Black Tar Spot

Rhytisma acerinum

''Rhytisma acerinum'' is a plant pathogen that commonly affects sycamores and maples in late summer and autumn, causing tar spot. Tar spot does not usually have an adverse effect on the trees' long-term health. ''R. acerinum'' is an Ascomycete fungus that locally infects the leaves of trees and is a biotrophic parasite. The disease is cosmetic and is therefore usually controlled only with sanitation methods.
Tar Spot - Rhytisma acerinum Host: Maple leaf; mixed forest https://www.jungledragon.com/image/116182/tar_spot_-_rhytisma_acerinum.html https://www.jungledragon.com/image/116184/tar_spot_-_rhytisma_acerinum.html https://www.jungledragon.com/image/116183/tar_spot_underside_-_rhytisma_acerinum.html Acer,Fall,Geotagged,Rhytisma,Rhytisma acerinum,United States,biotrophic parasite,fungus,maple tar spot,plant pathogen,tar spot

Naming

''Rhytisma acerinum'' can occur in many tree species, with the most commonly affected genus being ''Acer''. The species most commonly affected by the disease are Norway maple, silver maple, and sycamore maple.

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Taxonomy
KingdomFungi
DivisionAscomycota
ClassLeotiomycetes
OrderRhytismatales
FamilyRhytismataceae
GenusRhytisma
SpeciesR. acerinum
Photographed in
United States of America