Movement in Trade
It is apparent that several host-specialized forms of the fungus have been introduced into many regions. Propagative materials, especially cuttings, are a likely source. Packaging material and dunnage are also likely means of dispersal of the fungus. The Platanus form may have been introduced on packing material to Europe from North America during World War II Panconesi, 1981, 1999) and has caused substantial damage to ornamental Platanus in southern Europe. This form can survive in Platanus wood taken from diseased trees (Grosclaude et al., 1995), which may be an efficient means of introducing the pathogen to new locations.