Hymenoscyphus fraxineus (T. Kowalski, Baral, Queloz & Hosoya)
Significance: Hymenoscyphus fraxineus, causal agent of ash dieback, infects Fraxinus spp. (ash) trees. Trees exhibit shoot and leaf wilting, leaf drop, bark necrosis, and dieback (Milenkovi? et al, 2017). Ash dieback has been reported in Europe from Austria, Belgium, Croatia, Czech Republic, Denmark, Estonia, Finland, France, Germany, Guernsey, Hungary, Ireland, Italy, Latvia, Lithuania, Luxembourg, Netherlands, Norway, Poland, Romania, Russia, Slovakia, Slovenia, Sweden, Switzerland, UK, and Ukraine (EPPO, 2017). It has been reported in Asia from China, Japan, and the Republic of Korea (EPPO, 2017).
Ash dieback caused by Hymenoscyphus fraxineus has been highlighted in previous NAPPO-PAS Pest Alerts under the synonym Chalara fraxinea(http://www.pestalert.org/viewNewsAlert.cfm?naid=26&keyword=Chalara%20fraxinea; http://www.pestalert.org/viewNewsAlert.cfm?naid=69&keyword=Chalara%20fraxinea; http://www.pestalert.org/viewNewsAlert.cfm?naid=86&keyword=Chalara%20fraxinea; http://www.pestalert.org/viewNewsAlert.cfm?naid=89&keyword=Chalara%20fraxinea).
Issues of Concern: In 2015, Fraxinus excelsior (European ash) and F. angustifolia (narrow-leaf ash) trees in Serbia (Ke?a et al., 2017) and in August of 2016, F. excelsior trees in Montenegro (Milenkovi? et al., 2017) were all exhibiting symptoms of ash dieback. These are the first reports of H. fraxineus in Montenegro and Serbia.
EPPO (2017) PQR - EPPO database on quarantine pests (available online). http://www.eppo.int
Ke?a, N., T. Kirisits, and A. Menkis. 2017. First report of the invasive ash dieback pathogen Hymenoscyphus fraxineus on Fraxinus excelsior and F. angustifolia in Serbia. Baltic Forestry 23(1):56-59.
Milenkovi?, I., T. Jung, Z. Stanivukovi?, and D. Karadži?. 2017. First report of Hymenoscyphus fraxineus on Fraxinus excelsior in Montenegro. Forest Pathology DOI: 10.1111/efp.12359.