it must be free from knot holes and cracks, as you want an air-tight hutch if possible, one that the wind won't blow through.
The lumber to be used in making doors and frames should preferably be cypress, as it will not split when a nail is driven into it. In this way they can be made strong and serviceable and will be more apt to withstand the attacks of enemies than that made of flimsy lumber full of splits and cracks.
A good grade of pine ship-lap will do nicely for the hutches and floors, although some people seem to prefer to use flooring. There is no need to do this unless you have a pocket full of money to spend, as flooring is about three or four times as expensive as the ordinary ship-lap would be.
If you have to use the cheaper grade of lumber, or old lumber that is cracked and full of knot holes, it can be covered with tar paper or rubberoid and the draughts and other disadvantages eliminated in this way. A good thing to do, if you want to make the sides of
