14 JOURNAL OF ECONOMIC ENTOMOLOGY [Yol. 1 



portions of Tennessee. Some observations were made of well sep- 

 arated outbreaks to determine if possible the reason for the unusual 

 attack. In most eases the system of crop rotation and the farm prac- 

 tice were found conducive to the protection of the wintering forms 

 under suitable climatic conditions. In the latitude of Tennessee a 

 general rotation is corn, wheat, meadow. During average seasons 

 corn land, after what is termed the "laying by," becomes foul 

 with weeds, particularly a species of Ambrosia. This land, after 

 the wheat is cut the second year produces a heavy growth of weeds 

 from seeds of the previous year. The weeds are cut and left 

 as a mulch for the meadow. This mulch affords protection for the 

 army worm during winter and early spring of the third season, which 

 results, if a late spring obtains, in the destruction of the meadow crop 

 and the spread of the worms into contiguous fields. These observa- 

 tions place the burden of proof for the outbreak upon the corn crop 

 and the practices prevailing in its cultivation. Preventive measures 

 must be sought in a change in the rotation and possibly in the intro- 

 duction of a new crop. Here agricultural information is demanded. 

 The ravages of the sugar cane borer {Diatrece saccharalis) have been 

 traced to practices of handling the cane during fall planting, windrow- 

 ing, and spring planting, and to the planting of corn on land pre- 

 viously devoted to second-year stubble. Here, again, a change in a 

 rotation system and common practices of handling the crop are in- 

 volved in preventive suggestions. In fact, the best methods of control 

 of many of the insect enemies of a diversified agriculture are to be 

 found in the adjusting of agricultural practice to biologic conditions. 

 Evidence of this may be found in the recommendations for the corn 

 root aphis, the Hessian fly, the cotton boll worm, the tobacco worm, 

 the differential grasshopper, the North American cattle tick, the com 

 root worm, wireworra and cutworm, and many other pests of general 

 distribution. 



The invasion into the Southern States of the Mexican cotton boll 

 weevil, and its effect upon a crop of international importance, enlisted 

 unusual interest in methods of control. Growing out of the efforts 

 made in connection with the boll weevil, more than any other insect, 

 has the relation of detailed biologic study to the cultural methods of 

 remedial relief been emphasized, if not permanently established. Never 

 before have the importance of a study of agricultural conditions and 

 the habits of most plants been so intimately associated in the develop- 

 ment of preventive methods. Our standing with the farming frater- 

 nity and our opportunities to promote entomological investigation in 

 its broadest and most acceptable field seem to suggest an intimate 

 study of conditions that will protect in the most economical way the 



