SUMMER NUMBER 13 
Time: Actual Spraying, .... 102 min. 
. Including loading, ....120 min. 
ILE ooo, Gi veneio. (@)) PAS jorere INO WHR 1.50 
ANY Coste One apie labor oe ee ee $8.3! 
Ground Covered: 548 trees or 4.3 trees per minute at cost of $.015 per tree. 
Dusting Machine: Bean. Dust made in hopper of machine by adding 3 
pints of Black Leaf Forty to 50 lbs. of hydrated lime 
and allowing agitator to run for five minutes. 
Cost 
Mixture: Hydrated dime’ 100 vbs2e 4 ne eke ee eee er eee $1.10 
Blackybeat i orty, <6 opts ee eee eee 10.14 
(Ghosin. Kone any NI ee $11.24 
Time: 1 hour 30 minutes— 
Labor, '2.men @; $:25, per hour) 223.4 ss 
Total cost of dusting. 2. a= ae ee ee $11.99 
Ground Covered: 382 trees or 3.4 trees per minute at cost of $.036 per tree. 
A stop was made at each tree of from 5 to 10 seconds. There- 
fore more dust was used and less ground covered than in the 
commercial practice of never stopping and only throwing a cloud 
of dust over the tree. In this instance the tree was dusted from 
three sides. 
Similar experiments have been conducted in Lakeland, to 
which the writer added oil sprays, kerosene emulsion, soap solu- 
tion, and the follownig dusts: sulphur, calcium arsenate, com- 
binations of lime and sulphur, and calcium cyanide. 
The lowest percentage of kill was obtained from the sulphur 
dust, medium results were derived from oil, kerosene emulsion 
and soap emulsion, and the highest efficiency from the nicotine 
and the calcium cyanide dusts. However, the calcium cyanide 
was only effective when applied to the trees under tents, in which 
case a quarter of a pound was applied to four-year-old trees. 
The tree was left under the tent for a period of four minutes. 
This gave approximately a 100 percent kill. Some injury was 
done, however, to the tender foliage as a result of the burning 
caused by the dust. The nicotine dusts, which gave an average 
of 95 percent kill, were safer from the standpoint of the burning 
of the foliage, and had the added advantage of being less de- 
structive to the parasites than was the calcium cyanide. 
In our January issue, p. 41, we erroneously recorded Donald 
Reese as being present at the Cincinnati meetings. It should have 
been Chas. A. Reese. Mr. Reese, formerly of the State Plant 
Board, is now engaged in bee inspéction work for the State of 
Ohio with headquarters. at Columbus... Mr. Goodwin’s initials 
were also erroneous. They should have been U. C. 
