Butternut (Juglans cinerea) decline question.

Starr Cash starr at starrcash.com
Fri Jan 21 10:00:07 EST 2000


Copied following from Ency. Britannica on-line.  Looks like the
chestnut fungus does affect some oaks.

chestnut blight 

 a plant disease caused by the fungus Endothia parasitica. It has
killed virtually all native American chestnuts (Castanea dentata) in
the United States and Canada and is also destructive in other
countries. Other blight-susceptible species include Spanish chestnut
(C. stavia), 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 in less susceptible hosts. It is spread
locally by splashing rain, wind, and insects; over long distances, by
birds. Chinese (C. mollissima) and Japanese (C. crenata) chestnuts are
resistant. Crosses between American and Asian species have produced
varieties with excellent nuts, but timber quality is closely linked
with blight susceptibility. In the 1970s a native American strain of
chestnut blight was identified. Experiments indicated that the native
strain was less virulent than other strains and that it had a
nullifying effect on lethal strains. Unfortunately, the mild strain of
blight does not readily spread from tree to tree among American
chestnuts.




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