13 



to turn swirie into a field which is infested with insects which live 

 in any of their staj^es in the ground, or which infest fruit which 

 falls to the irround. 



III. INSECTICIDES. 



Every farmer or fruit grower has long ago discovered that he 

 catniot leave the care of his insect foes to their own special ene- 

 mies, but must enter the list himself and seek out the best modes 

 of attack. Especiall}' during the last few years has the study of 

 insecticides attracted attention, and many new substances have been 

 tried, some of them very useful, some of them of little value, as 

 proved by ample experiment. Other subtances are yet on trial, and 

 at present it is wise to speak guardedly concerning them, while 

 many new insecticides will undoubtedly appear from time to time. 

 One cause of failure in the use of insecticides has been the im- 

 proper application of that which in itself was of value. A knowl- 

 edge, the more complete the better, of the feeding habits, time of 

 appearance and of the different periods of the life of each insect, is 

 essential if the use of insecticides is to be profitable. In more than 

 one instance considerable sums of money and great labor have been 

 thrown away because of mistake in the identity of the insect to be 

 destroyed, because of which remedies useful against one insect 

 were used against another of so different habits that the remedy 

 was wholly unavailing. A notable case of this sort happened 

 some years ago in Baltimore. From the nature of the case no in- 

 secticides can be of universal application ; some are indeed much 

 more generally useful than others, but none can be satisfactory in 

 all cases. Moreover a remedy highly useful when applied at a 

 certain time, may be of no value whatever when used at another 

 time. The time and method of application are often of the great- 

 est importance. Hence when our fruit or crops are infested, the 

 first thing to do is to discover wliat is the nature of the destroyer, 

 its habits, motle of growth, etc., and these being known, we may 

 then go on to devise and apply a remedy with some chance of suc- 

 cess. If the farmer himself is in doubt of these matters, he is 

 always at liberty to make his wants known at the State Experi- 

 ment Station, and, so far as possible, the Entomologist of the 

 Station will srive all needed information. 



