THE CANADIAN HORTICULTURIST. 



161 



all of them, both picked and fallen, 

 16,529 in number, were examined in- 

 dividually for insect injuries, and those 

 due to the codlin moth and curculios 

 were separately noted. 



The examination of 2,418 apples 

 from trees sprayed with Paris green, 

 and of 2,964 others from trees not so 

 sprayed, showed that 21 per cent, of 

 the poisoned apples were infested with 

 the codlin moth, and 69 per cent of 

 those not poisoned, while 22 per cent, 

 of the i)oisoned lot had been infested 

 by the curculio, and 20 per cent, of 

 those not sprayed. Thus, treatment 

 with Paris green had been entirely 

 ineffective for the curculio, but had 

 saved something more than two-thirds 

 of the apples, and it should be remem- 

 bered that the Paris green not only 

 protects the apples, but, by destroying 

 the insects, lessens the amount of future 

 injury. Analysis of a])ples one week 

 after spraying with Paris green, a 

 lieavy storm intervening, gave abun- 

 dant evidence that this insecticide could 

 not safely be a{)plied for some weeks 

 preceding the harvesting of the fruit. 



The comparison of 1,205 apples from 

 a single tree sprayed with London 

 purple, and 2,036 from a tree not so 

 treated, showed that 49 per cent, of 

 the former were affected by the codlin 

 moth, and 59 of the latter. Also that ' 

 •-3 per cent, of the first lot of apples 

 had been invaded by curculios, and 

 1*3.6 per cent of the second lot. The 

 I^ondon purple thus saved about one- 

 sixth of the apples which would have 

 been sacrificed to the codlin moth, and 

 was without effect on the curculios. 

 < Comparing these results with those of 

 tlie Paris green experiment, it must bp 

 r<;mem))ered that the spmying with 

 London i)uri)le began four days later 

 than with Paris green, and that only 

 half the amount was used, though both 

 were applied to the limit of serious 

 damage to the foliage. 



From a tree treated with lime, 1,706 

 apples, as compared with 1,825 apples 

 from a check tree,, show that 54 per 

 cent, of the former contained the apple 

 worm, and 50 per cent, of the latter, 

 thus indicating the uselessness of this 

 substance against the codlin moth. 

 The curculios were entirely unaffected, 

 and it may be fairly concluded from 

 these experiments that it is useless to 

 attempt to combat the plum curculio 

 in the apple orchard by insecticide 

 applications to the fruit. 



As bands for traps serve only to 

 captiire the apple worm after it has 

 done its mischief, and hence interpose 

 only a general })rotection, and are liable 

 to be rendered ineffectual by the neg- 

 lect of one's neighbors, the use of Paris 

 green will serve at least as a valuable 

 addition to remedial measures. Since 

 it may be safely applied only to the 

 Spring brood, it is best to use both 

 bands and insecticides, each measure 

 supplying the deficiencies of the other. 

 Final Conclusion. — Attending only 

 to the picked apples, and condensing 

 our statement of results to the last 

 extreme, we may say that under the 

 most unfavorable circumstances Paris 

 green will save to ripening, at a pro- 

 bable expense of ten cents per tree, 

 seven-tenths of the ap|)les which must 

 otherwise be conceded to the codlin 

 moth, that Tjondon purple will appar- 

 ently save about one-fifth of them, and 

 lime will save none. Furthermore, 

 all these applications are without effect 

 on the curculios in the apple orchard. 



THINNING FRUIT. 



When plant<^d in good soil, good 

 thrifty fruits will nearly always over- 

 load themselves, and in order to secure 

 the best, smoothest and largest fruit, 

 considerable thinning must be done ; 

 this is especially the case with grapes 

 and tree fruits. 



