V60 



NEW JERSEY ACrRICULTUEAL COLLEGE 



and which pay satisfactory returns. Tlie early brood of laryae in 1905 

 was unusually lieavy, and more spotted fruit than usual was seen before 

 the beginning- of July. But the later conditions were less fa,vorable 

 for their development, and the second brood was not nearly so large as 

 was threatened, ^^otliing new has developed in the life history of the 

 species and no new natural check has been discovered. 



It is not infrequently asserted that there is some natural enemy that 

 IS active on unsprayed trees, and it is undoubtedly true that some 



orchards that have never had treatment of 



X J^a^ij^ ^^^^ ^^^^^ ^^^^® remained remarkably clean. 



/ ':^^58Hk -^^^ ^^^^ ^°^^ ^°^ seem to be due to the pres- 



/ ';.' y^^ffl^Bi e^c*^ *^f «"y parasite or specific disease ; the 



\ mM/m "^^^^'^^ simply do not multiply. Whether 



\ '■^tm *^^^* ^'"^ ^^^^^ ^^ ^^^ surface condition of the 



\ -'"'^ trees or to some physiological peculiarity 



-. -' seems to be incapable of determination at 



Half growrii; showing f/"'"'^' ^^ '' '''^''''''' ^^'°' ^^'^ '°^^' ^'^^^^^'^^^^ 



conditioQ in which winter "^"^t ^^re once badly injured and left to 



"ZZ%Z1Z *'r'™^'™^ ''^'« >" " ""y ^««°™«d and 



va.sta. adapted themselves to the presence of the 



insect. But, on the other hand, the further 

 fact remains that entire orchards of apple, pear, peach and plum have 

 been completely wip^d out by the scale, and that it would be takino- 

 large risks to trust to natural exemption when an infestation is first 

 recognized. 



But, while notliing new in the life history has been discovered it is 

 believed that a somewhat diiferent period of applying insecticides is 

 indicated by experience. Heretofore the tendency has been to postpone 

 the applications to the last possible moment, and we have advised 

 spraying just before the trees made a start. This seems to be hittino- 

 at the insect while it is yet in its dormant and most completely pro- 

 tected condition and before spring development has begun The rea- 

 sons for advising this period has to do with the effect of the insecticides 

 on the trees, and with the belief that late applications would remain 

 long enough to be, m a way, protective as against the first brood. 



Whale-oil soapsuds were found to be destructive to fruit buds if 

 applied in early winter at a strength sufficient to kill the insects 

 Petroleum was found to be more likely to cause injury when allowed 

 to soak for months into a dormant bark than when applied on an active 



