INSECTS INJURIOUS TO CORN. 321 



Water, as described under chinch bugs, and in that way practically ex- 

 terminate the colony, but, nevertheless, it is a rare thing that such a 

 discovery is made in time. The next best method is to plow a few fur- 

 rows around the badly infested area. These furrows should be as deep 

 as possible, and should have their vertical sides away from the infested 

 area. Post holes should then be dug every six or eight feet along these 

 furrows. When these army-worms start to migrate, as they are sure 

 to do when they occur in quantities sufficient to attract the attention of 

 the agriculturist, they will not be able to readily get across these furrows. 

 Tliey are rather clumsy worms, and once they find they cannot ascend the 

 perpendicular walls they will walk along the furrows in the hope of 

 finding some escape, and will tumble into the holes, where they may be 

 killed by sprinkling with kerosene or by burning them. I have seen 

 hundreds of bushels of army-worms captured in such holes. This method 

 absolutely prevents further damage by the army-worms, and, as a rule, 

 up to the time of marching the damage from army-worms is not a great 

 one ; hence it is a comparatively easy matter to confine the army-worms 

 by this method to a small area and prevent the destruction of large 

 crops. In case the army-worms are on the march or have escaped from 

 the original badly infested area, or in case they are upon a neighbor's 

 premises, and you have fear of their ultimately marching upon your 

 fields, then you should plow furrows about the fields you wish to protect, 

 and in this case the vertical side should be towards the field to be pro- 

 tected. Holes should be dug along these furrows every few feet and 

 the same method of killing the worms resorted to as given above. In 

 case there be some doubt as to whether the worms are coming to your 

 field or not, the furrows may be readily plowed and the digging of the 

 holes left until you are satisfied the worms are approaching. This fur- 

 row and post-hole method has such an advantage over the coal tar, the 

 lines of fire or the dragging of a log through the furrow, that it seems 

 to me unnecessary to discuss them. 



THE FALL ARMY-WORM. 

 Laphygma frugiperda, S. and A. 



INTRODUCTION. 



While, as a, rule, the true army-worm does not occur in devastating 

 numbers in the fall of the year, another insect, the fall army-worm, does 

 frequently occur in immense numbers in the fall of the year, and, like 

 the true army-worm, when the proper food in the locality in which it 

 was born gives out and the insects occur in sufficient numbers, they 



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