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entomologist to find out the amount of this influence. During the 

 seasons of 1899, 1900, and 1901 the Hessian fly and pea weevil were 

 very prevalent in the southwestern part of Ontario, but through some 

 unknown cause these pests have to some extent largely disappeared. 

 Believing that it would be possible to determine some of these 

 unknown causes, the Ontario Agricultural College has decided to 

 establish small meteorological stations in the various sections of the 

 Province in order to obtain reliable data regarding the temperature 

 and precipitation throughout the year. It is thought that in time 

 some information of value may be obtained based on these observa- 

 tions. 



As I have already noted, the Hessian fly is no longer a serious pest 

 in Ontario, for it has been observed in one or two localities only dur- 

 ing the past season. When we remember that in the years 1900 and 

 1901 the annual loss from this insect alone in Ontario was at least- 

 two and a half millions of dollars, we can realize to some extent the 

 relief which the farmers feel on the disappearance of this fly. 



The pea weevil, which was so disastrous last season, has not been 

 so active in 1903. There is no doubt that weevils are present in large 

 numbers, but the farmers are now well acquainted with the best 

 methods of dealing with this pest. Some districts have discontinued 

 the growing of peas altogether and provided substitute crops. In 

 other districts fumigation with carbon bisulphid is largely practiced, 

 and farmers are careful to fumigate all their seed peas. 



Ontario sells more than $2,000,000 worth of clover seed, and a reli- 

 able buyer told me that not less than one-fourth of the crop had been 

 ruined this year. In some districts the entire crop was destroyed. 

 That the clover-seed midge is the chief cause of the destruction an 

 examination of the infested fields in June clearly showed, but there 

 are other insects working with the midge. The clover thrips was 

 very abundant in many parts, and I am inclined to believe that some 

 of the loss must be attributed to this pest. 



The Grimsby-Burlington district, at the head of Lake Ontario, has 

 suffered severely for many years from the effects of the pear psylla. 

 Last season the injury was very perceptible, and many of the orchard- 

 ists consider the outlook decidedly gloomy for the coming season. 

 The recent experiments against San Jose scale have taught many the 

 value of early spraying with crude petroleum, whale-oil soap solution, 

 or lime-sulphur salt mixture. The orchards which were the most 

 effectively treated for the San Jose scale suffered least from the 

 effects of the psylla. 



For the first time in many years the Grimsby-Burlington district 

 suffered severely from the apple aphis. Previous to this year it was 

 a rare insect, but the injuries done this past season have convinced 

 the fruit growers that something must be done to control this aphis. 



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