338 
JOURNAL OF ECONOMIC ENTOMOLOGY 
[Vol. 13 
spray material must be placed there in the proper condition and in 
sufficient amounts to effect a coating as it falls. A coarse spray goes 
up in large droplets and comes down in much the same form. Unless 
a very excessive amount of spray material is thrown into the top of 
the trees only a few of the calyx ends will receive much spray and these 
will be decidedly spotted. 
In summarizing then, the successful use of the spray gun depends 
almost entirely upon the manner in which the spray is broken up. 
A pressure of 250 pounds on the large sprayers, i. e., the 10 horse power 
machines delivers a beautiful spray from two guns. This amount of 
pressure on a small outfit does not produce the same sort of spray. 
It takes at least 300 pounds with a 3J horse power outfit to approach 
this spray and then it is nowhere nearly as good. I am not suffi¬ 
ciently versed in mechanics to explain just why this difference occurs. 
Nevertheless there is a difference and anyone who will handle the deliv¬ 
ery from the small and large outfits can immediately feel the difference 
in the “life” of the spray. I am not conducting a propaganda for any 
one large type of sprayer, unfortunately at the present time there is 
only one on the market. Our other sprayer manufacturing companies 
must bring up their standards if they are to meet the demands of the 
orchardists for there will be a very great demand for these during 
the next few years. With the coming of increased facilities for proper 
spraying I firmly believe that we will see a marked improvement in our 
codling moth control and a yearly saving which will amount to many 
thousands of dollars. 
Summary 
The percentage of calyx entrants in apples is a very variable factor. 
In some seasons larger percentages enter than in others. There is 
much variation in different varieties of apples. 
The percentage of calyx entrants is not as great in the Northwest as 
one would be led to believe in reviewing the literature on the subject. 
Dust controls calyx worms. It can in no sense of the word be called 
a “driving application.” The material settles upon the locations 
needing protection and accomplishes* results if properly applied; this 
including calyx protection. 
Spray applied in finely broken up particles operates in exactly the 
same way whether applied with a rod or spray gun. 
The spray gun, in order to produce the proper type of spray cannot 
be used on inferior equipment. Two hundred and seventy-five 
pounds pressure with a 3j horse power sprayer produces a fair spray 
with two guns—an excellent spray with one gun. There is a very 
great need for higher powered sprayers with a liberal reserve. To be 
entirely effective the gun must be backed up with such equipment. 
