INSECT ENEMIES OF TOBACCO. 



By Z. P. METCALF, Assistant Entomologist. 



INTRODUCTION. 



The United States produces approximately 1,000,000,000 pounds 

 of tobacco every year. Of this amount North Carolina produces 

 about 150,000,000 pounds, ranking as a State second only to Ken- 

 tucky in number of pounds of tobacco produced. The tobacco-pro- 

 ducing area of the State is divided into two pretty well defined 

 sections, the northern tier of counties bordering on Virginia and ad- 

 joining counties making one section known as the "Old Tobacco 

 Belt," and an eastern section, with Wilson as a center, known as the 

 "New Tobacco Belt." 



The tobacco farmers who grow this enormous crop of tobacco pay 

 each year a large dividend to insect pests, and it is the purpose of 

 this Bulletin to bring together such information concerning their 

 life-histories, natural enemies and remedies as the writer believes 

 will be of interest and value to the tobacco farmer. The number of 

 serious tobacco pests is not large, and most of them are subject to 

 easy methods of control. Yet, regardless of these facts, the damage 

 done to tobacco by insects is growing heavier year by year. True, 

 not all of this loss is preventable, but a large amount of loss may 

 be avoided by proper methods of sowing the seeds, cultivation, rota- 

 tion and various other indirect as well as direct remedies which 

 are indicated below. The details of the life-histories of these insects 

 are given fully in order that the tobacco farmer may understand 

 why certain remedies are used, why they are applied at a particular 

 time of the year, and why no one remedy will be equally effective 

 against all insects. 



For convenience, the tobacco insects are here divided into three 

 classes. Those normally present every year in destructive numbers 

 are discussed under the heading, "Principal Insect Enemies of To- 

 bacco" (page 24). These few pests are responsible, normally, for 

 95 per cent of the injury to tobacco by insects. It is to this class of 

 insects that the farmer must give attention every year. Any insect 

 discussed under any of the other heads may become very destructive 

 at any time, usually depending upon weather or cultural conditions, 

 but they are usually responsible for only a very small amount of 

 the total loss occasioned by insects. The second class of insect? 

 are pests which become destructive usually only under some condition 



