14 CIRCULAR 3*81, U. S. DEPARTMENT OF AGRICULTURE 



earth pushed from the burrow in irregular dumps around an exit 

 that is freshly made or an old one reopened for the purpose. 



Pocket gophers cannot be so easily excluded from bulb beds by 

 barriers in the soil as are moles, for they wander about more fre- 

 quently on the surface at night or when disturbed by agricultural 

 operations, than do moles. Pocket gophers are not difficult to con- 

 trol, however, as they take poisoned bait readily and are easily 

 trapped with simple devices adapted to their peculiar habits. Traps 

 will usually enable the home gardener to keep the premises free 

 from this rodent pest, In operations on a larger scale, however, 

 poisoned baits may be used to better advantage. 



Some of the simplest and most effective of special pocket gopher 

 traps are shown in figure 9. These are intended to be set in the 

 open throats of short laterals leading from the main runway, where 

 dirt has been thrust out. If entrance is made into the burrow itself, 

 two traps must be set, one facing each way, the trigger ends adja- 

 cent. The trap must be pressed down firmly on the floor of the 

 run to prevent its being pushed out or upset. It should also be 

 secured by a small stake and heavy cord, or light pliable wire, so 

 that it will not be dragged back by the pocket gopher into the run- 

 way, or carried away by a cat or other prowling animal and lost Avith 

 the catch. By covering the jaws of the trap with fine soil as it 

 is placed within the runway, and excluding light at the point of 

 entry, this trap sometimes proves effective also with moles. This 

 manner of setting is of advantage where both moles and pocket 

 gophers use the same burrow. 



Other pocket gopher traps are on the market, one in the form of 

 a small wood or metal box without bottom or front end. More time 

 is required to set this, as the runway has to be excavated more exten- 

 sively to adjust it. In cases where a pocket gopher learns to avoid 

 some other trap, it ma}^ be caught in some type of box trap. A good 

 tool for use in setting pocket gopher traps is a strong plant trowel 

 with a narrow blade. 



Excepting the Willamette Valley pocket gopher, which prefers 

 green food, all the Pacific coast species readily take sweetpotatoes. 

 Carrots are well taken in some localities as also are the tender tips 

 of green alfalfa. In the Midwestern States pocket gophers of 

 the genus Geomys take heavy steamed-rolled oats as well as the vege- 

 table-root baits ; they also accept wheat, but not so readily. 



The vegetable-root baits, cut into pieces one-half inch square and 

 iy 2 inches long, are dusted with powdered strychnine alkaloid in the 

 proportion of 16 quarts of bait to 1 ounce of the poison. "When 

 alfalfa tips are used, 10 pounds are dusted with 1 ounce of the strych- 

 nine. The poisoned gram may be obtained through the county agri- 

 cultural agent. 



The poisoned baits, two or three pieces, may be introduced into the 

 pocket gopher's burrow through an opening made with a probe con- 

 structed of i/2-inch iron pipe, or with a plant trowel, at places where 

 fresh dirt has been pushed out. The openings should be closed 

 afterwards without covering the bait or disturbing the runway any 

 more than necessary. Two bait placements should be made to every 

 system, the extent of which, though generally difficult to determine, 

 may be gaged by the arrangement of fresh mounds on the surface. 



