Chroust maďalový (Melolontha hippocastani F.) – hospodářský význam a možnosti eliminace škod v gradačním území LS Strážnice

The aim of this work was to evaluate the amount of damage caused by the grubs of forest cockchafer. The damage was assessed in relation to the habitat conditions of the mining and cultivation practices. The pilot plant treatment of Actara 25 WG and Force 1.5 G was evaluated for efficacy against 2nd and 3rd grub instars. A methodical design of aerial intervention to inhibit the forest cockchafer during the 2019 swarming was drawn up. When evaluating the amount of damage, 59,233 pieces of seedlings were checked in 2017. The pilot plant treatment was applied to 4 473 pieces of seedlings and the application was carried out in seven different variants on three districts of the Forestry Administration in Strážnice. The average amount of damage caused by the infestation of forest cockchafer grubs in the Forestry Administration in 2016–2018 is 36%. The Actara 25 WG applied by irrigation was evaluated as the most efficient variant during pilot plant treatment. Based on the vegetation inspection and the extent of the damaged area, an aerial intervention was proposed in two variants to inhibit the forest cockchafer swarming in 2019