Evaluation of Damage to Forest Tree Plantations by Wild Boar in the Czech Republic

Wild boar (Sus scrofa) populations in Central Europe have been growing longterm, and damages to crops and forests where boars damage freshly planted tree seedlings are growing too. In addition to having a significant economic impact, these damages worsen the prospect of successful restoration of bare land. This study presents an analysis of damage to tree seedling plantations caused by wild boar in the Czech Republic. We used data from an extensive questionnaire survey among forest owners, our own survey of the extent of damage in model areas, and experiments in locations with a large boar population. Damage to plantings is a widespread phenomenon, and up to 80% of planted trees may be damaged in heavily affected locations. The wild boar does not differentiate between bareroot or containerized seedlings or tree species. Trees were often simply pulled out, without any traces of damage to the root system. Wild boar preferences were not affected by the composition of the substrate of containerized seedlings. Seedlings were damaged most often during the 4 weeks after planting; after this period, the risk of damage fell considerably. Based on the obtained data, we estimated that the damage caused by wild boar rooting out seedlings in 2019 throughout the Czech Republic amounted to $3,199,200 USD, which is equivalent to $122 USD per km2 of forest land. As we are not currently aware of any method of protection against this damage, the most expedient solution seems to be the reduction of the wild boar population, as well as to monitor and protect freshly established cultures, for a period of at least 4 weeks after planting.