HOUSEHOLD AND CAMP INSECTS 1 5 



device is greatly increased by systematic moistening of the manure 

 upon*the rack. 



A modified maggot trap consists of a series of tins placed at 

 intervals along the edges of the manure pile, each containing several 

 inches of sand or chaff and sunk so that slits cut in the tins are 

 flush with the surface. The migrating maggots find suitable 

 quarters in these tins, and may be destroyed in large numbers. ^- 



Another type of maggot trap especially effective against blow 

 flies and flesh flies consists of wire netting- containing pieces of 

 meat, fish or similar material suspended over a trough or vessel 

 partly filled with iron sulphate solution. The insects oviposit upon 

 the bait and the maggots are destroyed as they drop into the solution 

 below.^^ 



Fly poisons. Formaldehyde, a 40 per cent solution, diluted with 

 five or six times its volume of water or milk, is one of the safest 

 and most effective. A little sugar or other sweet may be added to 

 the solution. Put the mixture in shallow dishes in places where 

 flies are numerous. This will be more effective if a little bread is 

 added and water or other fluids attractive to flies are not near at 

 hand. 



Sodium saHcylate in a i per cent solution is sHghtly less efficient 

 than formaldehyde. It is less objectionable in a concentrated form, 

 is a solid which does not lose its strength, and in the preparation of 

 the solution a considerable variation in strength is permissible. 

 Futhermore, it can be used on fly papers.^* 



Cobalt is reported as of variable efficiency and peculiarly attrac- 

 tive to flies when used with bread, while bichromate of potash is 

 practically of no value.^^ 



Arsenate of soda 4 pounds, molasses 2 quarts and water 50 gal- 

 lons, applied to manure kills 98 per cent of the maggots, provided 

 enough is used to moisten the surface thoroughly.^® It or similar 

 preparations also destroy flies and their eggs.^^ Arsenate or arsenite 

 of potash may be substituted, and when sprayed on plants in the 

 garden, or applied to bunches of straw hung outside of houses, 

 results in the speedy death of many flies.^^ The deadliness of this 

 poison is a serious drawback to its general use. 



32 Marette. Rev. Appl. Ent., 4:20. 1916. 



33 Noel. Rev. Appl. Ent, 2:68. 1914. 



34 Phelps. U. S. Pub. Health Rep'ts, 31 :3033-35- Washington. Nov. 1916. 



35 Morrill. Jour. Econ. Ent., 7 :268-74. I9i4- 



36 Howard. State Ent. Minn. 15th Rep't, p. 57-6o. 1914. 



37 Rev. Appl. Ent., 3:170. 1915. 



38 Berlese. Redia, 8 :462-72. 1913. ' 



