188 FRIENDS AND ENEMIES OF PLANTS 



as being of doubtful efficacy. Perhaps the most effectual remedy 

 would be a campaign of extermination undertaken by the State 

 or National government. 



Rats and Mice. The common house rats and mice do a great 

 deal of damage by their ravages on the farmer's stock of seed corn 

 and other cereals. They usually eat only the heart or kernel of 

 each grain of corn, so that it will not germinate or sprout when 

 planted. The field mice do a great deal of damage by destroying 

 the corn after it is planted. To guard against their ravages some 

 farmers have resorted to the plan of soaking the seed corn before 

 planting in water containing poison, but this is hardly practicable 

 in large fields. The common house rats and mice may be held in 

 check by catching them in traps, by poisoning their food, or by 

 keeping around the house cats, rat terriers, dogs, or ferrets. 

 Gophers. These are small animals that do a great deal of 

 damage by burrowing in the ground and by attacking some of our 

 garden plants. Many lawns are frequently ruined by gophers 

 cutting the roots of the grass and causing the sod to die. 



Prairie Dogs. In many parts of the West there are small 

 burrowing animals that look very much like our common squir- 

 rels. They live in colonies or prairie dog towns and do a great deal 

 of damage on account of the many underground passages they 

 construct. Farmers sometimes try to suffocate them with the 

 fumes of carbon bisulphide or try to catch them in traps. 



Moles. These are small animals about the size of a common 

 house rat, which burrow in the ground and excavate elaborate 

 tunnels with their shovel-like feet. They make their tunnels so 

 near the surface that they undermine the roots of grass and small 

 plants. Of course late in the spring with the approach of the dry 

 season this is likely to cause the death of the plants, and steps must 

 be taken to prevent the intrusion of moles among our garden plants 

 at that time. Moles devour the insects that happen to cross their 

 path, and it is possible that the good they accomplish in this way 

 will counterbalance the injury they do the plant when they tunnel 

 through its roots. 



They may be caught in mole traps or snares or killed by poison- 



' ing food and placing it in the ground where they are burrowing. 



Many gardeners also advocate planting castor beans or mole 



