasive species

We help to foster an understanding of the biology of these problematic species, and to prevent or curb their spread.


This website (in German and French) models the daily development of bark beetle populations in Switzerland, including their initial flights.

Plant protection lab

In the high-security laboratory, harmful organisms for trees and shrubs can be safely diagnosed and used for experiments.

Consequences of forest fires

Forest fire destroys animals and plants and reduces protection against natural hazards. We investigate how biodiversity and the protective function...

Swiss Federal Plant Protection Service

WSL supports the SPPS in risk analyses, in the development of control strategies and in the area monitoring of new harmful organisms.