An Economic Comparison of Risk Handling Measures against Hylobius abietis and Heterobasidion annosum in the Landes de Gascogne Forest

- Key message : Phytosanitary risks are an increasing threat for forest, particularly due to climate change. Risk handling measures are effective economic strategies to manage such risks, so that Economics may provide relevant methodology to address this new challenge. - Context: Hylobius abietis and Heterobasidion annosum are two phytosanitary risks generating increasing damage in the Landes de Gascogne Forest. - Aims: We provide an economic comparison of different existing risk handling measures against Hylobius abietis and Heterobasidion annosum. - Methods: We use the Land Expectation Value, i.e. Faustmann criteria, to compare the different scenarios. - Results: We find that for Hylobius abietis, chemical treatment and fallow seem to be economically preferable to the absence of risk handling measure. For Heterobasidion annosum, we show that local stump removal is always preferable to total stump removal and chemical treatment. Local stump removal should be preferred to fallow when contamination occurs during the second thinning. Finally, our results indicate that fallow is always preferable to chemical treatment. - Conclusion: Beyond the specificities of the case study, the paper proposes a methodology to analyze such a problematic.