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the box fumigators over any tree varying in height up to 17 feet. The 
system worked perfectly, and we were pleased beyond our expectation. 
We applied it to a block of infested pear trees the first and second 
weeks in April this spring. 
It requires three or four men to operate an outfit of this kind, the 
help, of course, depending upon the number of fumigators in use. It 
requires one man to look after the chemicals and time, and two or three 
to handle the fumigators and rigging. With an equipment of ten 
fumigators this force under favorable conditions could in one day fumi- 
gate from 175 to 200 trees from 12 to 17 feet in height. 
The cost of the chemicals is about 4 cents for the 8-foot box without 
the hood extended; 5 to 6 cents when the hood is half extended; 6 to 
7 cents fully extended. The cost of whale-oil soap for spraying trees 
would be from a third to a half more, while 30 to 50 per cent kerosene 
would about equal the cost of the chemicals for gas. 
The cost of the large fumigator complete is about $12, or just two- 
thirds that of a 25-foot sheet tent sufficient for covering a tree the same 
size. The rigging for handling the fumigators costs about $12. Tak- 
ing it all in all, this system is simple and can be used by the average , 
orchardist. 
In reporting this method for handling hydrocyanie acid gas, I desire 
to say that I have had the practical experience of my friend, Capt. Rh. 
S. Emory, of Chestertown, Md., without which it would not have been 
possible for me to have completed these experiments. The equipment 
was furnished me by the State horticultural department and the 
experiment station, but the mechanical details were under the personal 
supervision of Mr. Emory. I desire to name this the ‘“‘ Emory fumiga- 
tor,” therefore, in his honor, as a slight recognition of his services and 
practical experience. 
Mr. Webster inquired as to the possibility of securing the entire 
extermination of the scale in an orchard. 
Mr. Johnson stated that such an attempt was impractical in large 
orchards, but that the scale could be controlled by fumigating a part 
even of the trees in alternate years in cases where it would be impos- 
sible to treat an entire orchard in a single season. 
Mr. Webster recalled fumigating a quantity of infested stock which 
was wet and partly covered with mud at the time of treatment, yet all 
the scales were killed. 
Mr. Johnson’s experience in treating wet nursery stock was contra- 
dictory to that of Mr. Webster, and he had thought the failure of the 
process to be due to the afiinity of hydrocyanic acid gas for water. 
Mr. Marlatt called attention to the great value of Mr. Johnson’s work 
in developing a practical method of fumigating orchard trees. The 
problem at the outset was surrounded by many difficulties, but Mr. 
Johnson had boldly attacked it and reached a satisfactory solution. 
