METHODS OF DESTRUCTION. 23 



serious sickness of children being caused by eating its attractive berry- 

 like seed vessels. On the Gophers of the experiment station grounds, 

 however, it had absolutely no effect, the animals thriving as well in 

 fields where the spurge was grown as elsewhere. But the author of 

 the bulletin, Mr. E. J. Wickson, states that the soil of the station garden 

 "is a stiff adobe, and cases of success with the plant have been mostly 

 reported from regions with sandy soils. 1 ' (See Bull. 95. Calif. Agi. 

 Experiment Station.) 



METHODS OF DESTRUCTION AND EXCLUSION* 



Bisulphide of carbon.— In most cases bisulphide of carbon is the sim- 

 plest agent for the destruction of Gophers. It may be used as follows: 

 Open the gopher hole where one of the freshest hills has been thrown 

 out. Pour two tablepoonsful of bisulphide on a bunch of cotton, rags, 

 tow, waste, or any such material and push it well down into the hole; 

 then close the opening. The bisulphide quickly forms a heavy suffo- 

 cating gas that Hows down the hole and along the galleries. Where- 

 ever it overtakes the Gopher he is quickly killed. The whole operation 

 is perfectly simple and easy. The only difficulty arises from the length 

 of the tunnels, which is so great that the animals may be beyond the 

 reach of the gas. Hence it is sometimes necessary to open the tunnel 

 and introduce the bisulphide at two or more places. 



The gas has a vile odor. It should be carefully kept from fire, as it is 

 highly iniiammable and explosive; otherwise no danger attends its use. 



Fumigation. — Rude pumps, known as 'fumigators,' by means of 

 which the fumes of burning sulphur may be forced into the burrows 

 to suffocate the occupants, are extensively used in some parts of the 

 West, particularly in California. They are, however, clumsy, expen- 

 sive, and less effective than bisulphide of carbon. 



Trapping. — Gophers are easily trapped, and once exterminated in a 

 field, others do not soon come in. Their manner of traveling is so slow 

 that only those near the edge of a field will work in during a summer. 

 In the spring the males in their wanderings may settle down in a new 

 place, but this does not often happen. The process of trapping is per- 

 fectly simple, although many farmers have assured me that Pocket 

 Gophers can not be caught in traps. Hence a few directions may be 

 useful. Having selected a fresh hill and observed from which direc- 

 tion the earth is pushed out, dig down on that side until the open hole 

 is found. Enlarge the hole sufficiently to admit a Xo. steel trap 

 and remove such loose earth as may have fallen in. The trap should 

 be set very lightly, placed well down in the hole, sunk in loose earth to 

 the level of the runway, and partly concealed by a sprinkling of fine 

 earth. Finding its hole open the Gopher proceeds to repair the breach, 

 in doing which he steps on the trap and is caught. If loose earth is 

 left m the burrow it will be pushed out in front of the animal, covering 

 the trap, so that it will fail to spring. 



