&6 
any pollen was shed. The young stamens were removed and the 
balance of the catkin, bearing its young pistils, was enclosed in a 
paper bag tied to the twig with copper wire. This step was 
necessary to prevent any of the pollen of the tree itself from 
reaching its own stigmas. For this and the succeeding operations 
itis a pleasure to acknowledge the valuable assistance of Miss Rusk, 
who has had considerable experience in this kind of work. The 
first pollination with American pollen received from Washington 
was carried out on June 28th. The bags were removed and the 
young pistils gently rubbed with the dehiscing anthers from the 
catkins, in order that some of the pollen might fall on the stigmas. 
One, or a part of one, of the catkins was tied near the pistils and 
the whole re-covered with the paper bag. Altogether, about 75 
pistils (or rather, pistil groups, since each involucre surrounds a 
cluster of pistils) were pollinated in this way. 
A second pollination was made on July 1, using the same pollen 
from Washington, which germination tests in the laboratory 
showed to be still viable. [lowever, for the Oyster Bay tree, 
pollen from a native shoot of chestnut then in flower near by was 
used. 
A third pollination was made on July 7. This time fresh pollen 
was used from Ohio, sent by the U. S. D. A., as well as pollen | 
myself obtained from native shoots in central New Jersey. At 
each pollination great care was taken to prevent pollen from the 
tree itself reaching the stigmas. On this account we used an 
umbrella, holding it closely over the bag during the operation, for 
during these summer days the air surrounding these chestnuts 1s 
plentifully charged with the pollen grains from the millions of 
dehiscing anthers.?. In one case, namely on the Oyster Bay tree, 
the third pollination, July 7, was omitted, because the air was so 
full of the Japanese pollen. 
The bags were left on as long as any of the flowers on the tree 
appeared to be shedding pollen. Several visits of inspection were 
made, and finally, on July 30, all of the stamens being evidently 
withered and brown, the bags were removed. Although only 
grocers’ ordinary paper bags had been used, they had kept intact 
2 This was absolutely necessary in the case of the Syosset tree, which has 
two leaders, each a different variety, one of them, at least, being grafted. 
It is interesting to note that this tree always bears heavy crops of nuts on 
both leaders. 
