12 The Bulletin. 



are such well-known farm practices that they hardly need be men- 

 tioned here. In fields that have lain in sod for some time or where 

 there are other good reasons for suspecting the presence of Cutworms, 

 the fields should be plowed deeply two or three weeks before planting, 

 taking care to cover all weeds. Then poisoned baits should be scat- 

 tered over the field as indicated below, under "Cutworms" (page 

 45). In the fields as in the beds every reasonable care should 

 be taken to provide the plant with every favorable stimulant to 

 growth. Proper fertilization and proper cultivation are both means 

 to the same end, a better stand of plants in the field with higher 

 insect resisting power. The intelligent farmer cannot afford to neg- 

 lect these weapons in fighting his insect enemies. 



Deep fall plowing has a tendency to disturb many insects and 

 destroy many others which are hibernating in the soil. This method 

 of fighting insect pests will be spoken of frequently in what follows. 



Rotation of Crops. 



This is another farm practice concerning the advisability of 

 which we need say nothing ; its beneficial results are well known. We 

 need concern ourselves here only with its effect upon insects and 

 with the benefits to be derived therefrom. Just what the rotation 

 shall be is for each farmer to decide for himself after carefully 

 considering his soil, market demands, and various other factors. Ab- 

 solute failure to practice a system of crop rotation is not only ruinous 

 to soil fertility, but is very bad practice from an entomological stand- 

 point. Many insects are confined to a single food plant, many others 

 are confined to a very limited group of plants, while a comparatively 

 small number are more or less general feeders. It naturally follows, 

 therefore, that if a field is planted in tobacco this year that was 

 in tobacco last year, it falls heir to a crop of insects which developed 

 in the tobacco the year before. On the other hand, it follows just 

 as naturally that if a tobacco crop is followed by a very dissimilar 

 crop many of the insects will be starved out. It must of necessity be 

 true, also, that the longer the rotation the more unfavorable the pros- 

 pects for a destructive crop of insects. ISTo one rotation will avoid all 

 insects, and the farmer must study his soil and know, besides, what 

 insects he may reasonably expect in order to determine upon the 

 kind of crops he will have in his rotation in order to avoid as much 

 insect injury as possible. 



Destruction of Suckers. 



Whatever may be said in its favor, the common practice of leaving 

 the suckers to grow up in the field after the tobacco crop is harvested 

 is, from an entomological standpoint, a very bad practice. The last 



