1916 ENTOMOLOGICAL SOCIETY. 29 



INSECTS OF THE SEASON IN ONTARIO. 

 L. Caesar, Ontario Agricultural College, Guelph. 



The past season with its abnormal amount of rainfall has been much more 

 favorable for the development of plant diseases, both fungous and bacterial, than 

 of insect pests. 



Codling Moth (Carpocapsa pomonella). The most interesting thing about 

 the Codling Moth was that in the Niagara district, where the amount of injury 

 done by the second brood is usually very much greater than by the first, this year 

 for the first time in my axperience things were just reversed, the second brood 

 being remarkably small, though the first brood was about as abundant as usual. 

 Probably the excessive moisture was the chief reason for this, though other factors 

 may also have been at work. 



Plum Curculio {Conotrachelus nenuphar). This insect also was apparently 

 less abundant than usual, although the fruit in neglected apple orchards suffered a 

 great deal of injury both from spring and fall attacks. On some trees nearly 

 every apple was deformed. 



San Jose Scale (Aspidiotus pernidosus) . The season of 1914 with its dry 

 summer and long open fall was remarkably favorable for the increase of San Jose 

 Scale. This was not true in 1915, for this year, so far as my observation enables 

 me to judge, the increase has been less rapid than usual. This spring was also 

 favorable for good results from careful spraying. With a single application we 

 were able to destroy almost every scale in an old orchard that would otherwise 

 have been nearly all dead by now. Lime-sulphur, strength 1.035, was used on one 

 part of the orchard ; Soluble sulphur, strength 121/2 lbs. to 40 imperial gallons, on 

 another part, and Scalecide 1 to 15 on a third. All were about equally satisfactory 

 this year. 



Blister Mite [Eriopliyes pyri). For some unexplained reason the increase 

 of Blister Mite, even in unsprayed orchards, the last two or three years has been 

 very slight; in fact some trees seem to have fewer leaves infested than three 

 years ago. 



Leaf-Rollers [Tortrix {Cacmia) rosaceana, T. argyrospila and T. semiferana]. 

 (See p. 163.) 



Capsids Attacking Apples (Neurocolpus nuhilus, Paracalocoris colon, 

 Lygidea mendax and Ileterocordylus malinus). All four of these Capsids were 

 found on apple trees but not all in any one orchard.. Lygidea mendax was found 

 in the greatest number of orcliards, but Neurocolpus nuhilus has apparently been 

 the most destructive. It was sometimes found with Lygidea mendax, but in other 

 orchards was the only species present. Heterocordylus malinus apparently did 

 almost no harm and was much more common on hawthorns than on apples. 

 Paracalocoris colon was also scarce. Lygus invitus is abundant in the Province 

 but has not yet been found attacking appies or pears. Mr. Crawford's paper gives 

 an account of our work on N eurocolpus nuhilus. 



Tent-Caterpillars (Malacosoma americana and M. disstria). These cater- 

 pillars still destructive in the eastern half of the Province, though Mr. E. P. 

 Bradt, the district representative at Morrisburg, informs me that a large per- 

 centage, apparently 50 per cent., of the eggs failed to hatch and fully 50 per cent, 

 of the caterpillars died before reaching maturity. There has been a gradual 

 decrease the last two years in the numbers of both species down east, but this is not 

 true of the western part of the Province, into wliich they are gradually spreading. 



