BENEFICIAL AND INJURIOUS INSECTS 



antagonists of your enemy. Everything must be cov- 

 ered, for no one can know the precise point at which 

 attack may prove most efficient. The enemy and its 

 manner of life having thus been uncovered, it is pos- 

 sible to devise and wisely employ means of destruc- 

 tion and control. 



How far the organized entomologists have been suc- 

 cessful in their war upon the injurious insects it is well 

 to let them say for themselves.^ "Enormous as is the 

 annual loss which may now be fairly charged to insects," 

 says Mr, Marlatt, "it would undoubtedly be vastly 

 greater if such pests were left absolutely unchecked and 

 no efforts were made to limit their operations. Were it 

 not for the methods of controlling insect pests, resulting 

 from the studies of the Bureau of Entomology and of 

 the official entomologists of the various States, and the 

 practise of these measures by progressive farmers and 

 fruit-growers, the losses from insects would be greatly 

 increased. Familiar illustrations of savings from insect 

 losses will occur to any one familiar with the work in 

 economic or applied entomology in this country. The 

 cotton worm, before it was studied and the method of 

 controlling it by the use of arsenicals was made common 

 knowledge, levied in bad years a tax of $30,000,000 on 

 the cotton crop. The prevention of loss from the 

 Hessian fly, due to the knowledge of proper seasons for 

 planting wheat, and other direct and cultural methods, 

 results in the saving of wheat to the farm value of from 

 $100,000,000 to $200,000,000 annually. Careful statis- 

 tics show that the damage from the codling moth to the 

 apple is limited two-thirds by the adoption of the arseni- 



' See Mr. Marlatt's report for a. d. 1904. 

 307 



