MAINE AGRICULTURAL EXPERIMENT STATION. 89 



it can be so delicately adjusted that a weight of less than half a 

 pound on the treadle will spring the trap. All bearing surfaces 

 are made of beech because of the well-known property of this 



I 



FIG. 23. Trap nest closed. View from above. 



wood to take on a highly polished surface with wear. The nests 

 in use at the Maine Station have the doors of hard wood, in 

 order to get greater durability. Where trap nests are constantly 

 in use, flimsy construction is not economical in the long run. 

 For temporary use the nest door could be constructed of soft 

 wood. 



The trap nests are not made with covers because they are 

 used in tiers and slide in and out like drawers. They can be 



