38 REFORESTATION ON THE NATIONAL FORESTS. 



The strychnia and saccharin are dissolved in the water by boiling, 

 after which the starch, previously softened with cold water, is poured 

 in and the boiling continued until the solution thickens. This solu- 

 tion is then mixed with the grain until the kernels are coated. The 

 treated bait may be used at once, or it may be dried and kept for 

 future use. In distributing the poisoned grain or other bait the 

 places selected should be numerous, though the quantity left at each 

 may be small, since only a few kernels are required to kill an animal. 

 Poisoning works best when ordinary rodent food is scarce. The poi- 

 son just given for chipmunks and ground squirrels is most effective 

 in spring or early summer. Planting the poisoned seed itself is apt 

 to be unsatisfactory, since the poison is all on the shell and is not 

 eaten by the rodents, which merely extract the kernel and leave the 

 shell. This method may, however, be effective in the fall when the 

 rodents are storing seed and the poison is absorbed as the seed is 

 carried in the cheek pouches of the animals. 



Where mice as well as chipmunks are destructive, the following 

 formula has proven effective : 



Wheat 16 quarts. 



Strychnin 1 ounce. 



Saccharin 1 teaspoonful. 



Melted tallow__. 1 pint. 



Either the alkaloid or the sulphate of strychnin may be used, 

 though the alkaloid on account of its less bitter taste seems prefer- 

 able. The wheat should be warmed in a metal saucepan or small 

 receptacle, and the saccharin and strychnin pulverized and sprinkled 

 over it. The melted tallow should then be poured in and the mixture 

 stirred until every wheat kernel is coated. Tallow is more satisfac- 

 tory than starch as a coating in wet weather, and wheat is more 

 effective than barley, especially for mice. 



In distributing any kind of poisoned grain it is important to put 

 it out of the reach of birds. Ordinarily this is not difficult, Cavities 

 among small piles of stones or under roots or logs, or burrows of 

 animals, will be entered by rodents and ignored by birds. Lacking 

 these, cover made from pieces of bark, boards, or flat stones, with a 

 low runway left beneath, will fill the purpose. Barley is usually at- 

 tractive to rodents and is the grain least relished by birds. 



In some of the National Forests rabbits have damaged plantations 

 of young trees. Where damage of this kind is serious the rabbits 

 should be poisoned in early spring by baiting with twigs cut from 

 fruit trees or native brush. The twigs should be scattered a few 

 hours before sundown along the rabbit trails, or in openings on the 

 plantations. The bait should be prepared according to the formula 

 given for chipmunks and ground squirrels, with the substitution for 

 the barley of 15 pounds of twigs cut into 2 or 3 inch lengths. 



