324 TRANSACTIONS OF THE HORTICULTURAL 



against the second brood of apple worms. He seems to me, 

 however, to leave out of account the fact that the number of the 

 second brood would be very greatly diminished by early spraying, 

 if this was thoroughly, persistently and generally performed; 

 since, whatever the per cent, of reduction in the first brood, the 

 number of the second must be correspondingly reduced, as it 

 descends immediately from the first. That the cherry and plum 

 may be protected from one-half to three-fourths of the curculio 

 injury to which they are subject, by a use of arsenites which 

 could hardly be considered excessive, seems well settled, espec- 

 ially by the reports of Weed and Cook. 



Finally, subjects for experiment are suggested by the partial 

 results already obtained with the Bordeaux mixture, either alone 

 or with London Purple, and with carbolic acid and plaster, a pint 

 to fifty pounds. 



DISCUSSION 



L. R. Bryant asked in regard to the effects the spraying would 

 have on the apple as it grew larger. 



Prof. Forbes — We sprayed eight times and were unable to see 

 that the last brood was any way affected by the late sprayings, and 

 concluded that five times was as good as eight. The right time to 

 spray is just after the blossom is fallen, when the apple is about the 

 size of a pea. The weather, no doubt, has something to do with 

 the injury of the foliage, but have not as yet made any experi- 

 ments to ascertain what it has to do with it. 



Mr. Goodrich — My experience in spraying the peach for the 

 curculio was more negative than favorable. I used London Purple 

 as it did not clog the machinery so bad. I sprayed twice, and 

 when ready for the third time, found that the leaves were drop- 

 ping badly and did not spray again, there being about as many 

 leaves on the ground as on the trees. The poisons vary in 

 strength and think perhaps the solution I used was a little too 

 strong. Three ounces to fifty gallons I think is strong enough for 

 the peach, as it is very sensitive. My experiment killed con- 

 siderable of the fruit but enough remained for a full crop. 



M. L. Dunlap — The percentage of arsenic in poisons is a very 

 important thing and the compounds used should, I think, be ana- 

 lyzed, so we may know the per cent, of arsenic they contain. I 

 believe we should have them analyzed by some one and stamped 

 so that we will know how to make our solutions the right strength. 

 Paris Green and London Purple may be bought at different times 



