424 



THE ESSENTIALS OF AGRICULTURE 



more serious pests than are lice, and every reasonable pre- 

 caution should be taken to insure their absence. The eggs of 

 the mites are laid in the filth that accumulates about the roosts. 

 When mites have been discovered in a poultry house, the entire 

 interior of the house should be sprayed at once with kerosene, 

 or with a 3 per cent solution of a good coal-tar stock dip, care 

 being taken to soak the crevices. One spraying is not enough, 



FIG. 217. Interior of a good chicken house 



Showing perches, dropping board, broody coop, feed hopper, and watering appliance. 

 (Photograph from Purdue Experiment Station) 



because it kills only the living mites and does not injure the 

 eggs, particularly if they are well covered. The eggs will hatch 

 in from four to six days in. warm weather, and in from seven 

 to ten days in cool weather, and the time of the second spray- 

 ing should be governed by the temperature. Spraying for mites 

 also helps to guard against other poultry diseases. The chicken 

 house should be thoroughly sprayed at least twice a year even 

 if no mites appear, and it should always be sprayed after any 

 outbreak of disease. 



