First report of Chalara fraxinea in the Netherlands
Since 2008, specific surveillance of ash trees (Fraxinus spp.) has been conducted in the Netherlands to detect the possible presence of Chalara fraxinea (EPPO Alert List). In August 2010, the Dutch NPPO reported the first occurrence of this fungus on its territory. C. fraxinea was detected (isolation on agar media, PCR) on Fraxinus trees in the north-eastern part of the country in a public green area. No forests are located in the vicinity of the finding. The infected ash trees were planted in 1975 but their origin is not known. Because C. fraxinea occurs in many European countries, it is suspected that natural spread is responsible for the disease introduction into the Netherlands. An additional survey will be conducted to determine the distribution of the disease in the area concerned. Considering the already wide distribution of C. fraxinea in Europe, no measures were taken on infected trees.
The pest status of Chalara fraxinea in the Netherlands is officially declared as: Present, only in some areas.
NPPO of the Netherlands (2010-08).