THE STALK BORER. 



61 



the latter, the worms tend to congregate therein, brought to 

 a stop by the wall of dirt. These furrows should be about 

 two feet, or more, apart. Better yet, if time and labor are 

 available, is to dig a ditch next the crop which is in danger, 

 since it is harder for them to extricate themselves from a 

 ditch, than from a furrow. Several furrows, however, will 

 check them until they can be killed. Killing can be accomp- 

 lished by putting dry straw on the worms in the furrow and 

 hurriedly firing it, after wetting it slightly with kerosene. Or, 

 kerosene may be poured directly on the worms. This in itself 

 is fatal, but rather expensive. Crushing the worms when in 

 the ditch or furrow by dragging a small log or piece of timber 

 through it is practiced by some. Fall plowing (as late as 

 possible), as in the case of many other of our insect pests, is 

 excellent, as it either exposes many of the pupae where birds 

 can find them, and variations in the weather can affect them, 

 or buries them so deeply that the moths cannot emerge from 

 the soil. 



Some spread dry straw over them when on their food 

 plants and fire it, thus burning them and saving their attack- 

 ing a nearby crop which would otherwise have suffered. In- 

 asmuch as the vicinity of old straw stacks offers an ideal 

 place for hibernation, such rubbish, which is also a haven of 

 refuge for other pests as well, should not be allowed to stand 

 undisturbed for any length of time. 



Fig. 51.— Parasitized Army worms and the fly which attacks them. Slingerland. 



