MODERN WARFARE AGAINST GRASSHOPPERS 471 



from 24 to 36 hours for the insects to die after partaking of the poison, 

 a partial paralysis was the result, and no food was taken by the afflicted 

 animal after his poisoned meal. We applied this by means of large 

 field sprayers, the spray covering 23 lineal feet of ground at once, 

 though the ordinary potato sprayers could also be used. Generally 

 speaking about fifty gallons will cover an acre, and the cost per acre, 

 exclusive of labor, is about 30c. This figure would, of course, be in- 

 fluenced to a greater or less extent by the location of the water supply. 

 A tank wagon in the field would naturally lessen waste of time in this 

 connection. The question as to the effect of this poisoned forage upon 

 stock naturally presents itself at this point, and we have reason to say 



Fig. 11. Another View of Our Spraying Outfit. 



that, as used by us, there appears to be no danger from this source. Of 

 course, unrestricted feeding upon grass drenched with a poison spray 

 on the part of animals, forced to use such feed, and allowed no other 

 forage, might, and probably would, have bad results, but in ordinary 

 practice, as applied in a grasshopper campaign in North America, such 

 conditions would not present themselves, albeit the farmer must bear 

 in mind that he is handling an internal poison, cumulative in effect, 

 the partaking of which in large quantities would probably mean death 

 to any animal. 



To be more explicit, the above opinion is based upon several experi- 

 ments we have tried personally at the Minnesota Experiment Station, 

 the following, and last, constituting sufficient proof to warrant the 

 statement. A yearling heifer was placed in an enclosed plot containing 



