PREVENTION BY FARMING METHODS 21 



FALL PLOWING AND CULTIVATING 



One of the best methods of deterring insects from injurious 

 attack, comparable with clean culture, burning over, submersion 

 and the like, is fall plowing and other ways of cultivating. The 

 process may be varied by harrowing, disking, and raking, and 

 sometimes in cases of serious infestation a cross-plowing is 

 advisable. The object of fall plowing is to bring the insects 

 that are feared to the surface where they will be exposed to cold 

 and other elements and to natural enemies such as domestic and 

 wild birds and mammals. This method is particularly valuable 

 to prevent the recurrence of severe attacks and is beneficial for 

 most forms of insects which hibernate under or near the surface 

 of open fields, meadows and like places. It is particularly indi- 

 cated for many insects affecting cereals, cucurbits and some 

 other vegetables, and where corn and other crops subject to 

 injury by white grubs, root- worms and wireworms and other 

 subterranean insects, as well as cutworms, grasshoppers and 

 others, are to be planted in sod or weedy land. Where the forms 

 of insects mentioned are extremely troublesome, the land should 

 be very thoroughly broken, and the insects, whether larvae, pupae, 

 or adults, should be as much exposed as possible. This remedy 

 is very efifective in cold climates since the exposed insects are 

 unable to obtain secure shelter before severe frosts. 



Fall plowing should be practiced for most crops where it does 

 not interfere with other methods of cultivation. 



The numbers of the squash-vine borer can be greatly reduced 

 by lightly harrowing the surface of infested fields after harvest 

 so as to bring the cocoons to the surface, and then plowing in 

 the spring to a uniform depth of six inches or more, so that the 

 adults will not be able to issue. 



Disking, or cultivation with a disk harrow, is particularly 

 recommended against the fall army worm, which hibernates 

 as pupa near the soil surface. A somewhat similar method of 



