' EXPERIMENT STATION REPORT. 651 



carry it tcj the end of the season, though in quite a scaly condi- 

 tion. 



Tree 38. Baldwin Apple. Had been ineffectively sprayed 

 in March, and on June 30th with the Pyrol spray, which yet left 

 a very heavy lot of lan-^e and recent sets. The check was sat- 

 isfactory until August 19th, and the spraying at that time lasted 

 until the 29th, when the third apphcation was made. Infesta- 

 tion increased thereafter until, October 14th, the tree was treated 

 with Kill-O-Scale. 



August 19th, trees i, 2, 7, 18, 24. 30 and 38 were sprayed as 

 before. All of these were resprayings, more or less urgently 

 needed. Rain rendered this application of little efifect, and on 

 August 29th, sprayed trees i, 2, 7, 18, 19, 21, 23, 24, 26, 30 and 

 38. All of these were alsoi re-sprayings. 



In all 15 trees had been treated, 3 of them once only; 4 of them 

 twice, and the others three times, always with the mixture of 

 the same strength. In each case there was a temporary check, 

 the larvcT and recent sets being killed; but always the older scales 

 were left alive and in a week or twO' matters were nearly as bad 

 as before. 



A stronger mixture than that used would be likely tO' hurt 

 foliage and could not be advised; in all, while this horticultural 

 compound is a tolerably good insecticide and would probably be 

 entirely satisfactory against plant lice, it cannot be recommended 

 as against the San Jose, or pernicious scale. 



ROSE-LEAF TOBACCO EXTRACT. 



This preparation is my usual reliance in dealing with such 

 plant lice as appear on roses and other usual garden plants, and 

 I am not particular as to the exact proportions used — getting 

 enough to make a strong tobacco water in all cases. This past 

 season I determined tO' test. it as against, leaf-hoppers and scale 

 larvae. 



July 13th, sprayed my row of grape vines, about 75 feet long, 

 with the extract at the rate of i pound in 5 gallons of water. 

 The vines were infested by the common grape leaf- hopper and 

 had been already sprayed with the Horticultural Compound, 

 July 5th, with very good effect. There were, however, many of 

 the insects yet remaining, and as my neighbor's vine? are much 

 worse infested than my own, I believe part of the supply then on 

 hand came from him. The spraying was done with an adjust- 

 able nozzle, so as to hit the underside of the foliage, and the 



