16 CIRCULAR 3 81, U. S. DEPARTMENT OF AGRICULTURE 



After the poison has been applied two or three times a few rodents 

 may be left that refused to take the baits or did not find them. These 

 may be trapped. Trapping is better also on planted areas, because 

 intensive cultivation there disrupts the runways, and also in loose 

 soil, where the surface indications are often lacking and the presence 

 of the pocket gophers unnoticed until the bulbs fail to come up or 

 the tops are pulled clown or become wilted. In such cases the run- 

 ways are located with a probe or by the giving way of the ground 

 when walked over. 



The large pocket gopher {Thomomys bidbivorus), found in the 

 Willamette Valley. Oreg., is probably the least troublesome to the 

 bulb grower. Its presence is always indicated by its large mounds, 

 which are usually fan-shaped. It may be controlled by the use of 

 either poison or traps. Poisoned bait is prepared by dusting 10 

 pounds of red clover tops with 1 ounce of powdered strychnine 

 alkaloid. Dig in from the mound and follow the lateral, which is 

 often plugged* with excavated earth, to> its intersection with the main 

 runway, where a handful of the bait is placed. The opening is then 

 carefully closed with clods and soil so as to exclude all light, leaving 

 the runway in as natural a condition as possible. 



A special type of trap is used for this pocket gopher, the details 

 of which may be obtained from the county agricultural agent. Addi- 

 tional information is given in Farmers' Bulletin 1709, Pocket- Gopher 

 Control. 



RABBITS 



In situations where certain summer-flowering bulbous plants, as 

 gladiolus, ixia, and sparaxis, are being grown near brush lands or 

 other cover favorable for rabbits, these larger rodents sometimes fre- 

 quent the plantings at night and nibble the foliage to the ground. 

 Their invasions may be prevented by enclosing the field with a fence 

 of poultry netting, 1 yard wide, supported by temporary stakes. The 

 bottom edge of the fence should be 6 inches in the soil, to discourage 

 the rabbits from digging under. When the rabbits are not numerous, 

 box traps baited with apple, or the timely use of a shotgun will give 

 protection, in lieu of a fence. Measures of control of cottontail rab- 

 bits that may do damage in bulb plantings are discussed in Farmers' 

 Bulletin 702, Cottontail Babbits in Relation to Trees and Farm 

 Crops. 



II S. GOVERNMENT PRINTING OFFICE; 



For sale by the Superintendent of Documents, Washington, D. C. ----- - Price 5 cents 



