PROVIDE NESTING BOXES 35 
Twigs of our wild haws and plums will answer this 
purpose. They should be securely nailed, screwed, 
or otherwise fastened so as to protect the entrance 
holes against cats, crows, squirrels, jays, and shrikes. 
It would pay to find by experiment how our titmice, 
bluebirds, wrens, and nuthatches take to boxes thus 
protected. 
A pair of house wrens nested for several years in a 
box which I had nailed to a thin, peeled pole, about 12 
feet from the ground and placed near young trees 
about 20 feet high. The pole was too thin and too 
smooth for the cats. 
Another good way to protect the boxes from cats is 
to surround the tree about 5 feet from the ground, or 
just below the branches, with several coils of some kind 
of barbed wire about 2 feet wide. The closer the 
barbs are placed, the more effective is the protection. 
Take two narrow pieces of board or lath, tack them, 
one above the other, to the tree by their upper ends ; 
then nail the end of the barbed wire to the tree with 
a steeple tack. Wind the wire around the tree and 
boards as shown in the figure, and fasten the lower 
end of the wire to the last coils. Next fasten the 
barbed wire coil to the lower branches by means of 
a smooth wire, then draw the nail holding the laths 
and pull out the laths. In this way we procure 
elastic barb wire coils, which may remain on the 
tree for a number of years without hindering its ~ 
growth. 
The entrance holes should be turned away from the 
