59 
showed very clearly that the roots of the chestnut are much 
more resistant than the shoots to the attacks of the fungus. 
In roots and shoots of approximately the same diameter and 
from the same tree, inoculated with a pure culture of the fungus 
(Endothia parasitica), the growth of the parasite was only slight 
in the root tissue, but girdled the shoots in all cases. This 
greater resistance of the roots is probably due, in part at least, 
to the fact that the root bark contains a much greater amount of 
tannin than the bark of the shoots and trunk. Recent investi- 
gations of the Leather and Paper Laboratory of the Bureau of 
Chemistry, U.S. D.A., have shown that in the samples analyzed 
the tannin content of the root bark was more than twice that of 
the trunk. It is this greater resistance of the roots, therefore, 
which is making it possible for basal shoots to develop. Usually 
they soon die off from the disease, but occasionally they become 
old enough and large enough to bear nuts. This last fact is of 
tremendous significance in that it will surely enable the tree to 
postpone still further off into the future its possible extinction. 
The production of seeds will provide for young trees, and there is 
always the possibility that some of these will be found still more 
resistant. These nuts should by all means be carefully gathered 
and planted. About 100 nuts obtained from such chestnut 
shoots by boy scouts last fall in Northern New Jersey and a 
large number which were secured from still vigorous trees at 
the outer limits of the chestnut range near Portland, Maine, 
are being planted out on land owned by the writer near Hamden, 
Connecticut, in the hope of breeding more resistant strains from 
this and other stock. 
2. Nectria Canker on Paper Birch—In experimental work 
which is being carried on at Brooklin, Maine, on the Nectria 
canker of the birch, the susceptibility of the paper birch (Betula 
alba L. var. papyrifera (Marsh.) Spach. was demonstrated this 
year. Inoculations in paper birch had been made in 1924, the 
inoculum having been taken from trees of yellow birch (Betula 
lutea) affected with this disease. None of the white-barked species 
had been previously affected, but as a result of the inoculations 
from the yellow-barked species, this year small cankers have 
been found, in which typical perithecia of Creonectria coccinea 
had developed. This fungus has therefore been found by the 
