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THE MONTHLY BULLETIN. 



APPENDIX. 



DIRECTIONS AND FORMULAS FOR DESTROYING NOXIOUS RODENTS. 



[Note. — The following formulas and directions are adapted from the various publica- 

 tions, reports, contributions, and yearbook reprints of the Bureau of Biological Survey, 

 U. S. Department of Agriculture.] 



CAUTION. 



All poison containers and uncleaned utensils, used in the preparation of poisons, 

 should be kept PLAINLY LABELED and OUT OF REACH of children, irresponsi- 

 ble persons and livestock. 



DIRECTIONS FOR DESTROYING CALIFORNIA, OR "DIGGER" GROUND SQUIRRELS. 



Barley, recleaned grain — 16 quarts 



Strychnin (powdered alkaloid) 1 ounce 



Bicarbonate of soda (baking soda) 1 ounce 



Saccharin 1/10 ounce 



Heavy corn sirup i pint 



Thin starch paste f pint 



Glycerin 1 tablespoonful 



In a clean vessel mix thoroughly 1 ounce of powdered strychnin (alkaloid), 1 

 ounce of common baking soda, and 1/10 ounce of saccharin. Crush all lumps of the 

 soda with mixing spoon. To this add i pint of heavy corn sirup and stir thoroughly 

 to a smooth, creamy paste free from lumps. Over this pour f pint of thin hot starch 

 paste and stir well. (The starch paste is made by dissolving 1 heaping tablespoonful 

 of dry gloss starch in a little cold water which is then added to f pint of boiling- 

 water. Boil and stir constantly until a clear thin paste is formed.) Add the 

 tablespoonful of glycerin and stir thoroughly, making sure that none of the heavy 

 sirup paste still sticks to the bottom of the container. Pour this mixture over 16 

 quarts of good cleaned barley and mix well so that each grain is coated. 



For mixing small quantities an ordinary galvanized wash tub is convenient. For 

 larger quantities a tight smooth box may be used, and the mixing may be done with a 

 spade. 



Each quart of the poisoned grain is sufficient for 40 to 50 baits. This quantity 

 SCATTERED along squirrel trails, or on clean, hard places on the surface about 

 the holes, will not endanger stock. 



N. B. — Strychnin in any form other than the powdered strychnin alkaloid is not 

 effective in the above formula. 



Why Barley Is Used. Barley is recommended, in poisoning with strychnin, be- 

 cause its roughness holds the poisoned coating better and it is usually more attractive 

 to squirrels and far less likely to be eaten by birds than wheat. The above formula 

 makes an entirely coated grain which is more efficient than a soaked grain and kills 

 squirrels more quickly so that they are much more likely to die above ground where 

 they can be seen. This is due largely to the squirrels' habit of gathering grain 

 and carrying it in their cheek pouches. The cheek pouches are within the mouth 

 and are lined with mucous membrane which readily absorbs the poison from the 

 coated grain. When absorbed by the cheek pouches it requires only about one-fifth 

 as much strychnin to kill the animal as it does when taken into the stomach. 



Distribution of Poisoned Grain. The poisoned grain should be well scattered (not 

 placed in piles) along the squirrel trails and clean hard places on the surface of the 

 ground about the burrows. It should not be placed down in the burrows, except 

 when used near farm buildings or poultry yards, upon the mounds too close to mouth 

 of burrows, nor in grassy places. If well scattered it will not endanger livestock 

 and the squirrels are not so apt to hull it. 



Poisoning With Green Barley Heads. In selecting barley heads for this purpose 

 the grain should be in the paste or ripening stage and the long beards should be 

 snipped off with scissors. They should then be immersed in a solution made by 

 dissolving one ounce of strychnin sulphate in a gallon of boiling water to which a 



Note.— To adapt the above formula for use in destroying the Oregon ground squirrel or 

 "Picket Pin," 20 quarts of recleaned oats should be substituted for the 16 quarts o'f wh'ole barley. 



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