505 
The mostifavorable place for trapping meadow-mice is a broad 
strip of unkept sod along a fence between two corn or grain fields. 
Waste spots in permanent pastures next to cultivated fields are also 
favorite localities; but where weeds and grass are kept down by 
pasturage or tillage, meadow-mice are rare or lacking. Thorough 
cultivation and frequent rotation of crops will prevent these ani- 
mals from becoming a pest. 
As is the case with all the small mammals, climatic conditions 
have a great influence, directly and indirectly, on the abundance of 
these mice. It has been observed that, in general, open winters 
followed by wet summers are most favorable for their increase. 
If an abundance of grain or other food is present also, marked 
increase in their numbers is sure to be noticed. Such conditions 
increase the number of litters and the number in a litter, and prob- 
ably shorten the time required for attaining maturity. 
The enemies of meadow-mice include practically all the carniv- 
orous mammals, the birds of prey, and the majority of our snakes. 
Among the mammals of this county, weasels and skunks are the 
most important agents in the repression of these mice and other 
small rodents. Weasels especially, being fairly abundant, destroy 
large numbers of mice, and thus probably repay in the fields.what 
they cost in the poultry-yard. Hawks and owls are also great 
destroyers of field-mice of all kinds. This species, not being strictly 
nocturnal, more often falls a prey to the hawks than do some of the 
other species. To the nurseryman or gardener a nest of hawks or 
owls in the vicinity is worth many dollars. Other birds also, as 
herons, crows, cuckoos, shrikes, and bitterns, destroy these mice. 
If only a limited area is to be cleared of meadow-mice they may 
be trapped. The small, single spring traps used for house-mice are 
the most satisfactory. They may be baited with oatmeal and placed 
near the runs. Some are successful with an unbaited trap put 
across the runway. Over a larger area they may be cleared out by 
poisoning. The poisoned bait is prepared as described in the note 
following this paper. It should be so placed that neither birds nor 
domestic animals may get it. It is best to place it in the vicinity 
of their nests under boards slightly raised, or in pieces of small- 
sized tiling, old cans, or the like. One must bear in mind, however, 
that in using poison one always runs some risk of doing damage. 
