Origin: Far East, China

First finding in Slovenia: after the year 1980

Pathways: Spores of the fungus are spread by Elm bark beetles

Possible to identify: year-round

Habitat: Infects all Elm species (Ulmus spp.).

Status in Slovenia: A similar species, Ophiostoma ulmi is present in Slovenia since 1928. This species caused the first die-of of Elm trees. The second species, which currently predominates (O. novo-ulmi), spread to Slovenia after 1980. It caises massive die-ofs of Elm trees, but affects only mature trees. Younger trees remain unaffected, because bark-beetles do not affect them. The disease is occasionally found in all parts of Slovenia. 

Similar species: Similar symptoms are caused by fungi of the genus Verticillium (vrsti Verticillium alboatrum in V. dahliae).

Source:  Terenski priročnik za prepoznavanje tujerodnih vrst v gozdovih (Fieldguide for the identification of alien species in forests)

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