 The two subspecies have now hybridized in Europe where their ranges have overlapped.The hypothesis that "O. novo-ulmi" arose from a hybrid of the original "O. ulmi" and another strain endemic to the Himalaya, "Ophiostoma himal-ulmi" is now discredited.There is no sign of the current pandemic waning, and no evidence of a susceptibility of the fungus to a disease of its own caused by d-factors