52 THE REPORT OF THE No. 36 



Strength of corrosive sublimate : If only one treatment is given use 1 to 

 1000 i.e. 1 oz. to 6*4 gallons; if two treatments or more 1 to 1280 or 1 to 1600; 

 i.e. 1 oz. to 8 or 10 gallons. The weaker strength, 1 to 1600, probably will be 

 preferred by most men but should be applied a little more liberally than the 

 stronger and the soil around each plant very thoroughly saturated. 



Time of the first application: This should be just as the earliest eggs are 

 beginning to hatch, which is usually about four days after egg-laying begins. 

 This time seems to correspond with the date when European plums are almost, 

 but not quite, in full bloom or when American plums are just beginning to 

 bloom. Hence, if plants are set out early postpone treatment until this date. 

 If plants are not set out until European plums are in full bloom or American 

 plums are beginning to bloom or even later, treat in four days after setting out. 

 If three treatments are to be used, the grower, even if he sets out his plants 

 early may make the first treatment four days after setting out and the others 

 at intervals of a week. A good plan and one that is being -gradually adopted 

 by growers is to watch for the first eggs and to begin treatment the second or 

 third day after their discovery. 



(2) Radishes and Seed Beds of Cabbage and Cauliflower: We have found 

 that two treatments of radishes and also of seed beds of cabbage or cauliflower 

 will give an average of about 80% or more absolutely clean plants, most of the 

 remainder being only very slightly injured. 



The first treatment of radishes should be in three or not more than four days 

 after egg-laying begins; so treatment should ibegin preferably one day before the 

 earliest treatment of cabbage. If radishes come up after European plums are in 

 bloom make the first treatment on the fourth day after the iirst plants appear 

 above the soil and the second five days or not more than six days later. The 

 same recommendations apply to seed beds of cabbage or cauliflower. 



Implements used in Treating : For very large fields probably the best method 

 is a wooden tank or barrel supplied with two lines of thin rubber hose and one 

 man to attend to each, controlling the flow by means of his thumb. For ordinary 

 plots up to 12,000 to 25,000 cabbage plants we find that a wooden bucket or pail 

 and a tomato can with a wooden handle about two feet long fastened firmly b> 

 tacks to the folded-over top of the can is a very cheap and rapid method. For 

 radishes use a watering can with the knob removed. 



How corrosive sublimate Controls: It does this in three ways; first it 

 destroys nearly all of the eggs in contact with the moist treated soil ; second, it 

 kills many of the smaller larva? and some ojf the larger; and third, it repels 

 larvse and thus by warding them off from the plant causes them to perish from 

 lack of food. Larva? once buried inside the root tissues usually escape injury. 

 Corrosive sublimate does not deter flies from laying their eggs around the 

 plant. 



ECONOMIC ENTOMOLOGY IN QUEBEC DURING THE PAST DECADE 



Father Leopold, Director of the Oka Agricultural Institute, La Trafpe, 



Que. 



The history of Economic Entomology in the Province of Quebec is intimately 

 related with two Societies in our Province : The Quebec Society for the Protection 

 of Plants from Insects and Fungous Diseases and the Pomological and Fruit 

 growing Society of the Province of Quebec. I had first intended to deal with 



