branch quickly girdled and killed. (no resistance)— 
Red Label 
As a result of our two years of inoculations we find that, in 
general, the results correspond. One more year’s work will 
finish the testing for the larger trees; many younger ones will 
soon be old enough to inoculate. In 1936 the inoculations were 
made during the end of July and the first part of August; this 
year about two weeks earlier. 
After two years’ testing, we find that the Japanese-American 
hybrids on the whole are susceptible to the disease, with a few 
In two cases these hybrids have so far shown ab- 
exceptions. 
Two trees of our Chinese species (C. mollts- 
solute resistance. 
sima) have also shown absolute resistance and one tree of our 
Japanese species (C. crenata). In general, the Chinese are the 
most resistant of all the trees, with the Japanese considerably 
behind. One of the Folk Japanese has proved 100% resistant 
to the inoculations, but the ‘‘ Folks”’ are very variable: some are 
fairly susceptible. The Spanish chestnuts (C. sativa) are very 
low in resistance. The Americans (C. dentata), as far as we have 
tested them, are the poorest of all; and, as a matter of fact, 
several of our young Americans died last year as a result of these 
inoculations. 
Cutting out the Blight.—Since we wish to save some of our 
Japanese-American hybrids for further breeding (on account of 
such desirable characters as rapid growth rate and erect habit) 
I have been cutting out any diseased spots in the bark; and I 
have found that healing occurs, and, so far at least, the disease 
has not reappeared.* This is a very difficult operation to perform 
successfully on American chestnut. 
Grafting—We grafted our best Japanese-American hybrid 
(H86—-31) on pure Japanese stock with the result shown in Fig. 3 
Scions of Chinese chestnut were also successfully grafted on 
Quercus montana, the Chestnut Oak, and on Quercus velutina and 
C. coccinea, the Black and Scarlet Oaks. The graft on the Black 
Oak lived only until September, however. 
* Likewise, Gravatt (Farmers’ Bull. 1641, ‘‘Chestnut Blight,” p. 17. 
U.S.D.A. 1930) says that ‘‘most of the oriental trees can be saved by system- 
atically cutting out any cankers that may appear and then painting the 
wounds, 
