Forests are exposed to a wide range of disturbances, including damage caused by insects, pathogenic agents and storms. Non-native organisms also alter various ecosystems. We investigate how illnesses affect trees and forests, how they can withstand such 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. Disease can cause symptoms in all parts of the tree, such as the roots (e.g. phytophthora), the bark (as is the case for bark beetles) or in the crown (ash dieback).
Trees weakened as a result of dryness, frost, poor light or nutrients are more susceptible to pests and diseases. Climate change is expected to increase infestation by harmful organisms. 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
In the group forest entomology we are also investigating the impact of climate change on bark beetle infestation. The bark beetle is a native pest, but has the potential to cause major damage.
We manage the 'Swiss Forest Protection' centre, which monitors pest and disease infestation in the forest as well as other damage such as browsing by game or environmental influences. We diagnose forest pests, advise forestry practitioners and authorities, survey forestry commission offices about forest damage, and hold training courses.
The group phytopathology conducts research into plant diseases. We use genetic and epidemiological methods to determine the causative organisms and investigate how they spread and infest their hosts. We also look for potential organic strategies to combat these organisms. Our research helps with risk analysis, diagnostics and controlling pathogenic agents
Our research focuses primarily on quarantine organisms, i.e., particularly dangerous organisms whose proliferation in Switzerland must be prevented at all costs. We are able to examine their behaviour and disease patterns under highly secure conditions in our plant protection laboratory. We also support the Swiss Federal Plant Protection Service.
Storms, forest fire, avalanches
Extreme events such as storms, forest fires, droughts or avalanches can cause damage to larger forest areas. We investigate the significance of these events on forest development. We perform a range of experiments, e.g. to test how resistant certain types of trees are to arid conditions and how long repopulation takes after a forest fire. More extreme events of this kind are expected as climate change continues its rapid advance. In the light of rising demand for wood, the significance of such disturbances will increase.