 This disease was accidentally introduced into North America on imported Asiatic chestnut trees.Chestnut blight was first noticed on American chestnut trees in what was then the New York Zoological Park, now known as the Bronx Zoo, in the borough of The Bronx, New York City, in 1904, by chief forester Hermann Merkel.Merkel estimated that by 1906 blight had infected 98 percent of the chestnut trees in the borough.