Several birds are important as agents of dissemination of plant pathogens.
Though comparatively small in number, bird vectors of plant disease may have a great impact. For example, endothia parasitica, the fungus which causes Chestnut Canker, produces sticky spores which adhere to the feet of birds. These birds carry the spores over considerable distances: in fact, they made it impossible to eradicate the fungus after it had been accidentally introduced into the eastern USA from the Orient.