REMEDIAL AND PREVENTIVE iMEASURES 75 



Burning Over Grasslands. — There is probably no general 

 method that can be used more effectively for destroying army 

 worms than that of burning over, in autumn or early spring, 

 grasslands in which the worms are present. As already indi- 

 cated, a portion of the pests appear to go through the winter as 

 partly-grown worms. Consequently it seems well worth while 

 to examine carefully fields in which they are likely to be pres- 

 ent, and burn them over as thoroughly as is possible. Where it 

 can easily be done, this burning is also advisable as a preven- 

 tive measure, even in regions where the worm has not been 

 destructive this year. The burning should also include old rub- 

 bish heaps and such worthless miscellaneous materials as may 

 serve as a hiding-place for this and other injurious insects, either 

 in the larval or moth states. 



