AbstractThe pathogenicity ofLeptographium terebrantisandLeptographium wageneri, was compared with that of eight isolates ofL. procerumfrom different parts of the world by wound inoculation of two‐year‐oldPinus strobusseedlings. Isolates ofL. procerumcaused limited discoloration around inoculation sites whereasL. terebrantiscaused girdling cankers andL. wagenerisystemically invaded seedlings. Only three of 160 seedlings inoculated with various isolates ofL. procerumdied;L. terebrantisandL. wagenerikilled 17 and 15 of 20 seedlings inoculated respectively. Inoculation ofL. procerumand controls caused localised discoloration around inoculation points and inoculation withL. terebrantisresulted in lesions up to 150 cm long on 15‐year‐oldP. strobus. Lesions associated withL. procerumwere however significantly longer than the discolored areas on control plants. In comparison withL. terebrantis,L. procerumappears to be a weak wound p