From Log to Lumber: Word Relationships at the Sawmill

Inside a Sawmill

1Look around your home, and you will probably find something made of wood, such as a table, a bookshelf, or the frame hidden inside the walls. Much of that wood began as a tree and then took a trip to a sawmill. A sawmill is a factory where logs are cut into boards. The boards are sold as lumber to builders, furniture makers, and stores.

2The trip begins in the log yard. Big trucks stacked high with logs lumber slowly through the gate. A loader with giant claws lifts the logs off each truck and piles them in long rows. At some mills, sprinklers spray the piles with water so the logs do not dry out and crack before they are cut. A worker may log each truckload in a computer, writing down how many logs came in and what kind of trees they came from.

3Next, the logs go to a debarker, a machine that strips away the bark. Bark is the rough outer layer that protects a tree while it grows. Removing it helps keep the saw blades sharp, because bark can carry dirt and tiny stones. Sawmill machines can be so loud that workers wear ear protection. One visitor joked that the debarker sounded like a whole pack of dogs trying to bark at once.

4Then the real cutting begins. In many modern mills, a scanner measures each log so that a computer can plan how to cut the most boards from it. A huge saw slices the log into thick slabs, and smaller saws trim each slab into boards. On a class trip last spring, students from Oak Hill School saw the blade zip through a log in just seconds. Afterward, they ran their fingers along the grain, the pattern of lines that runs through the wood.

5Freshly cut boards hold a lot of water. Woodworkers call this wet wood "green," even though it is not green in color. Before lumber can be used, its moisture content, or the amount of water inside it, must drop. Some mills stack the boards outdoors with thin strips of wood between them so air can flow through. Others dry the boards faster in a large heated room called a kiln. As wood dries, it shrinks a little, and dry boards are less likely to twist or bend later.

6Finally, a machine called a planer shaves the rough surface of each board until it is smooth and flat. At many mills, very little of the log goes to waste. Bark is often ground into mulch for gardens, and sawdust can be pressed into fuel pellets or used as soft bedding for farm animals. A well-run sawmill turns almost nothing into refuse. The next time you sit at a wooden desk, think about the long trip it took from the forest to your classroom.