49 
peatedly to root cuttings. Even grafting has met with only mod- 
erate success. But this fall (1936) we found a happy solution 
of the difficulty, for we have at last succeeded in developing roots 
by the layering method. The details still have to be worked out, 
but the fact remains that asexual propagation by this method can 
be done. 
Disease Escape vs. Disease Resistance —Some people have said 
to us, “ How do you know your chestnut trees are not merely 
of being disease-resistant?’’? As we 
disease-escaping instead 
said in a former report, we are not trying to keep the disease 
away from our trees. The woods surrounding our five planta- 
tions are well supplied with diseased and dying shoots of the 
native chestnut, and the air surrounding the trees must be well 
laden with the fungus spores at least some of the time. Many 
of our hybrids have been killed by the bight. It is to be expected 
that some of them would inherit disease susceptibility. 
But to remove any doubt about the matter, and to put the whole 
subject of disease resistance on a definite, scientific basis, we inocu- 
ated,* in 1936, all those trees, not only hybrids but species as 
well, which were large enough to inoculate with the fungus. At 
— 
the same time, using the same culture of the fungus, we inoculated 
a large number of native shoots in the woods near the plantation 
for comparison. This work will be continued each year for at 
least three years, to see if the results of each year correspond. 
Finally, each individual will be given a number indicating the 
degree of its blight resistance. 
We have been told that we may lose all our trees as a result of 
these inoculations. There is nothing to fear on this score; for, in 
the first place, if they are easily killed, they are quite undesirable. 
In the second place, the inoculations have been made, in every 
case, well up from the trunk, on side branches. These branches 
can easily be removed, 1f for any reason that should be deemed 
— 
advisable. 
Management of the Plantations—In April, 1936, the National 
Research Council awarded us a grant-in-aid which enabled us to 
* The inoculations were made by removing a piece of bark about one inch 
long by % inch wide. The slit thus made (cut down as far as the wood) was 
filled with fungus mycelium and covered with electrician’s tape which was 
extended around the branch. The tape was removed a month later. 
