June, ’23 
HOUSER: DUSTING TALL TREES 
249 
but after seeing with what unbelievable dispatch an area could be 
covered and with what neatness and thoroughness the treatment could 
be made, without exception they have become thoroughly converted to 
the idea. 
The next paper will be presented by Mr. A. F. Burgess. 
EXPERIMENTS IN DUSTING FOREST AREAS WITH AN 
AIRPLANE 
By A. F. Burgess, Melrose Highlands , Mass . 
(Paper withdrawn from publication) 
Mr. W. E. Britton: I would like to ask if the gipsy moth caterpillars 
were killed by this method of dusting and whether the experiments will 
be continued. 
Mr. A. F. Burgess: Owing to delay in securing the machine and the 
equipment, and the bad weather, the dust was applied rather late in the 
season, and the results showed no effective killing of gipsy moth cater¬ 
pillars. Data secured was mainly on the distribution of the poison and 
the general utility of this method of work. At present I do not think 
it is a practical method in large forest areas. It is possible that the 
use of a dirigible or a very slow moving machine might be more effective, 
but the operation of an airplane in large forest areas is simply mechanical 
and lacks the element of thoroughness that you should have if you are 
going to do effective work. 
Mr. J. M. Swaine: We hope to persuade our Air Service to carry on 
one or two experiments on a large scale next summer in Western Canada. 
It seems to me from all I can learn and the experience I have had in the 
Air Survey work, that the heavier than air machine is altogether too 
risky for large operations. How high were you flying? 
Mr. A. F. Burgess: 50 to 100 feet above the tree tops and the 
nearest landing place was 12 miles away. 
Mr. J. M. Swaine: We cannot get pilots from our Air Service to 
fly under such conditions. They will not take the chances. There is 
great danger and if your engine fails, a serious accident will result. 
Flying a few feet above the tree tops is altogether too risky. With a 
lighter than air machine you can fly more slowly and the work might be 
