314 FARM FRIENDS AND FARM FOES 



chief sources of food, and in consequence they often do 

 great damage in orchards, especially those recently set. 

 Trees of good size are girdled, while small ones may have 

 the bark nearly all torn off the trunk. As this is done in 

 winter under shelter of the snow, the owner may not sus- 

 pect any damage until it is revealed in spring. 



The Common Meadow Mouse multiplies very rapidly. 

 The average is about four litters of young each year with 



Wild Morninq-qlory Roots Stored by Meadow Mice 



about six in each litter. It has been estimated that if there 

 were no destruction by enemies, "a single pair and their 

 progeny in five seasons would amount to nearly 1,000,000 

 individuals." This of course does not happen because 

 many are killed in various ways, but the estimate shows 

 how rapidly these pests multiply under favorable condi- 

 tions. It also indicates the necessity of providing as many 

 natural checks upon their increase as possible. 



In the great prairie regions of the Middle West the 

 Prairie Mouse is abundant and destructive to a great 

 variety of crops. It is distinguished from the Common 

 Meadow Mouse chiefly by its shorter tail, which is not 

 much longer than the hind foot. 



The Prairie Mouse is most likely to develop in neglected 

 fields and meadows, from which it scatters into surround- 

 ing localities. In range pastures that are not closely 

 grazed, these mice are likely to develop in grassy tufts 



