APPLIED ENTOMOLOGY — HOWARD 393 



ber of workers, damage by insects is increasing rather than diminish- 

 ing; and it has al.'^o become apparent that this increase is due almost 

 entirely to our own methods in agriculture. 



The population of the country is growing rapidly. "Without 

 counting immigration, we are now increasing at the rate of 1,000,000 

 per year, and that rate itself is increasing. Every year we must 

 feed very many more people than the year before. We must be 

 growing more food constantly. Naturally, all these years we have 

 adopted the quickest, the most economical and the most convenient 

 ways of growing these foods. There have been enormous plantings 

 of single and of allied crops. Often there has been very little 

 rotation. In our haste to feed our increasing millions, we have 

 overlooked the fact that we are feeding increasing billions of insects. 

 By our very methods we are giving certain species of insects the 

 most unprecedented chance to multiply. This will force us in many 

 cases to change our methods — to vary our growing and our crop- 

 ping systems. We must realize this at once. 



It is true that more than half our principal crop pests have been 

 introduced accidentally in the course of commerce. With the 

 passage of the plant quarantine act in 1912, we placed a barrier 

 against this danger; but that it still exists is evident from the 

 Florida experience of the last few weeks. And this Mediterranean 

 fruit fl}', the pink bollworm, the Japanese beetle, and the Asiatic 

 bettle, while still more or less local, will probably spread and will 

 utilize to the full the fairly riotous living spread out on all sides. 

 So that, after all, we not only welcome the hundreds of young 

 men who are joining the ranks of the economic entomologists, but 

 we beg for the assistance and cooperation of the farm organiza- 

 tions and the farm leaders and especially the agronomists and the 

 agricultural engineers, and also of the chemists, the physicists, 

 and the plant physiologists. The trained entomologist can follow 

 the life history of a given species. He can study it in all its 

 aspects. He can work out its general ecology. He can find its 

 weak point if it has any. He can find the reasons why it is in- 

 creasing and spreading. Often he can point out how the greatest 

 damage can be avoided by different farming methods. It is then 

 the agronomist who must advise. The farm planners, the farm 

 organizations, the farm leaders must then take hold. 



This is shown very well, I think, in the case of the European 

 corn borer. The great danger from this pest would be nonexistent 

 if it were not for the corn-growing system in a large part of the 

 corn belt. The entomologists have shown tliat for seven months 

 in the year the borer is helpless at the base of the cornstalks. Is it 

 not obviously the duty of some other than the entomologist to 

 find out the most economical and easiest way of getting rid of the 

 cornstalks at some time during that long rest of seven months? 



