Situation of Dryocosmus kuriphilus in Croatia
Dryocosmus kuriphilus (Hymenoptera: Cynipidae – EPPO A2 List) was found for the first time in Croatia in 2010 during a specific survey programme (EPPO RS 2011/193). The first infested chestnut (Castanea sativa) trees were detected in May 2010 in one forest in Lovran (Primorsko-goranska county), and then in June 2010 at several other localities in the City of Zagreb, Samobor (Zagrebačka county), Ozalj (Karlovačka county), Stubičko podgorje and Hum na Sutli (Krapinsko-zagorska county). According to the number of galls per shoot observed during the survey, it can be estimated that in the localities of Lovran, Samobor and Ozalj (single galls per leaf/shoot) D. kuriphilus has been recently introduced. However, the localities in Zagreb (Zagrebačka gora, Bundek, Grmoščica, Gornje Prekrižje) had high infestation rates (numerous galls per leaf/shoot), therefore it can be estimated that for these locations D. kuriphilus has been present since 2007 or 2008.
Subsequently, visual inspections of chestnut seedlings revealed the presence of the pest in one fruit nursery in the locality of Čremušnica (Gvozd, Sisačko-moslavačka county). Laboratory analyses showed the presence of D. kuriphilus larvae in galls on two C. sativa seedlings that had been produced and imported from a nursery in Slovenia. Phytosanitary measures were taken immediately and the two infested seedlings were uprooted and destroyed, before the adults could emerge from the galls. Demarcated zones (infested zone + focus zone of 5 km radius + buffer zone of 10 km radius) have been established in the infested forest areas.
The pest status of Dryocosmus kuriphilus in Croatia is officially declared as: Present, first found in 2010 in 12 localities, under official control.
Sources
NPPO of Croatia (2011-11).