PLANTS AND ANIMAL PARASITES 153 



injuries as some insects and are controllable by the same 

 methods, we do not distinguish between them in the 

 following paragraphs. 



271. Mice. Damage from mice to orchard and 

 nursery trees is very common. Mice are usually more 

 troublesome on sod ground covered with snow, especially 

 beneath snow banks, hence all grass should be removed 

 in autumn from the immediate vicinity of the trees. It 

 is well to ridge the soil a little, at the base of the trees, 

 so that the mice in burrowing beneath the snow will 

 not be likely to come in contact with the stems. Pack- 

 ing the snow immediately about the trees is helpful in 

 preventing damage in winter. The stems of orchard 

 trees may also be wrapped in heavy paper or inclosed in 

 fine wire netting or other protective material. If tarred 

 paper is used, it should be promptly removed in spring, 

 or it may cause injury to the bark. 



Stored seeds of almost all kinds must be carefully 

 guarded against mice. 



272. Gophers are often troublesome by eating planted 

 seeds and by burrowing about the roots of young orchard 

 trees. They may be poisoned by placing corn, soaked 

 in a weak solution of strychnine in water, about their 

 holes. 



273. Rabbits are especially troublesome to nursery 

 trees, when the ground is covered with snow. The 

 most satisfactory protection is to inclose the nursery 

 with a fence of poultry netting, which should be banked 

 up a little at the bottom to prevent the rabbits from 

 passing under. It should be high enough to reach above 

 the surface of the deepest snow. 



Orchard trees may be protected against rabbits by 

 inclosing the trunks with the devices mentioned under 



