62 THE REPORT OF THE [ No. 19 



INJURIOUS iNSEOrS IN ONTARIO DURING 1900. 



Bt Dr. James Fletcher, Dominion Entomologist, Ottawa. 



The practical entomologist has had his hands full during the past season in Ontario^ 

 The sfason has b^en a most unusual one — hot and dry in son e sections, but unusually 

 wet in others. There have not been, however, any very renarkable outbreaks of injurious 

 insects which have been the cause of widespread loss ; but some of the old and well known 

 pehts have done a considerable amount of harm, much of which could have been prevented 

 if farnieis would only recognize that they have every year to reckon with the generally 

 forgottfn but always present tax collectors belonging to the insect world tind that these 

 alw ys work in the same way. Orchard insects, which could have be^m controlled by 

 8pra)ii.ig, were negUcted in many places, and Cutworms caustd losses which could have 

 been prevented. The Pea Weevil, every year abundant and destructivp, seems this year 

 to have been rtiore so than usual, but the Destructive Pea Aphis was not so injurious as at 

 one tin e it was feared it would be. Lite in the season it was f und that great harm was 

 being d^ne by the Hessian Fly throughout western Ontario, most particularly in early 

 sown wheat. The Turnip Aphis was only locally prevalent. The San J< ^d Scale has 

 spread over mar y orcharHls which were only slightly affected in the beginning of the 

 season. The so-called Buffalo Moth is becoming a serious pest and is spreading. 



' Cereals. 



By far the most serious outbreak among cereals was by the Hessian Fly (Cecidomyia 

 destructor, Say, Fig 14, highly magnified) in fall wheat. Specimens cf young wheat plants 

 inlestt d to a remarkable degree, some of the shoots containing nearly a dozen puparia, 

 were received from Waterford, Ferguson, and other places. Very 

 few reports of iijary by the summer brood came to hand, so that 

 this sudden appearance of the insect in such large numbers was 

 somewhat of a surprise. Reports from correspondents show that 

 late town grain was to a marked degree less infested than that 

 sown at the usual tiiue in the beginning of S-'ptember. The 

 appearance of the perfect insects, — tiny tilack sh gnats not ex- 

 panding more than a qiarter of an i- ch from tip to tip of the 

 outspread wingp,--and the life history »re so well known that it 

 is nrt m c^ ssmj again to go into details here with regard to th'^se ; 

 suffi e it to say that there are two broods in ihe year, the perfect 

 flies of the first appea>ing in May and June, tind laying their eggs 

 on the leaves of the growing wheat plant The small maggots ^'&- 14.-Hes8ian Fly. 

 work their way down inside the shealha of the leaves and attack the tissues of the grow- 

 ing st«nt, weakening it and frequently causing it to fall down, bending over just above 

 the print of attack. The brown fl ix-h. e<l-like puparia maj fr< q'lently be found in s^raw 

 or undf r the machine at the time of ihrephing Some of these flax seeds the number vary- 

 ing according to the season, produce the flies the same autumn, chi»fl} in the month of 

 SeptemV'er ; these lay their eggs on the newly sown fall wheat, Some of the flies cf the 

 summer brood, however, do not emerge until the following spring — at the same time as 

 the flies rf the autumn brood — and tbesH lav their eggs on the young p'an's of spring 

 wheat. This attack is frequently overlonkt d, owing to th' fact that, if the wheat plants 

 are not sufficiently advanced for the eggs to bn laid upon the stem leavug, they are laid 

 open leaves cloi-e to the ground and the lar>£e attack the root shoots and kill th^m before 

 they huve )prodiiced stems at all. 1 fin«t that, as a gene-al thing, there s a great deal morfl 

 ii jury done in tbts way than on the stems of whoat. Fokriners, as a ruin wit;h this attick, 

 do no*^ re<;< gmze their enemy and attribu'ei the ihin crop to '' c >ld or wet springs," "late 

 froett," •' hot sons," or othe- imaginary causes ' f which no exact re -ord had been kept. 

 As plated abt ve, there is thii autumn a veiy serious attack by the He-sitn Fly in our 

 Ontario wheat fields, particularly in thobe sections where fall wheat is most large'y 

 grown. As a matter of fact, fail wl eat cnn be grown in every ooun y of the Province, 

 and the Hessian Fly is liable to occur in any of these. Certiin areas, however, from the 



