MISCELLANEOUS INSECTK'IDK I X VKSTIOATIONS. 
31 
certain advantages. The principal points given in favor of the 
powder over the paste are that it can be more conveniently mixed, 
that the proper amount to be used for each spray tank may be 
weighed out with a greater degree of accuracy, and that it can be 
stored more readily without deterioration. There is also a distinct 
saving in freight. For the advantages enumerated the fruit grower 
is asked to pay a trifle more in price, since it costs the manufacturer 
somewhat more to produce the powdered form. 
With this in view, experiments were conducted to test the efficiency 
of the powdered form in comparison with the paste. Since the 
powdered arsenical has approximately twice the strength of the paste, 
one-fourth pound of the powder was directly compared with one-half 
pound of the paste, one-half pound of the powder was compared with 
1 pound of the paste, and 1 pound of the powder was compared with 
2 pounds of .the paste. All of these were combined with 50 gallons of 
lime-sulphur solution, with the exception of Plat IV, where a com- 
mercial precipitated sulphur was employed. 
Three spray applications against the codling moth were made: (1) 
when petals dropped; (2) 3 to 4 weeks later; (3) 9 weeks after petals 
dropped for second-brood larvae. 
The dropped fruit from certain count trees in each plat was picked 
up weekly and examined. The fruit gathered at harvest time was 
likewise examined and the results recorded. 
Plat I consisted of 9 trees, the fruit from 5 of which was examined ; 
Plat II, 9 trees, 5 examined; Plat III, 4 trees, 3 examined; Plat IV, 5 
trees, 3 examined; Plat V, 9 trees, 5 examined; Plat VI, 7 trees, 5 
examined; Plat VII, 12 trees, 6 examined; Plats VIII, IX, and X, 
total 8 trees, 8 examined. For the results of this experiment see 
Table XVII. 
Table XVII. — Sound and wormy apples from sprayed and unsprayed plats. 
[Benton Harbor, Midi., 1914. Poison (est. Comparison of arsenate of load in powderod and paste form.] 
Plat 
No. 
Treatment. 
Tree 
No. 
Condition of fruit. 
Wormy. 
Sound. 
Total. 
Per cent 
sound. 
I 
Arsenate of lead (powder), \ pound to 50 gallons 
1 
2 
3 
t 
5 
28 
16 
155 
117 
Gl 
lit; 7 
1,036 
3,052 
1,650 
806 
695 
1,052 
3,207 
1,767 
867 
95. 97 
Plat total 
95.17 
93. 38 
92. 96 
377 
7.211 
7,588 
95.08 
Arsenate of load (paste), } pound to 50 gallons 
II 
2 
3 
•1 
5 
387 
221 
222 
355 
128 
6,979 
5, 282 
5,064 
6,098 
3,771 
7,366 
5,503 
5, 153 
3,899 
94 75 
Plat total 
95.98 
95. B0 
93. 19 
96. 72 
1,818 
26, 194 
87>6OT 
85.22 
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