Acer platanoides, USA, Maine, Franklin County © Bruce Watt, University of Maine, Bugwood.org

Acer paseudoplatanus, Flevoland, Reve-Abbertbos © Hans Jonkman

detail (underside)

conidiophores; from Bowen (1930a)

Acer pseudoplatanus, Dronten, Roggebotse Bos © Hans Jonkman (also a few Rhytisma acerinum spots)

heavy infestation

gall

characteristic are the conidiophores, actually propagules, with their bright white, ± 0.1 large heads, mainly at the underside of the spots.

host plants

Sapindaceae, etc.

Acer platanoides, pseudoplatanus; Aruncus dioicus; Carpinus betulus; Cornus sanguinea; Corylus avellana; Fagus sylvatica; Lonicera xylosteum; Prunus avium; Quercus robur; Tilia cordata.

Acer is the most important host by far.

references

Abras, Fassotte, Chandelier & Cavelier (2008a), Bowen (1930a), Ellis & Ellis (1997a), Kowalski & Bartnik (2008a), Kruse (2019a), Ludwig (1974a), Narumi-Saito, Hosoya, Sano & Harada (2006a).