Owls are a valuable part of nature, especially as rodent control for vineyards and farms. These birds of prey catch and eat small rodents like mice, rats and rabbits and can keep down populations of unwanted birds as well, such as crows. Owls perform the same function on stable properties, where mice and rats can become a problem. To attract owls to your property, give them a place for housing and nesting in your trees. Owl boxes are ideal for owl nets. Different sizes of boxes will attract different breeds of owls.
Research owl breeds in your area. The box you build should be adequate to house the owls that live in your region. Larger owls (barred owls) take larger boxes, while small owls (screech owls) take small boxes.
Cut your lumber. To build a 14-inch by 14-inch by 28-inch box for large owls, cut two pieces of seven-inch by 14-inch lumber. Lay them side by side as the floor of the owl box. Use scraps from your cuttings to build a frame for the pieces and nail them together. Never allow nails or screws to stick through the wood, as the owls might get cut.
Lay two seven-inch-wide boards side by side, with the bottom edges aligned. These are for your the sides of your owl box. Mark a sloping roof line on the tops of the sides. The roofline should slope up: 30 inches from the bottom at the front to 34 inches from the bottom at the back. Cut along this line, and then erect the sides and hammer them onto the bottom frame.
Cut the front and back for your owl box, sized to what you have constructed so far. If you've followed this pattern, you'll cut both the front and back to seven and three-fourths-inch wide, so that they overlap with the side pieces. Cut the top edges of the front and back at a 30-degree angle to accommodate the roof. Nail on the back, but keep the front of the owl box separate.
Cut the entrance for the owl box into the front. Draw an eight-inch circle in the board, approximately four inches below what will be the roof. Cut out the circle with the jigsaw. Construct an "owlet ladder" for the babies to climb out of the box, using scrap wood. Fasten this to the inside of the front, just below the door. Nail the front to the owl box.
Nail the plywood to the top of your owl box as your roof. Place the roof flush with the back and hanging over the front and sides. Feel free to add roofing decorations like shingles.
Put wood chips on the floor of the owl box, for insulation and nesting material.
Locate your box away from human activity, as many owls will abandon the box and their babies if they experience too much human exposure. If you don't have any luck building your owl box, you can purchase one from an online manufacturer like www.coveside.com.
Be careful with kittens and small dogs when owls are present, as owls will catch and eat anything small enough.