24 THE REPORT OF THE No. 36 



The Raspberry Sawfly {MoiiopJuidnoides riibi) was unusually abundant 

 this year and many raspberry bushes were badly injured by it. In an experiment 

 with arsenate of lead (8 lbs. to 40 gals.) 100 per cent, of the ilarvge were killed, 

 but unfortunately the spray severely burned the raspberry foliage. This injury 

 was not due, as one would suppose, to an excessive amount of arsenic oxide in 

 the arsenate of lead, because according to an analysis made by Dr. Shutt, Dominion 

 Chemist, only .31 per cent, of the soluble oxide was present. Can anyone present 

 suggest a factor or factors which might have been responsible for the burning 

 of the foliage? 



The Currant Worm {Pteronus ribesii) and the currant aphid (Myzus ribis) 

 were very plentiful this past season. 



White Grubs again proved themselves to be relentless enemies of the straw- 

 berry grower. In the strawberry plantation of the Vineland Experimental Farm, 

 ■SL large percentage of the plants had to be dug up because of white grub injury 

 to the rootsi 



Field and Truck Crop Insects. 



Pea Aphis (Macrosiphum pisi). There was a serious outbreak of pea-aphis 

 this summer in Grantham township, near St. Catharines. When I visited the 

 infested fields during mid-July, I found the outbreak on the decline, due to the 

 effective work of coccinellids, their larvae, syrphid maggots, aphis-lions and 

 braconids. Unfortunately the work of these checks came too late to prevent 

 serious injury to the pea crop. 



On the Vineland Experimental Farm I noticed that where peas were grown 

 under irrigation (overhead system) the aphids were satisfactorily controlled by 

 a fungus, Entomophthora aphidis. 



The Army Worm (Leucania unipuncta). In regard to the remarkable 

 prevalence of army worm in Ontario this year, I am pleased to say that the out- 

 break in the Niagara District was comparatively very light. Com suffered more 

 than any other crop. 



Asparagus Beetles (Crioceris asparagi and C. diiodecimpunctata) were un- 

 usually destructive in some localities. 



Squash Bugs {Anasa tristis) and Cucumber beetles (Diabrotica vittata) 

 were responsible for a comsiderahle amount of damage to cucurbits. 



The Potato Beetle ( Leptinotarsa decemlineata) was remarkably scarce, at 

 least in Vineland locality. . In my own plot of potatoes I did not find a single 

 beetle. 



The Cabbage Butterfly (Pontia rapcp.) was quite abundant. 



Insects Attacking Trees and Shrubs. 



Datana Caterpillars. Black Walnut trees were, in some cases, almost 

 completely defoliated by Daiana inteqerinnva. and the larv;© of T). viinisfra were 

 found feeding on American Elm and Basswood trees. 



San Jose Scale (Aspidiotus perniciomft'). A young Black Walnut tree on 

 the Rittenhouse school grounds, Vineland Station, was killed by this destructive 

 scale this year. 



Elm Aphids. Scotch elm trees growing in the vicinity of the Experimental 

 ffkTVH were attacked by the leaf curling species (Schizoneura nlmi) (fodiens) and 

 hy the gall -maker (Tetraneura iilm.isaccuH) . 



