CUTWORMS AND ARMY-WORMS 301 



enemies. Clean farming through the destruction of weeds 

 along fences and ditch banks will also do much to prevent the 

 prevalence of cutworms. 



Whenever cutworms assume the army-worm habit, their 

 advance may be stopped by plowing a furrow across their 

 line of march (Fig. 183). The vertical side of the furrow should 

 be next to the field to be protected and should be smoothed 

 by means of a spade. Every ten or fifteen feet along the bot- 

 tom of the furrow post holes a foot or so in depth should be dug. 

 -When the migrating caterpillars reach the furrow and find 

 themselves unable to climb up the smooth side, they crawl 

 along the furrow and drop into the post holes, where they may 

 be easily and readily killed by crushing or with kerosene oil. 

 Any caterpillars that succeed in crossing the barrier may be 

 killed by the free use of the poison baits described above. 



