66 THE REPORT OF THE No. 19 



Insects Injurious to Vegetable and Garden Crops. 



27ie Colorado Potato Beetle (Doryphora decem-lineata) was not as injurious as in former 

 years. It is probable that the wet season was responsible for the diminution in numbers. 



The Sqiiash Bug (Anasa tristis) Fig. 30, was also not so troublesome as in previous years ; 

 but the Cnriimber-Beetles held their own and did much harm. 



Blister Beetles were not so abundant as usual, probably due to the fact that Grasshoppers 

 have not been numerous for the past two or three seasons. 



Cutworms were reported from North Grey as cutting off young mangolds and cabbages. 

 Tlte Turnip Aphis (Aphis brassicae) did little damage and was not noted in any reports 

 which I received, but the Cabbage-worm (Pieris rapae) was quite destructive not only on 

 turnips but also on cabbages and cauliflowers. 



The Zebra Caterpillar (Mamestra picta) was quite common in most turnip and cabbage 

 fields. (See Fig. 21.) 



At Leamington in Essex County, the Melon Plant Louse (Aphis cucumeris) was very abun- 

 dant in many of the large melon fields. They were kept in check by a careful application of 

 tobacco solution. These insects are greenish-black, and infest the under surface of the leaves; 

 consequently, the tobacco applications must be made to the under surfaces by means of an 

 elbow on the rod near the nozzle. 



Asparagus beetles were not so destructive this year as usual about St. Catharines. 

 The Tomato and Potato Flea-beetles (Epitrix cucumeris) were very abundant. It is of 

 interest, economically, to note the relation of these flea-beetles to the Early Potato Blight, 

 which was prevalent this past season. The edge of the holes eaten by the beetles soon became 

 diseased, and examination showed the presence of spores of the Early Blight (Macrosporium 

 solani). It is probable that the beetles are carriers of the disease from one leaf to another, 

 and it isj more than probable that the dead tissue surrounding the holes made by the 

 beetles forms a suitable medium for the establishment of this semi-saprophytic fungus. 



Early applications of Bordeaux and Paris Green are necessary for the control of the 

 beetles as well as the fungus. 



The Potato Stalk-Borer (Trichobaris 3-notata) Fig. 44, which committed such serious 

 ravages in Pelee Island last year, appeared again this year, but in diminished numbers. 



Many potato-growers on the Island suff'ered greatly, 

 but definite information as to the real extent of the 

 injury done is wanting on account of the more serious 

 damage done by the Late Potato Blight (Phytophthora 

 infestans). The death of the stalk by the fungus may 

 aid in killing the stalk-borer, since the larvfe may be 

 prevented from reaching maturity. Il "is the duty of 

 the potato-growers, however, to take the usual pre- 



FiR. 44.— Potato .stalk-borer: a. grul): h. pupa; tr o i 



c. beetle, all much may nifiert. cautionary measures, viz., to burn the vines in the 



field in the fall, so as to kill the surviving adult 

 beetles, which would otherwise hibernate in the dead stalks. 



Insects Injurious to Orchard Trees. 



In spite of the unfavorable wet season, the San Jose scale increased in large numbers in 

 the infested sections. The pernicious nature of the scale is now impressing itself strongly on 

 the minds of the fruit-growers, and they are coming to the conclusion that the warnings of the 

 entomologists, uttered seven or eight years ago, were warnings which should have been heeded 

 then, and not now. The orchard men themselves must now bear the burden of controlling the 



