Hymenoscyphus fraxineus (T. Kowalski) Baral, Queloz, Hosoya

English n/a ISEIA: A3
Lëtzebuergesch n/a EASIN
Français n/a Wikipedia: Wikipedia - English - Hymenoscyphus pseudoalbidus Wikipedia - Français - Chalara fraxinea Wikipedia - Deutsch - Falsches Weißes Stängelbecherchen  Wikipedia - Nederlands - Chalara fraxinea
Deutsch Falsches Weißes Stängelbecherchen Wikispecies: n/a (2017)
Nederlands n/a Back to the list of neomyceta

Report the species

Report Hymenoscyphus fraxineus to the National Museum of Natural History.

Importance and distribution in Luxembourg

Distribution map of Hymenoscyphus fraxineus (T. Kowalski) Baral, Queloz, Hosoya in Luxembourg. Data source: Recorder-Lux & iNaturalist, 2019-09-21.

Hymenoschyphus fraxineus, Neudorf, Luxembourg. Photo par Guy Marson, June 2012.

Hymenoschyphus fraxineus, Neudorf, Luxembourg. Photo: Guy Marson, June 2012.

Hymenoscyphus fraxineus (Baral et al. 2014) is an ascomycete fungus that causes ash dieback, a chronic fungal disease of ash trees (Fraxinus excelsior) in Europe characterised by leaf loss and crown dieback in infected trees. It has been first described from Japan (Zhao et al. 2012).

Hymenoscyphus fraxineus is an invasive alien species coming from the Far East and greatly expanding through Central and Western Europe in recent years. Studies of herbarium material show that Hymenoscyphus fraxineus occurred already in 1978 in Central Europe (Queloz et al. 2011). It is now entrenched in Europe. It is closely related to a native fungus Hymenoscyphus albidus, which is saprotrophic and also grows on the petioles of dead leaves of ash trees.

Hymenoscyphus fraxineus, Park in Colmar-Berg, June 6th 2014. Picture by Christian Ries, June 6th 2014.

Crown dieback in ash tree infected by Hymenoscyphus fraxineus near Colmar-Berg. Photo: Christian Ries, June 6th 2014.

The species is first recorded on 16th June 2012 in Bois de Cessange (Municipality of Luxembourg) under its synonym Hymenoscyphus pseudoalbidus (Garnier-Delcourt et al. 2013: 35-36). It has already been reported since 2002 in Germany (Heydeck et al. 2005) and in 2010 in Belgium (Delhaye et al. 2010). The fungus is rapidly spreading throughout Luxembourg and in 2014 it is found in all regions of Luxembourg: a considerable amount of young ash trees are affected while only a part of the elder ash trees show dieback symptoms.

Risk assessment

ISEIA Protocol: B3 (3+3+3+1) = Watch List. First assessed 22 September 2017 by Christian Ries and Yves Krippel.


  • Baral H-O, V Queloz & T Hosoya (2014) Hymenoscyphus fraxineus, the correct scientific name for the fungus causing ash dieback in Europe. IMA Fungus 5(1): 79-80.
  • Garnier-Delcourt M, G Marson, Ch Reckinger, B Schultheis & M-T Tholl (2013) Notes mycologiques luxembourgeoises. VII. Bull. Soc. Nat. luxemb. 114: 35-54. (Pdf 6.5 MB)
  • Heydeck P, M Bemmann, H-G Kontzog (2005) Triebsterben an Gemeiner
    Esche (Fraxinus excelsior) im nordostdeutschen Tiefland. Forst und Holz 60: 505–506.
  • Queloz V, C R Grünig, R Berndt, T Kowalski, T N Sieber & O Holdenrieder (2011) Cryptic speciation in Hymenoscyphus albidus. For. Path. 41: 133–142, published online 30 March 2010 – doi:10.1111/j.1439-0329.2010.00645.x
  • Zhao Y-J, T Hosoya, H-O Baral, K Hosaka & M Kakishima (2012) Hymenoscyphus pseudoalbidus, the correct name for Lambertella albida reported from Japan. Mycotaxon 122: 25-41.

Suggested citation of this webpage

Ries, C. & M. Pfeiffenschneider (Eds.), 2019. Hymenoscyphus fraxineus (T. Kowalski) Baral, Queloz, Hosoya. In: neobiota.lu - Invasive Alien Species in Luxembourg. National Museum of Natural History, Luxembourg. URL: https://neobiota.lu/hymenoscyphus-fraxineus/ [Accessed 2019-09-21].

 Last updated on Friday, April 13, 2018.