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It has been found that basal shoots develop from trees killed 
to the base by the blight. Experimental work has proved beyond 
a doubt that the roots and root collar are more resistant to the 
fungus than the trunk. 
It has been found that many basal shoots live long enough to 
bear nuts and thus will reproduce the species. 
Plans: 
1. To continue the search for resistant stock. 
2. By cross breeding the more resistant stock already found 
with resistant Japanese or Chinese species to develop a strain to 
replace the American chestnut. (The Japanese and Chinese chest- 
nuts are not good timber trees. It should be possible to combine 
the greater resistance of the Chinese and Japanese species with the 
timber qualities of the American chestnut. 
3. To grow young trees of American chestnut, and to determine 
whether environmental conditions affect the quality of resistance. 
4. To determine experimentally the cause of resistance. 
ProBLEM 2. THE NEcTRIA CANKER OF THE BIRCH 
Scope: 
To work out in detail the life-history of the fungus causing the 
Nectria Canker of the Birch (Betula), to determine the amount 
of damage it causes in the Birch and develop methods for its 
control. 
Status: 
By inoculations made in Connecticut and Maine in 1918 and 
1924, respectively, the parasitic nature of the fungus has been 
proved, and the belief that it is the immediate cause of the canker 
has been confirmed. It has been found further that the growth 
of the parasite is slow, and there is abundant evidence at hand te 
prove that it grows in the wood as well as in the living bark. 
gona 
. By laboratory studies to work out the morphology of the 
eee 
2. To determine the way in which the disease is carried to 
healthy individuals. 
o determine the rate of growth of the fungus in the host. 
