The Pocket Gopher. 135< 



a knife, answer the purpose very well. Some correspondents 

 have reported good results from soaking the baits in a solu- 

 tion of arsenic or strychnine. Only a mechanical mixture of 

 either substance can be obtained in water, however, and the 

 presence of particles of the free poison on the surface of the 

 bait would be more likely to cause its rejection than if they 

 were concealed in small slits. Raisins and prunes, treated like 

 the pieces of potato or apple, seem to be very effective baits 

 also. Our experience with specially prepared tablets, sold 

 under patented formulas, does not warrant us in recommend- 

 ing them. 



There is some question as to the efficacy of any sort of scent 

 applied to the poisoned bait. We have tried scented and un- 

 scented bait at the Station without being able tor determine 

 that one was eaten more readily than the other. All claims 

 to superiority in certain proprietary gopher poisons, based on 

 the use of a secret scent, may be set down as lacking the war- 

 rant of practical test. It is true that the sense of smell is 

 probably highly developed in the pocket gopher, owing to the 

 necessities of his underground life, but we lack evidence as to 

 what may appeal to his tastes. Anise oil is often put on baits 

 for various animals, but in poisoning gophers as good results 

 are obtainable without its use. 



About five years ago the state, through a special agent, 

 Prof. D. E. Lantz, purchased the right to manufacture and 

 distribute within the borders of Kansas a certain proprietary 

 poison, the active principles of which are strychnine and 

 cyanide of potassium. This poison was intended to be used 

 in destroying the prairie-dogs on the cattle ranges of the West, 

 but it was found that by leaving out one ingredient the 

 cyanide of potassium a very efficient poison for pocket go- 

 phers could be prepared. After the state's contract with the 

 special agent had expired by time limit, the work of manu- 

 facturing and distributing this poison was turned over to the 

 Department of Zoology and Entomology in the College. The 

 poison is put up in the form of a syrup and sent out in quart 

 cans to any part of the state. On each can is a printed label 

 giving the formula used in preparing the poison and full di- 

 rections for its use. The success attending the use of this 

 syrup is evidenced by the fact that in the past four years we 

 have sent out over 1500 cans. Experiments personally con- 



