128 REPORT UNITED STATES ENTOMOLOGICAL COMMISSION. 



method as to reduce the loss and the cost and labor of defending his 

 crops to a minimum. It will, in a great measure, do away with that 

 feeling of alarm the locusts usually inspire. But still the warfare will 

 go on indefinitely. While it is almost certain that, on account of the 

 wide-spread area of the West in which the migratory species appears 

 to be indigenous, including in its bounds a large extent of mountain 

 country, it will be impossible by any practicable means to utterly exter- 

 minate it, yet there are strong grounds for believing that a complete 

 knowledge of its history, habits, and habitats will render it possible to 

 prevent, in a great measure, its disastrous incursions into the Missis- 

 sippi Valley. 



We may say truly that one step has been accomplished, for the expe- 

 rience of last season has sufficed to convince the farmers and citizens of 

 the locust- visited sections when another contest comes they will be able 

 to defend their crops from the young insects. 



We feel justified, therefore, in affirming that, although favorable sea- 

 sons for their development will in all probability cause their return at 

 irregular periods, they will never cause such alarm in the future as they 

 have in the past j and that, although they may occasionally cause a tem- 

 porary check to, they never can entirely bar, the agricultural progress 

 of the vast area they lately so fearfully ravaged. 



Simply fighting these insects fortunately does not exhaust the reme- 

 dies in the power of the agriculturists of these sections. The facts ascer- 

 tained render it quite probable, in fact almost certain, that even should 

 the incursions of the locusts continue to occur in the future, and no 

 means of preventing this be found, a modification in the methods of 

 farming or a change in agricultural operations can be adopted which 

 will render the effect of these invasions comparatively harmless. 



As a rule, which has few if any exceptions, the invading swarms do 

 not make their appearance in the Mississippi Valley until the latter part 

 of July or first of August. By this time wheat, barley, and oats have 

 generally reached perfection and been harvested. This fact renders it 

 possible to anticipate these swarms and prevent serious injury by rely- 

 ing chiefly upon these crops when there is reason to fear their incur- 

 sions. 



If the hatching grounds from which these swarms usually come can 

 be definitely ascertained, and the national government, by means of the 

 Signal Service Corps or otherwise, will take measures to give notice in 

 advance of heavy egg-deposits in this area, the farmers, by planting 

 small grains, may thus prevent any serious injury by them when they 

 arrive. This remedial measure applies more particularly to the central 

 and southern sections, as Nebraska and Iowa and southward. In these 

 sections it appears to be also true as a general rule that the young 

 locusts acquire wings and commence migrating sufliciently early in the 

 season to allow corn of rapid growth to be produced after they depart. 

 Hence when the ground is full of eggs and young locusts are expected 



