16 



HOW TO DESTROY EATS. 



homemade phosphorus poisons for ground squirrels, and entire fields 

 of ripe grain have been destroyed in this way. Even with the com- 

 mercial pastes the action of sun and rain upon them changes the 

 phosphorus and leaches out the glucose until a highly inflammable 

 residue is left. 



It is often claimed that when phosphorus is eaten by rats or mice 

 it dries up or mummifies the body so that no odor results. The 

 statement has no foundation in fact. Equally misleading is the 

 statement that rats poisoned with phosphorus do not die on the 

 premises. Owing to its slower operation, no doubt a larger pro- 

 portion escape into the open before dying than when strychnine is 

 used. 



The Biological Survey does not recommend the use of phosphorus 

 as a poison for rodents. 



Caution. — In the United States there are few laws which prohibit 

 the laying of poisons on lands owned or controlled by the poisoner. 

 Hence it is all the more necessary to exercise extreme caution to 

 prevent accidents. In several States notice of intention to lay poison 

 must be given to persons living in the neighborhood. Poison for rats 

 should never be placed in open or unsheltered places. This applies 

 particularly to strychnine or arsenic on meat. 



Poison in poultry houses. — For poisoning rats in buildings and yards 

 occupied by poultry the following method is recommended : Two 

 wooden boxes should be used, one considerably larger than the other, 

 and each having tAvo or more holes in the sides large enough to admit 

 rats. The poisoned bait should be placed on the bottom and near 

 the middle of the smaller box, and the larger box should then be 

 inverted over the other. Kats thus have free access to the bait, but 

 fowls are excluded. 



Domestic Animals. 



Among domestic animals employed to kill rats are the dog, cat, 

 and ferret. 



Dogs. — The value of dogs as ratters can not be appreciated by per- 

 sons who have had no experience with a trained animal. The ordi- 

 nary cur and the larger breeds of dogs seldom develop the necessary 

 qualities for ratters. Small Irish, Scotch, and fox terriers when 

 properly trained are superior to other breeds, and under favorable 

 circumstances may be relied upon to keep the farm premises reason- 

 ably free from rats. 



Cats. — However valuable cats may be as mousers, few of them learn 

 to catch rats. The ordinary house cat is too well fed and conse- 

 quentl}^ too lazy to undertake the capture of an animal as formidable 

 as the brown rat. Birds and mice are much more to its liking. 



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