34 BULLETIN NO. 1, DIVISION OF ENTOMOLOGY. 
day the scales were Joose, and a week afterward the limbs were free and 
clean. Many of the leaves dropped. 
2. Fivelarge twenty-year-old trees having Mytilaspis; dilution a, rosin 
soap; 30 gallons used ; clean within a week; lost most of their leaves. 
3. Five hundred small trees, 2 to 4 feet high, affected with the Lecan- 
jum; used 100 gallons dilution b, whale oil; scale dead the third day ; 
leaves not hurt. 
4, One hundred small trees covered with the Lecanium ; sprayed with 
dilution a, Zamia; scale dead the second day. 
5. Dilution d of b milk sprayed on 20 large trees badly affected 
with Mytilaspis; 100 gallons used. In a week most of the scales loos- 
ened, and 50 gallons more used cleaned the trees of scales. 
6. Dilution b, whale-oil soap; four large trees required but one appli- 
cation to destroy the scale; 12 gallons used of dilution. 
7. Dilution b, Zamia, one large tree; one application apparently de- 
stroyed all scale; 1 gallon used. 
8. Five small trees affected with Lecanium needed two applications 
of dilution ¢, wha!e-oil soap, to clear the trees. 
9. Four large trees having Lecanium; sprayed with dilution d, rosin 
soap. No effect shown the third day. Appled same dilution. Seales 
loose the second day afterward. 
10, Hight large trees; Lecanium and Mytilaspis; 40 gallons of d, rosin 
soap, in which one pound sulphide of potassium was dissolved. Of this_ 
one application seemed enough. 
11. A large tree badly infested with Mytilaspis. Three gallons dilu- 
tion a of a milk destroyed the scale at one application. Many leaves 
dropped a few days afterward. 
12. Four small trees alike affected with Lecanium. Two sprayed with — 
dilution ¢, rosin soap; scale loose the third day. Two sprayed with — 
dilution c of b milk. A few scales alive on the third day. 
13. These experiments were repeated with the general formula of one | 
pound potassic sulphide to 40 gallons of emulsion, with the apparent 
effect of making a dilution ranking as das valuable as that of the a 
grade. : 
J think it reasonable to infer from these experiments : i 
1. The soap solutions are more effective in all grades of dilutions than 
those corresponding of the zamia or milk; the potash doubtless aiding 
in softening the scale. In fact, in many cases, strong solutions of soap 
or potash have been used with good effect upon scale insects. } 
2. After a rain, or in the evening, all applicatious are more effective. 
3. Two or more applications of an emulsion containing 1 or 1.25 per 
cent. kerosene are better than a single one of a5 per cent. or greater . 
percentage of kerosene, and far less liable to injure the foliage. The ; 
expense of making and applying the emulsions is often greater than the 
cost of the material used, and this will most likely cause strong solu- 
tions to be in greatest demand. ‘ 
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