June, 1929] MOSQUITOES OF NEW HAMPSHIRE 13 



CONTROL 



Active attempts at mosquito control were first made after certain of 

 these insects had been shown to carry human diseases. Methods for 

 their control have been perfected in the Panama Canal Zone and the 

 southern states. New Jersey was the first state to initiate and carry out 

 control work against the common, non-disease bearing mosquitoes, the 

 investigations beginning in 1900. Other states and the Federal Govern- 

 ment have continued this work, until now the adequate control of the 

 mosquito nuisance can be accomplished at a cost well within the reach 

 of most communities. 



In the early spring of 1928 the precinct of Rye, N. H., asked the 

 State Experiment Station for recommendations for the control of mos- 

 quitoes. A preliminaiy study was made, and suggestions for control 

 were submitted. In September, 1928, the precinct of Rye appropriated 

 $1500. for mosquito control, and the precinct of North Hampton voted 

 $750 for the same purpose. 



Before undertaking control measures for mosquitoes we should know 

 several facts about the locality in order to obtain the best results: 



1. What species of mosquitoes are present? 



2. When do they occur and what is their relative abundance? 



3. Where do they breed? 



4. What is the most practical and economical method of control- 

 ling or eliminating each breeding place? 



General methods may be given for mosquito control, but each locality 

 presents an individual problem, the solving of which depends on the 

 answers to the above questions, and on the amount of money which the 

 locality is prepared to expend on control work. The following pages 

 give a general discussion of the various control measures. 



OILING 



Oiling is probably the most common and best known method of mos- 

 quito control. It is cheap, effective, readily available, and easily ap- 

 plied. It is obvious that more permanent methods, such as filling or 

 draining, are more effective and cheaper in the long run; but for temp- 

 orary measures or as a supplement to permanent methods, nothing has 

 been found which gives better results than oil. A thin film of oil, spread 

 over the surface of the breeding pools, will kill all larvae and pupse that 

 come to the surface to breathe. 



The number of treatments necessary to control mosquitoes depends on 

 temperature, rainfall, the kinds of mosquitoes present and their life 

 history. The temporary pools which breed most of our early, one-gen- 

 eration, woods mosquitoes, only need treatment in the spring, after the 

 larvae have hatched, and before the adults have emerged. If these pools 

 fill up later from heavy rains, additional treatments may be necessary 

 to control other spfecies. For those speecies which breed continuously 



