10 



If the roof of a nesting box, made of wood, is horizontal, the 

 water will stand on it, and even if painted it will warp some- 

 what in drying unless covered with zinc, good roof paint, some 

 good roofing felt or other waterproof material. It is well to 

 have a crosspiece nailed (with clinch nails) across the grain on 

 the under side to prevent warping and splitting. If the top 

 slopes downward at an angle of 45° or less and is painted, the 

 water will run off so fast that the roof will not warp much. 



Top, side or front of the box may be hinged to open 

 as a door, or fixed to fasten by means of nails, easily re- 

 moved, slid loosely into sockets arranged for them. White pine 

 from ^ to I of an inch thick is the best lumber. Cedar and cy- 

 press are durable. Grocery or drygoods boxes may be used. The 

 following dimensions will do for flat-roofed dwellings for the 

 birds named. These dimensions are not absolute, but are such 

 as seem to be popular with the birds. The boxes may be made 

 larger if desired, but not very much smaller. The size of the 

 entrance, however, should not be changed. If the roof is not level 

 but slopes forward the back may be two or three inches higher. 

 House Wren. — Interior dimensions, 6 by 

 3| by 3| inches. Entrance hole, f inch in 

 diameter. The long axis may be either 

 horizontal or vertical and the entrance hole 

 near the top. A miniature bird house (Fig. 

 11) will do as well, but takes more time to 



Fig. 11. -Wren house. ^^^^ 



White-breasted Nuthatch. — A box actually occupied by this 

 bird on the grounds of the Rev. William R. Lord, at Dover in 

 1914, measured 5 by 5 inches (inside dimensions). Height, 12 

 inches front; 13| inches back. Long axis, vertical. Entrance 

 front, near top, 1| inches in diameter (Fig. 12). Probably a 

 box made of bark, or slabs with bark on, would attract this 

 bird. 



Red-breasted Nuthatch. — This bird has nested in a No. 2 

 Berlepsch nesting box made of yellow birch by the Meriden 

 Bird House Company, Meriden, New Hampshire, and placed in 

 a gray birch tree, in rather open land, with the entrance slightly 

 more than 7 feet above the ground. The entrance hole is 1| 

 inches in diameter. 



