Moles are rather easily poisoned by inserting in the runways corn in the milk stage, freshly cut from the ear, and poisoned with strychnine solution.
Moles live in loose and sandy land. If the place is watched, they may be destroyed when they are heaving their burrows. Mole-traps are on the market. (See gophers, p. 243.)
Prairie-dogs may be destroyed by much the same means as are ground squirrels. (See ground squirrel remedies, p. 241; and wood-chuck or ground-hogs, p. 243.)
Poisoning by grain soaked in strychnine solution has proved most successful. The following method has been devised and used by the Kansas Experiment Station: The mixture is in the form of a syrup, composed of the following ingredients (for 1 quart): 1 ounce strychnia sulfate (powdered), 1 ounce potassium cyanide, 11/2 ounces alcohol, 1 pint syrup. One ounce of green coffee-berries is mixed with the white of one egg, and allowed to stand at least fourteen hours. The strychnia is dissolved in a half-pint of boiling water. The potassium cyanide is dissolved in a quarter-pint of hot water and allowed to cool. Add a little warm water to the mixture of coffee and eggs, and mix it with the potassium cyanide. Then strain this mixture through a coarse sieve into the mixing vessel, and add the syrup. Mix the alcohol with the hot solution of strychnine, and add it to the other mixture. Stir all thoroughly. One quart of the mixture is sufficient to poison a half-bushel of wheat or kafir. The mixture must be thoroughly stirred before it is poured over the grain. Two or three pounds of fine corn-meal are stirred in with the grain to take up the extra moisture. On a bright, warm morning in January, February, or March, place half a teaspoonful or less of the bait in two or three little piles at the outside of each burrow occupied by prairie-dogs. A half-bushel of grain should poison 500 to 600 holes.