88 INSECTS INJURIOUS TO STAPLE CROPS. 



late in the afternoon. In pasture-lands and in fields that 

 are injured beyond recovery, sheep or cattle could be 

 turned in in numbers with benefit, as they will crush the 

 larvae by trampling upon them.^' 



The worms may often be destroyed, when not occurring 

 in too large numbers and especially while young, by spray- 

 ing the food with Paris green or other arsenicals, and 

 when present in only ordinary numbers like cutworms they 

 may be killed with poisoned bran mash as advised for the 

 latter on page 217. 



'^ Lawns can be freed from the insects by the application 

 of kerosene emulsion, followed with as copious a drench- 

 ing of water as possible from a hose. This remedy should 

 not be employed in bright sunlight or on a hot day, but 

 preferably toward sundown. ^^ 



When the worms occur in armies they may be combated 

 in the same way as the true Army-worm. 



But too much emphasis cannot be placed upon the im- 

 portance of clean cultural methods a7icl the rotation of crops 

 in the control of both this and the true Army-worm. 

 This has been well expressed by Mr. Chittenden (1. c.) as 

 follows: " Kotation of crops should always be practiced, as 

 well as the burning over of fields in the fall, when they 

 are too badly infested to recover from injury. Above all 

 other precautions which it is necessary to take to secure 

 immunity from attack is that of keeping the fields free 

 from volunteer grain and wild grasses, since experience 

 shows that these are the favorite breeding-grounds of the 

 insect; in other words, they attract the female moths for 

 the deposition of their eggs, and when the larvae hatching 

 from these eggs have devoured the grain and grasses which 

 grow in batches they are driven to cultivated fields for 



