WAR AGAINST INSECT PESTS 



THE FOES OF AGRICULTURAL PRODUCTION 



C. GORDON HEWITT, Dominion Entomologist, Department of Agriculture. 



Ottawa. 



The Swiss motto, "To cultivate the soil is to serve one's country," is to-day, when 

 the Empire is at war, more applicable than ever to the farmers of Canada. To meet 

 the necessities of Canada and the Empire, it is necessary not only to maintain produc- 

 tion at its usual rate, but to make every effort to increase it to a still higher point. 



Destruction by insect pests is one of the chief factors in reducing the output of the 

 farm. All crops are affected — field, orchard and forest. The aggregate loss to Canada 

 due to these causes is not generally appreciated. When a serious outbreak of an 

 insect pest occurs on a farm, the farmer realizes the extent of his individual loss, but 

 the aggregate loss caused by the continual destruction effected by insects working 

 insidiously in the fields and diminishing crop production as a whole, is comprehended 

 by few. Careful investigation indicates that the loss averages anywhere from ten to 

 twenty-five per cent, of the crop. On the lower estimate the annual loss to Canada 

 from the depredations of insects is reckoned at over one hundred and twenty-five 

 million dollars. Taking the latest figures of crop production, the loss on a ten per 

 cent, basis works out as follows: — 



Field Crops (grain crops, potatoes, sugar beets and 



fodder crops) $80,000,000 



Vegetable Crops 5,000,000 



Stored grain products 5,000,000 



Live Stock (loss in hides, milk and flesh) 30,000,000 



Tobacco 100,000 



Fruit, orchard and small fruits, including losses and 



cost of spraying, etc. (Based on 1911 figures)... 5,000,000 



Total $125,100,000 



Canada suffers proportionately greater losses from insect pests than older countries 

 owing to a number of reasons. The chief reason is that a new and fertile country is 

 being opened up and developed; large tracts of land are being put under cultivation, 

 providing an abundance of food for insects which previously lived in small numbers in 

 restricted cultivated patches or on wild plants. For three thousand miles our territory 

 adjoins that of a country whose development preceded ours, and in the process of this 

 development foreign pests were accidentally introduced with the result that more than 

 half of the worst insect pests are introduced species. Development requires imports of 

 natural products such as trees, plants, seeds, fruit, etc.; such natural products carry 

 pests from their native countries; on establishment in the new country these pests 

 increase more abundantly owing to the absence of their natural enemies, which, un- 

 fortunately, are not imported at the same time. All these conditions are mainly 

 peculiar to a new country. A large proportion of the losses could be prevented, even 

 with our present limited knowledge of control measures. 



We cannot, particularly at the present time, afford to allow preventable losses to 

 occur. Therefore, it behooves every farmer to take steps, or to redouble his efforts, to 

 curtail losses from this cause, and to increase production by eliminating loss. Insect 

 pests are insidious foes, and the fight against them is an incessant war demanding 

 constant watchfulness. In many cases their presence is unknown until their increase 

 has become so great as to cause serious losses. The destruction and loss goes on year 

 in and year out until finally it reaches a climax in a general outbreak. Recent out- 

 breaks of such insects as the army worm, tent caterpillar, pea aphis, locust, cutworm, 

 illustrate this. These outbreaks might in most cases have been prevented. 



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