16. 



the orchard during the winter months. 



Periodic checks during the winter months, particularly after 

 a thaw, may reveal spots still having meadow mouse infestations. 

 A few tablespoonfuls of mouse bait, poured into the holes, may 

 give added protection for the remaining winter m.onths. 



Pine Mice 



Pine mice are an underground species found in many orchards 

 in the Northeast. Their location in the orchard may be restricted 

 to a portion of a tree block or to a single tree. These mice 

 damage apple trees by girdling the root system. This form of 

 injury may not be readily apparent until the tree loses its vigor, 

 the leaves take on a yellow cast, or sprouts appear from the damaged 

 roots . 



Control of pine mice is more difficult and seldom as effective 

 as for meadow mice. The broadcast method of distributing poisoned 

 baits recommended for meadow mice may be only partially success- 

 ful in controlling this species. It should be noted that control 

 of vegetation may not have any effect on pine mice because of 

 their subterranean living habits. 



To obtain good control, orchard mouse baits should be placed 

 in underground trails where the animals spend most of their time. 

 If the infested area is small, hand baiting of the pine mouse 

 natural runways is effective. 



For larger areas, the use of the Trial Builder Machine is 

 an advantage if soil and sod conditions permit. Be sure the machine 

 is aligned properly and is making a good tunnel through the sod. 

 Artificial trails on at least 2 sides of each tree are required for 

 adequate coverage. 



Whether an orchardist hand baits for pine mice or uses a 

 machine, there is one absolute necessity: the artificial trail and 

 the natural runs must be kept as clean as possible . Pine mice 

 maintain clean, well-packed trails. They remove all foreign matter 

 and debris, especially soil, from the tunnel. In the process, mice 

 quite often will cover or carry out the treated bait with other 

 materials . 



NOTE : As in previous years, a permit for bait application must 

 be obtained from the Massachusetts Division of Fisheries and Wild- 

 life, 100 Cambridge Street, Boston, Massachusetts 02202, before any 

 orchard mouse control can be done using toxic baits. 



