An economic comparison of strategies forest pathogens

In this paper, we use a cost-benefit approach in order to compare existing treatments to prevent the invasion of three pathogens (Hylobius abietis, Dothistroma septospora and Dothistroma pini, Heterobasibion annosum) in Landes forest, in the South-West of France. Our results show that for Hylobius abietis, the prevention, either self-insurance (cypermethrin solution) or self-protection (fallow), appears to economically dominates the absence of prevention. For Dothistroma septospora and Dothistroma pini our results indicate that the treatment analysed, (mancozeb solution), is never economically relevant for the forest owner as it induces negative LEV. We compute the threshold value of the treatment for which the LEV becomes positive and thus the treatement could be considered. This value is 45% lower than the current one. Finally, for Heterobasibion annosum, we analyse various self-protection activities and we show that a local stump removal just after contamination is always more profitable than a systematic preventive treatment and that a fallow at the end of rotation better performs local stump removal if and only if the contamination occurs during the second thinning, when the forest is mature. Beyond the specifities of the case study, the paper proposes a methodology to analyse such problematic.