chestnut blighta plant disease caused by the fungus
Cryphonectria parasitica (formerly known as Endothia
parasitica). It killed virtually all the native American
chestnuts (Castanea dentata) in the United States and Canada and
also is destructive in other countries. Other blight-susceptible
species include Spanish chestnut (C. sativa), post oak (Quercus
stellata), and live oak (Q. virginiana). In Europe several oak
species are affected.  Accidentally imported from the Orient,
the disease was first observed in 1904 in the New York
Zoological Gardens. By 1925 it had decimated the American
chestnut population in an area extending over 1,000 miles (1,600
km) north, south, and west of its entry point. Symptoms include
reddish brown bark patches that develop into sunken or swollen
and cracked cankers that kill twigs and limbs. Leaves on such
branches turn brown and wither but remain attached for months.
Gradually the entire tree dies. The fungus persists for years in
short-lived sprouts from old chestnut roots and