The chestnut blight fungus, Cryphonectria parasitica, was accidentally imported on plant material in the late 19th Century and first identified as a new pathogen in New York City in 1904. The blight–an Asian fungus to which our native chestnuts have very little resistance–spread quickly. By 1950, the foundation species that was once found across 180 million acres of eastern forests had disappeared, except for the shrubby root sprouts the species characteristically produces.