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Slack the lime slowly with small quantities of water in order to get 

 a creamy solution. When thoroughly slacked dilute to 5 gallons, add 

 1 gallon of kerosene, and churn until emulsified (one or two minutes). 

 This mixture was applied April 14 to a peach tree badly infested with 

 Diaspis pentagona, and to several pear, quince, apple, and peach trees 

 not infested with scale insects, the application to the latter being made 

 more particularly to determine the effect of the wash on different 

 kinds of trees. The application whitened the trees, not entirely, how- 

 ever, obscuring the bark. The treatment was very heavy and thor- 

 ough. It is possible that more lime would have been an advantage, 

 making a better emulsion and a slightly heavier wash. This treatment 

 was made at the same time as the Bordeaux wash, referred to above, 

 and experienced the same weather conditions. The effect of this wash 

 on trees was not unfavorable, no injury being noted. 1 The Diaspis on 

 the one scaly tree subjected to the wash were, for the most part, dead 

 or dying by the 17th of April, the wash holding well and still coating 

 the trees uniformly. This lime emulsion is worthy of a more extended 

 trial, and it is hoped that others who have opportunity to test its effect 

 on various scale insects will undertake experiments with it. 



Whitewash. — At the suggestion of Dr. Howard and with the idea of 

 determining the effect of the lime in the several lime washes used, a 

 good sized plum tree thickly infested with Diaspis pentagona was 

 subjected on the same date as the last two experiments to a thorough 

 spraying with a strong whitewash, prepared by slacking 2 pounds of 

 stone lime in a gallon of water. The application left a thick coat of 

 whitewash on the tree, entirely obscuring the bark and leaving the 

 plant snow-white. At the time of treatment the buds had not started. 

 This lime wash held very well except that it cracked and scaled off a 

 little in spots, due to the action of the wind. In the main, however, 

 the bark of the tree remained snow-white and thickly covered for 

 three or four weeks, in fact, at the end of the summer the lime still 

 adhered to some slight extent. The tree came into bloom and leaf 

 later on without any checking from the application. The adult female 

 scales were not affected, apparently, at all by this application, rather 

 to our disappointment, but it was still hoped that the lime coating 

 would remain and prevent the young scales from settling on the bark. 

 The young of this species, however, appeared very late in the spring 

 and, unfortunately, before that time the lime had so cracked and 

 scaled off in spots that little benefit was gained from its presence, and 

 the second brood at least of this species again completely covered the 

 tree. A lighter coating of lime as indicated by the lime, sulphur, and 

 salt wash and the Bordeaux wash, and also the lime emulsion, adhered 



1 The infested peach tree first mentioned subsequently died, not necessarily, how- 

 ever, as a result of the treatment, but more likely in part from this scale infestation. 

 The other peach trees were nor injured, nor did any of the other trees suffer from the 

 wash. 



