Forest and Tree Pests

Plant pests pose a growing threat to forests and other wooded land. Plant trade is increasingly global, heightening the risk of inadvertently introducing exotic organisms. At the same time, climate change is shifting biotic disturbance patterns as it often affects pathogens and their hosts in different ways. In the last decades, the EU has confronted several large-scale outbreaks of new tree pests that can affect forests, and other tree-dominated landscapes, throughout the EU territory. We seek insights into these epidemics to inform the actions to control or mitigate them.

With partners, we have researched process-based pest spread models, that simulate a tree pest epidemic based on the characteristics and behaviour of the pathogen, its hosts, and its vectors (e.g. De la Fuente et al. 2018). However, when new pests are first found, very little is typically known about their ecology. Even basic facts, such as the complete list of potential host plant and vectors, let alone their precise role in the pest spread, usually takes considerable time to compile. As a result, traditional pest spread models can often not be reliably developed for quarantine pests. Therefore, we also investigate new analytical approaches that can shed light on plant pest dynamics, even when epidemiological parameter are highly uncertain (e.g. Strona et al. 2016).

We use remote sensing to monitor tree health, particularly in the context of pests. The early detection of new infections is key to containing epidemics. Therefore, we research how the early stages of plant stress, that might be caused by pests, can be spotted in Earth Observation data, be it from satellite or the air (e.g. Zarco et al 2018a, 2018b). For plant pests that are affecting large areas, we additionally research methods to map the extent and progression of the damage they cause.


Zarco-Tejada, P. J., C. Camino, P. S. A. Beck, R. Calderon, A. Hornero, R. Hernandez-Clemente, T. Kattenborn, M. Montes-Borrego, L. Susca, M. Morelli, V. Gonzalez-Dugo, P. R. J. North, B. B. Landa, D. Boscia, M. Saponari, J. A. Navas-Cortes. 2018a. Pre-visual Xylella fastidiosa infection revealed in plant-trait alterations. Nature Plants, 4, 432-439. doi:10.1038/s41477-018-0189-7

Zarco-Tejada, P. J., A. Hornero, R. Hernandez-Clemente, P. S. A. Beck. Understanding the temporal dimension of the red edge spectral region for forest decline detection using high-resolution hyperspectral and Sentinel-2a imagery. 2018b. ISPRS Journal of Photogrammetry and Remote Sensing, 137, 134-148, doi:10.1016/j.isprsjprs.2018.01.017

de la Fuente, B.. S. Saura, P. S. A. Beck. Predicting the spread of an invasive tree pest: the pine wood nematode in Southern Europe. 2018. Journal of Applied Ecology, 55(5), 2374-2385 doi:10.1111/1365-2664.13177

Strona, G., C. J. Carstens, P. S. A. Beck, B. A. Han. 2018. The intrinsic vulnerability of networks to epidemics. Ecological Modelling, 383, 91-97 doi: 10.1016/j.ecolmodel.2018.05.013

Strona, G., C. J. Carstens, P. S. A. Beck. 2017. Network analysis reveals why Xylella fastidiosa will persist in Europe. Scientific Reports, 71(7) doi: 10.1038/s41598-017-00077-z

Contact: pieter.beck[at]


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