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a little more carefully, and destroyed the majority of the young larvfe. 

 By the 10th of June all the fruit trees had been sprayed. The emul- 

 sion used was made by emulsifying 1 gallon of kerosene and half a 

 gallon of hot water in which one- fourth of a pound of soap had been 

 dissolved, after which a sufficient quantity of cold water was added to 

 make 15 gallons in all. This dilution was insisted upon, owing to the 

 susceptibility of the i)each foliage to strong mixtures. The cost of the 

 emulsion so made amounted to half a cent per gallon. On June 19 

 Mr. Coquillett was sent to Riverside to ascertain the reason for the 

 poor success of the previous sprayings. It was found that a Climax 

 bucket pump and a knapsack sprayer had been used, and that the 

 workman who operated the knapsack sprayer could not be induced to 

 pull down the handle of the sprayer hard enough to make a good spray, 

 since to do this it would be necessary to pull down with considerable 

 force upon his own shoulders. With the bucket pump he did better 

 work, but even here one side of the tree was usually slighted. The exper- 

 iments showed that 1 gallon of diluted emulsion was sufficient to treat 

 5 peach trees averaging G feet in height, and that one man could treat 

 about 250 trees per day. On the 20th of June Mr. Coquillett had 26 

 trees sprayed with a resin wash composed of 20 pounds of resin, 5 pounds 

 of 70 per cent caustic soda, 2^ pounds of fish oil, and water to make 

 100 gallons. This mixture was sprayed during the sunny part of the 

 day upon trees treated with kerosene emulsion ten days previously, 

 and resulted in the almost complete extermination of the insect. The 

 resin wash was found to destroy the scales in a more advanced stage 

 of development than the very dilute kerosene emulsion, while its work 

 was more rapid. The rapidity of the work is of importance, since where 

 a full-grown female is sprayed with kerosene emulsion she may live 

 for three or four days, during which time she brings young ; whereas, 

 if sprayed with resin wash, fewer young scales are produced. The resin 

 wash, however, is readily washed off' by the rains, while the kerosene is 

 more resistant. On the 28th of June Mr. Coquillett was again sent to 

 Eiverside and found that on the 26 trees treated with resin wash follow- 

 ing kerosene emulsion absolutely all the scales were dead. In the mean- 

 time the owner of the orchard had sprayed all the remaining fruit trees 

 a second time with kerosene emulsion, an interval of ten days or more 

 liaving elapsed between the two sprayings. Examination showed that 

 very few of the older scales were still living, while more recently hatched 

 individuals were almost as scarce as the traditional hen's teeth. On 

 July 22 a final examination was made. No living insects could be found 

 upon the trees treated with resin wash, and so few upon those treated 

 with kerosene emulsion that a third spraying would have undoubtedly 

 freed the trees from the insects. The owner, however, was unwilling to 

 go to the expense of a third spraying, but promised to thoroughly apply 

 a strong wash in the early winter. The owner of this orchard is a very 

 busy man, with many other interests, and all the operations were under- 



