THE OPERATION OF COUNTERODORANTS. 77 



tempting under their cultivation than, their original wild food, and 

 massing it in gardens, orchards, and fields, where the united odors of 

 many acres extend irresistible attraction. Since, therefore, they have 

 unduly multiplied injurious insects, it is their undoubted right and 

 their bounden duty, to diminish their number, if by so doing, while 

 advancing their own interests, they also promote tlie public good. 



The method of protection herein suggested would be attended with 

 the following direct results. Let us illustrate by its operations upon a 

 single food-plant : If, by means of smoke, or other counterodorant, an 

 apple orchard be protected from egg-deposit, the odor-attracted apple 

 insects, failing to recognize it, will wing their way to other orchards. 

 These in turn must be protected. As the area protected increases, the 

 number of eggs deposited in unprotected orchards increases propor- 

 tionately, compelling a resort to preventive means, if remunerative 

 crops are to be grown. When at length not a single well-cared-for 

 orchard offers its odorous invitation, the neglected, worthless ones, of 

 which there are far too many within our State, standing only as nur- 

 series of insect pests, are seized upon and, fortunately, soon de- 

 stroyed. Single trees, scattered here and there, must now be resorted 

 to. The aggregate of food supply has been greatly reduced, and only 

 a diminished number of insects can be fed. In the lengthened insect 

 flight in search of food-plants, insectivorous birds find more abundant 

 prey. The steadily diminishing number of insects are driven back step 

 by step to their native food-plant — the wild crab — upon which they 

 subsisted for long ages before apple orchards of hundreds of acres of 

 delicious fruit were known. The crab, the wild cherry, thoi wild plum, 

 the thorns, with some other members of the fartiiiyof Rosacem, will fur- 

 nish all the food that our one hundred and fifty apple insects require 

 for their support. Here they may feed, unmolested by the economic 

 entomologist, except as he may chance to need an occasional specimen 

 for study or with which to enrich his cabinet. 



Let the apple-tree stand for every other plant that we value, and for 

 which we seek protection, and let the attacking insects of each, in the 

 manner above suggested, be driven from them to their corresponding 

 wild plants ; then shall we have accomplished all that our economic 

 investigations may aspire to. Its complete realization we shall never 

 attain, either by the method now proposed, or through any other ; but 

 in proportion as we approach it, in the same degree will the earth 

 yield her increase more abundantly in willing return to the labors of 

 the husbandman. 



