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left long in the ground after maturity are eaten, and the injury is 

 attributed to moles, because tunnels supposed to be the work of moles 

 lead to the place of damage. I have investigated numerous cases 

 of such injury and have invariably found either that the tunnels were 

 made by pine mice, or, if mole tunnels, that they were frequented by 

 mice. Traps set in the tunnels at the potato hills captured pine mice, 

 and the starchy material found in the stomachs of those caught proved 

 that they, and not moles, had been eating the potatoes." 



REPRESSION OF FIELD MICE. 



TBAPPING. 



"Trapping is a simple way to destroy field mice, but it is seldom 

 resorted to because few people have patience to follow it up persist- 

 ently and to look after the necessary large number of traps. When 

 field mice are abundant it is essential to use many traps and to con- 

 tinue trapping for several weeks. Equipped with a hundred or more 

 effective traps, a good trapper should be able to make decided inroads 

 upon the numbers of the pests, if not to practically exterminate 

 them over a limited area. 



"Trapping has special advantages for small areas, such as lawns, 

 gardens, and vegetable or nursery pits and packing houses, where a 

 limited number of mice are present, and wherever, for any reason, 

 there are objections to the laying out of poison. 



POISONING. 



"All things considered, strychnine is the most satisfactory poison 

 for field mice. Although a very deadly substance, it is less dangerous 

 to handle than either phosphorus or potassium cyanide. Its extreme 

 bitterness renders it less liable to be mistaken for a harmless drug. 

 Nevertheless, every precaution should be taken in handling it. The 

 strychnine salt most used commercially is strychnia sulphate. This 

 is the best for poisoning purposes, since it is soluble in boiling water, 

 while the alkaloid requires the presence of an acid for its solution. 

 To disguise the bitterness of the poison when employed for rodents, 

 sugar is used, or the strychnine may be mixed with its own bulk of 

 commercial saccharine. 



"For poisoning field mice various baits may be recommended, such 

 as wheat, oatmeal, and corn, among the grains, and seeds of various 

 plants, as the tomato, dandelion, sunflower, and others. The bait 

 should be soaked over night in a poisoned sirup, which may be 

 prepared as follows: 



