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Insects in the soil are able to live with very little or 

 no food over the short interval which often ensues 

 between two crops, and when these are of the same or 

 nearly the same kinds the increase in the pests may be 

 enormous. If, however, a crop which is entirely nnsuited 

 to the pests is planted between two similar crops, they are 

 starved out. 



Ploughing, forking and hoeing are useful agricultural 

 practices as preventive measures, because they expose a 

 large number of insects to attacks of natural enemies. 



Cultivations of tree crops should receive the same con- 

 sideration in the application of preventive measures as 

 field crops. Prunings and dead wood of all kinds should 

 be gathered and burned, or buried deeply enough to prevent 

 the emergence of any insects which they may contain, and 

 also to prevent adult insects from gaining access to them 

 for the purpose of egg-laying. 



In dealing with the pests which attack man, the great- 

 est importance attaches to preventive measures. Mosquitoes 

 breed in stagnant water which may be accumulated in 

 swamps, ponds, pools, old tins, bottles, etc., in cisterns and 

 water tanks, and even in hollows in plants, or in the sheath- 

 ing bases of leaves of such plants as the wild pines. The 

 removal of these breeding places, or the treatment of them 

 to make them unsuitable for the purpose, and the destruction 

 of the mosquito larvae by the use of kerosene, will have the 

 eftect of preventing mosquitoes from becoming numerous. 

 Cisterns and tanks may be enclosed with wire mesh, and 

 they may be stocked with the fish known as millions. 

 Millions are also useful in ponds and swampy situations. 



House-flies may be kept in check by the proper treat- 

 ment of manure and all decaying organic matter which 

 would furnish a breeding place for these pests. The occur- 

 rence of fleas and bed-bugs in numbers can be prevented by 

 the adoption of the necessary precautions and cleanliness. 



With regard to the occurrence of the insect and mite 

 pests of domestic animals, the same rules in reference to pre- 

 cautions and cleanliness hold good. 



Household pests may also be controlled to a large extent 

 by similar means 



All food materials should be kept from these insects, as 

 far as possible ; repellent substances should be freely used, 

 and the utmost regard paid to cleanliness. 



