INSECTICIDES, PREVEXTIVES, AND MACHINERY. 429 



tect the staple. An example of this is the practice of certain 

 squash growers, who plant early summer squashes to attract the 

 borers, and Hubbards and marrowfats rather late, so as to be 

 unattractive to the moths as compared with the vigorous early 

 plants. The summer varieties may be taken out and destroyed, 

 with all their contents of borers, after an early crop has been 

 picked from them, and this will leave the later varieties free, 

 while it also accomplishes the destruction of an entire brood of 

 larva. So it has been found practicable in the South to protect 

 cabbages from the attacks of the harlequin cabbage-bug by 

 planting an early trap crop of mustard, to which the insects are 

 attracted, and from which they can be gathered by hand or 

 destroyed by spraying with pure kerosene. 



An instance of the use of methods of cultivation we find in the 

 practice of blackberry growers, who, to prevent injury from the 

 red-necked cane-borer, cut off during the latter part of June all 

 the shoots then above ground, and either gather and destroy, or 

 merely allow them to wilt and die. The beetles have all disap- 

 peared at this time and all their eggs are in these shoots. The 

 new canes that come up after this trimming become sufficiently 

 mature and are in sufficient number to make next year's crop, 

 while they are free from any possible beetle attack. 



There are many other ways in which farm practice may prevent 

 injury from insects, and to the intelligent farmer these methods 

 will commend themselves much more than the indiscriminate use 

 of insecticides after damage has been caused. The prevention of 

 attack is always better than the destruction of the insects after 

 injury has been accomplished, and some of these methods have 

 the advantage of effecting a permanent reduction of the injurious 

 species. Further details are hardly in place here, but what has 

 been said will explain the reason for many of the recommenda- 

 tions made in the body of the work. 



